{"id":23348,"date":"2026-11-03T04:52:26","date_gmt":"2026-11-03T04:52:26","guid":{"rendered":"https:\/\/tradefoxapps.sitepreview.me\/?p=23348"},"modified":"2026-11-06T16:44:32","modified_gmt":"2026-11-06T16:44:32","slug":"s-trap-vs-p-trap","status":"publish","type":"post","link":"https:\/\/tradefoxapps.sitepreview.me\/fr\/s-trap-vs-p-trap\/","title":{"rendered":"S Trap vs P Trap: Outlet Direction, Water Seals and UK Plumbing Rules"},"content":{"rendered":"<div data-elementor-type=\"wp-post\" data-elementor-id=\"23348\" class=\"elementor elementor-23348\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-bd69d62 e-flex e-con-boxed e-con e-parent\" data-id=\"bd69d62\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-cfb4151 elementor-widget elementor-widget-text-editor\" data-id=\"cfb4151\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Ask any plumber the S trap vs P trap question and the honest answer starts with the outlet. On a P trap, waste leaves sideways into the branch pipe. On an S trap, it drops straight down into a vertical connection. That one detail decides where each shape fits on the wall or under the floor.<\/span><\/p><p><span style=\"font-weight: 400;\">What it does not decide is whether the finished job holds its water seal or passes building control. Both shapes are stocked by every major UK manufacturer, in a range of seal depths and connection sizes. Picking the right one is less about the letter S or P and more about the appliance, the pipe run and the ventilation behind it.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-f299ff1 e-flex e-con-boxed e-con e-parent\" data-id=\"f299ff1\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-7e47bbf elementor-widget elementor-widget-heading\" data-id=\"7e47bbf\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The Core Difference: Where the Outlet Points\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a42c1b7 elementor-widget elementor-widget-text-editor\" data-id=\"a42c1b7\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Think of the names as a quick sketch of the trap seen from the side. On a P trap, the water sits in the bend and the outlet runs out horizontally. On an S trap, the same bend holds the seal and the outlet carries on downward. Adjustable traps give you some room to move, as long as you stay inside the maker&#8217;s instructions. <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-89b5a94 elementor-widget elementor-widget-html\" data-id=\"89b5a94\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<style>\n  .trap-table {\n    font-family: 'Inter', Arial, sans-serif;\n    font-size: 16px;\n    border-collapse: collapse;\n    color: #000;\n  }\n  .trap-table th,\n  .trap-table td {\n    text-align: left;\n    padding: 10px 16px 10px 16px;\n    vertical-align: top;\n  }\n  .trap-table th {\n    font-weight: 600;\n    text-align: center;\n    background: #f7f7f7;\n  }\n  \n<\/style>\n\n<table class=\"trap-table\">\n  <thead>\n    <tr>\n      <th>Fonctionnalit\u00e9<\/th>\n      <th>P Trap<\/th>\n      <th>S Trap<\/th>\n    <\/tr>\n  <\/thead>\n  <tbody>\n    <tr>\n      <td>Outlet direction<\/td>\n      <td>Sideways from the bend<\/td>\n      <td>Downwards from the bend<\/td>\n    <\/tr>\n    <tr>\n      <td>Usual connection<\/td>\n      <td>Branch running out to the <br>wall<\/td>\n      <td>Waste dropping below the appliance<\/td>\n    <\/tr>\n    <tr>\n      <td>Water seal<\/td>\n      <td>Held in the bend<\/td>\n      <td>Held in the bend<\/td>\n    <\/tr>\n    <tr>\n      <td>Seal depth<\/td>\n      <td>Set by the product you fit<\/td>\n      <td>Set by the product you fit<\/td>\n    <\/tr>\n    <tr>\n      <td>Siphon risk<\/td>\n      <td>Lower in most layouts<\/td>\n      <td>Higher if the drop runs full and <br>unvented<\/td>\n    <\/tr>\n  <\/tbody>\n<\/table>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f5ff9b7 elementor-widget elementor-widget-heading\" data-id=\"f5ff9b7\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Does a P Trap Always Connect Through a Wall?\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-535f6b2 elementor-widget elementor-widget-text-editor\" data-id=\"535f6b2\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Not always. P traps often serve a branch heading to the wall, and S traps often drop below the basin or bath, but those are habits, not rules. Follow the whole waste route before you decide. The way the pipe leaves the trap does not tell you where it finally meets the stack or drain.<\/span><\/p><p><span style=\"font-weight: 400;\">One more thing on the horizontal outlet: it is not an excuse to lay the branch dead level. The pipe still needs the fall that suits its diameter and load, or it will either hold water or pull the seal. <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-434ea8c e-flex e-con-boxed e-con e-parent\" data-id=\"434ea8c\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-66cc21d elementor-widget elementor-widget-heading\" data-id=\"66cc21d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">How a Trap Holds Its Water Seal\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8527952 elementor-widget elementor-widget-text-editor\" data-id=\"8527952\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">The bend keeps a plug of water after every discharge. That plug is the barrier that stops foul air from the drain coming back up through the appliance. Simple idea, and the whole reason you fit a trap at all.<\/span><\/p><p><span style=\"font-weight: 400;\">The catch is that the seal has to survive real use, including other appliances firing on the same system. Traps can sit full of water on the bench and still lose part of the seal once pressure swings hit them. And seal depth is a fixed figure for the product. It is not the height of the trap body, the pipe size or the gap under the appliance.\u00a0 <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-7d6e783 e-flex e-con-boxed e-con e-parent\" data-id=\"7d6e783\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-b095673 elementor-widget elementor-widget-heading\" data-id=\"b095673\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Minimum Trap Sizes and Seal Depths in England\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-9a57ac4 elementor-widget elementor-widget-text-editor\" data-id=\"9a57ac4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">These are the baseline figures from Table 1 of England&#8217;s<\/span><strong><a href=\"https:\/\/assets.publishing.service.gov.uk\/media\/5a80cf9ded915d74e33fc8ae\/BR_PDF_AD_H_2015.pdf\"> Approved Document H<\/a><\/strong><span style=\"font-weight: 400;\">.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-14a8208 elementor-widget elementor-widget-html\" data-id=\"14a8208\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<style>\n  .trap-size-table {\n    font-family: 'Inter', Arial, sans-serif;\n    font-size: 16px;\n    border-collapse: collapse;\n    color: #000;\n    \n  }\n  .trap-size-table th,\n  .trap-size-table td {\n    text-align: left;\n    padding: 12px 20px 12px 20;\n    vertical-align: top;\n  }\n  .trap-size-table th {\n    font-weight: 600;\n    text-align: center;\n    background: #f7f7f7;\n  }\n \n<\/style>\n\n<table class=\"trap-size-table\">\n  <thead>\n    <tr>\n      <th>Appliance<\/th>\n      <th>Minimum Trap Diameter<\/th>\n      <th>Minimum Water Seal Depth<\/th>\n    <\/tr>\n  <\/thead>\n  <tbody>\n    <tr>\n      <td>Washbasin<\/td>\n      <td>32 mm<\/td>\n      <td>75 mm<\/td>\n    <\/tr>\n    <tr>\n      <td>Sink<\/td>\n      <td>40 mm<\/td>\n      <td>75 mm<\/td>\n    <\/tr>\n    <tr>\n      <td>Bath<\/td>\n      <td>40 mm<\/td>\n      <td>50 mm<\/td>\n    <\/tr>\n    <tr>\n      <td>Shower<\/td>\n      <td>40 mm<\/td>\n      <td>50 mm<\/td>\n    <\/tr>\n  <\/tbody>\n<\/table>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-555ca18 elementor-widget elementor-widget-text-editor\" data-id=\"555ca18\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Several concessions apply alongside the table. Where a bath, shower or sink discharges straight into a gully, the seal can drop to 38 mm. Spray-tap basins with a flush-grated waste are also allowed a shallower seal, since they never take a plug or a full slug of water.<\/span><\/p><p><span style=\"font-weight: 400;\">There is a separate figure people often mix up. Approved Document H asks every trap to keep at least 25 mm of seal under working and test conditions. That is the minimum left after pressure swings, not a licence to fit a 25 mm trap in place of a 50 mm or 75 mm one. Read the table and its footnotes together, or you will talk yourself into a trap that is too shallow. <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-8d44b63 e-flex e-con-boxed e-con e-parent\" data-id=\"8d44b63\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-e7f1e92 elementor-widget elementor-widget-heading\" data-id=\"e7f1e92\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Why the Figures Change Across the UK\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-70886cc elementor-widget elementor-widget-text-editor\" data-id=\"70886cc\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Here is where plenty of online advice goes wrong. The England numbers are not UK numbers.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-93c3f1c elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"93c3f1c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Northern Ireland: <\/b><a href=\"https:\/\/www.finance-ni.gov.uk\/publications\/technical-booklet-n\"><b> Technical Booklet N <\/b><\/a>sets a deeper 75 mm seal for baths and showers, not the 50 mm England allows. It only lets that fall to 40 mm for a ground-floor appliance discharging into an external gully.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>\u2060Scotland: <\/b>The building standards point to BS EN 12056-2 for sanitary pipework under <a href=\"https:\/\/www.gov.scot\/publications\/building-standards-technical-handbook-2022-domestic\/3-environment\/3-7-wastewater-drainage\/\" target=\"_blank\" rel=\"noopener\"><b> Standard 3.7<\/b><\/a>, rather than a single national seal-depth table.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>\u2060Wales: <\/b>Le<a href=\"https:\/\/www.gov.wales\/approved-document-h-drainage-and-waste-disposal\" target=\"_blank\" rel=\"noopener\"><b> Welsh Approved Document H <\/b><\/a>keeps its own guidance and ties seal protection to the design of the branch discharge pipes.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f2e2a50 elementor-widget elementor-widget-html\" data-id=\"f2e2a50\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<style>\n  .guidance-table {\n    font-family: 'Inter', Arial, sans-serif;\n    font-size: 16px;\n    border-collapse: collapse;\n    color: #000;\n  }\n  .guidance-table th,\n  .guidance-table td {\n    text-align: left;\n    padding: 12px 16px 12px 16;\n    vertical-align: top;\n  }\n  .guidance-table th {\n    font-weight: 600;\n    text-align: center;\n    background: #f7f7f7;\n  }\n\n<\/style>\n\n<table class=\"guidance-table\">\n  <thead>\n    <tr>\n      <th>Nation<\/th>\n      <th>Guidance To Check<\/th>\n    <\/tr>\n  <\/thead>\n  <tbody>\n    <tr>\n      <td>England<\/td>\n      <td>Approved Document H: Drainage and Waste Disposal<\/td>\n    <\/tr>\n    <tr>\n      <td>Wales<\/td>\n      <td>Welsh Approved Document H: Drainage and Waste Disposal<\/td>\n    <\/tr>\n    <tr>\n      <td>Scotland<\/td>\n      <td>Building Standards Technical Handbook, Standard 3.7<\/td>\n    <\/tr>\n    <tr>\n      <td>Northern Ireland<\/td>\n      <td>Technical Booklet N: Drainage<\/td>\n    <\/tr>\n  <\/tbody>\n<\/table>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f78a4a1 elementor-widget elementor-widget-text-editor\" data-id=\"f78a4a1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Always check the edition and any amendments that apply to the job. Advice built on an overseas plumbing code is not a UK rule, and it causes more argument on site than almost anything else.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-f9e0b2f e-con-full e-flex e-con e-parent\" data-id=\"f9e0b2f\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-4e4f04e elementor-invisible elementor-widget elementor-widget-image\" data-id=\"4e4f04e\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;_animation&quot;:&quot;fadeInUp&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"825\" height=\"550\" src=\"https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/What-Causes-Trap-Seal-Loss.png\" class=\"attachment-large size-large wp-image-23350\" alt=\"What Causes Trap Seal Loss\" srcset=\"https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/What-Causes-Trap-Seal-Loss.png 825w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/What-Causes-Trap-Seal-Loss-300x200.png 300w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/What-Causes-Trap-Seal-Loss-768x512.png 768w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/What-Causes-Trap-Seal-Loss-18x12.png 18w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/What-Causes-Trap-Seal-Loss-600x400.png 600w\" sizes=\"(max-width: 825px) 100vw, 825px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-6fd6cc5 e-flex e-con-boxed e-con e-parent\" data-id=\"6fd6cc5\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-c65f8e7 elementor-widget elementor-widget-heading\" data-id=\"c65f8e7\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">What Causes Trap Seal Loss?\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3f39b80 elementor-widget elementor-widget-text-editor\" data-id=\"3f39b80\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Blaming the outlet shape is the lazy diagnosis. Seal loss usually traces back to one of these:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8be59fc elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"8be59fc\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Self-Siphonage: <\/b>The appliance's own discharge drags water out of its trap. This is the real reason S traps earned their reputation, since a full vertical drop can start siphoning.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Induced Siphonage:<\/b> A discharge elsewhere on the system drops the pressure and pulls on a neighbouring trap.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Positive Pressure: <\/b>Pressure building in the stack pushes back and, if it is strong enough, blows air through the seal.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Evaporation: <\/b>An appliance left unused slowly loses its water to the air.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Leakage: <\/b>A crack or a weeping joint in the bend lets the standing water drain away.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2913a9b elementor-widget elementor-widget-text-editor\" data-id=\"2913a9b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Faults above the waterline can leak during a discharge without ever emptying the standing seal, so where the defect lies matters as much as what it is. Good branch design and ventilation are what hold the seal steady against these swings. Saying every S trap siphons, or that a P trap never does, is simply wrong. <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-5145405 e-flex e-con-boxed e-con e-parent\" data-id=\"5145405\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-49a2fdc elementor-widget elementor-widget-heading\" data-id=\"49a2fdc\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Are S Traps Banned in the UK?\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4542828 elementor-widget elementor-widget-text-editor\" data-id=\"4542828\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">No. That claim gets repeated a lot, and it is not true. UK manufacturers list S traps next to P traps for jobs that suit them.<\/span><\/p><p><span style=\"font-weight: 400;\">Being on sale is not the same as being compliant in your particular layout, mind you. The trap still has to match the appliance, the required seal depth and the system it joins. An S trap on a short, unvented vertical drop is asking for self-siphonage, and that is a design problem rather than a ban.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-15635d5 e-flex e-con-boxed e-con e-parent\" data-id=\"15635d5\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-e6cc434 elementor-widget elementor-widget-heading\" data-id=\"e6cc434\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">S Trap vs P Trap: Choosing for the Appliance\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3fcbf8d elementor-widget elementor-widget-text-editor\" data-id=\"3fcbf8d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">This is where the S trap vs P trap choice gets made properly, appliance by appliance.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3ad8394 elementor-widget elementor-widget-heading\" data-id=\"3ad8394\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Washbasins and Kitchen Sinks\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5f2f3e7 elementor-widget elementor-widget-text-editor\" data-id=\"5f2f3e7\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Start with the appliance waste, the seal depth you need and the branch route you have. P traps suit a connection heading back to the wall. S traps suit a drop straight down below the unit. Check the real dimensions, the joint type and the pipe sizes before you commit to either.<\/span><\/p><p><span style=\"font-weight: 400;\">Where a sink trap also takes a washing machine or dishwasher, treat those connections as part of the design, and cap any spare inlet as the maker specifies. Cabinet space can steer how you route things, but it never overrides the seal the trap has to keep.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-78aa7ba elementor-widget elementor-widget-heading\" data-id=\"78aa7ba\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Baths and Showers\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f55daaf elementor-widget elementor-widget-text-editor\" data-id=\"f55daaf\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Tight clearance under a tray or a bath is the usual headache, so sort the trap, the appliance and the surrounding build together, early. Run through:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-55e16b8 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"55e16b8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Seal Depth: <\/b>Confirm the trap meets the figure for your nation, 50 mm in England, 75 mm in Northern Ireland.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Flow: <\/b>Match the trap to the appliance and the water it will actually shift.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Outlet Route: <\/b>Leave a clean path for the waste pipe at the right fall.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Access: <\/b>Keep the cleaning or removal method reachable once tiling and panels go in.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c70ca8d elementor-widget elementor-widget-text-editor\" data-id=\"c70ca8d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Low-profile traps are fine only where their approved use and install conditions are met. Clearance on its own is not a reason to fit one. And never stack two traps in series to make up a seal depth, since that traps air between them and kills the flow.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c4a97c8 elementor-widget elementor-widget-heading\" data-id=\"c4a97c8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">WC Pans\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6b98432 elementor-widget elementor-widget-text-editor\" data-id=\"6b98432\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">The WC is a different animal. The pan has its own built-in seal, so an S-outlet or P-outlet pan is describing which way the pan discharges, not a separate trap under a basin. Specify the pan, the connector and the drain connection as one matched set, and leave basin-trap logic out of it. <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-8cfa014 e-flex e-con-boxed e-con e-parent\" data-id=\"8cfa014\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-ca39a01 elementor-widget elementor-widget-heading\" data-id=\"ca39a01\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Anti-Siphon Traps and Air Admittance Valves\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ea7422e elementor-widget elementor-widget-text-editor\" data-id=\"ea7422e\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">These parts deal with negative pressure, and each has a clear limit worth knowing.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d6e74a8 elementor-widget elementor-widget-heading\" data-id=\"d6e74a8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Valved Anti-Siphon Traps\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-930b39b elementor-widget elementor-widget-text-editor\" data-id=\"930b39b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Valved anti-siphon traps let air in when the pressure drops, then close once the surge passes. That protects the seal without a separate vent pipe. It will not fix undersized pipework or a leaking joint, so fit it for what it does and solve the rest on its own.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2deed31 elementor-widget elementor-widget-heading\" data-id=\"2deed31\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Air Admittance Valves\n<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d74d7db elementor-widget elementor-widget-text-editor\" data-id=\"d74d7db\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">An <a href=\"https:\/\/tradefoxapps.sitepreview.me\/fr\/air-admittance-valve\/\">air admittance valve<\/a>, or AAV, works on the same one-way idea. It opens to admit air under negative pressure and shuts against positive pressure. Because it only ever lets air in, it cannot relieve positive pressure from the system, and it never replaces proper stack ventilation.<\/span><\/p><p><span style=\"font-weight: 400;\">UK valves should meet BS EN 12380, and Approved Document H expects them to keep the below-ground ventilation the drain still relies on. Follow the maker&#8217;s rules on position, the right way up, air supply and access for servicing.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-f30c1d9 e-con-full e-flex e-con e-parent\" data-id=\"f30c1d9\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-bf6946f elementor-invisible elementor-widget elementor-widget-image\" data-id=\"bf6946f\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;_animation&quot;:&quot;fadeInUp&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"825\" height=\"550\" src=\"https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/The-Pipework-Decides-Performance-Too.png\" class=\"attachment-large size-large wp-image-23351\" alt=\"The Pipework Decides Performance Too\" srcset=\"https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/The-Pipework-Decides-Performance-Too.png 825w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/The-Pipework-Decides-Performance-Too-300x200.png 300w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/The-Pipework-Decides-Performance-Too-768x512.png 768w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/The-Pipework-Decides-Performance-Too-18x12.png 18w, https:\/\/tradefoxapps.sitepreview.me\/wp-content\/uploads\/2026\/11\/The-Pipework-Decides-Performance-Too-600x400.png 600w\" sizes=\"(max-width: 825px) 100vw, 825px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-b0786fd e-flex e-con-boxed e-con e-parent\" data-id=\"b0786fd\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-249b9f1 elementor-widget elementor-widget-heading\" data-id=\"249b9f1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The Pipework Decides Performance Too\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-808b5cf elementor-widget elementor-widget-text-editor\" data-id=\"808b5cf\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Even a sound trap fails on bad pipework. Give the branch the same attention as the fitting:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-43937e6 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"43937e6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Capacity: <\/b>Size the branch for the appliances feeding it.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Length and Fall: <\/b>Use the limit for your layout, not one blanket figure.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Direction Changes: <\/b>Use swept fittings and keep the route sensible.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Joints: <\/b>Check that the pipe material and connection system match.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Support: <\/b>Hold the pipe without loading the trap or appliance.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Ventilation: <\/b>Plan for pressure control across the whole run.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Access: <\/b>Leave a real way to rod or remove parts later.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6900f13 elementor-widget elementor-widget-text-editor\" data-id=\"6900f13\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">BS EN 12056-2 covers the layout and sizing of gravity sanitary pipework, and BS EN 274-1 sets the requirements for the waste fittings themselves. Product and system rules work together, but one does not stand in for the other. <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-41b7378 e-flex e-con-boxed e-con e-parent\" data-id=\"41b7378\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-d8ee708 elementor-widget elementor-widget-heading\" data-id=\"d8ee708\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Diagnosing Gurgles, Smells and Slow Drainage\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-59d2ac9 elementor-widget elementor-widget-text-editor\" data-id=\"59d2ac9\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\"><a href=\"https:\/\/tradefoxapps.sitepreview.me\/fr\/toilet-gurgling\/\">Gurgling<\/a> after another appliance drains points to pressure moving through the system. It does not name the faulty part on its own. <a href=\"https:\/\/tradefoxapps.sitepreview.me\/fr\/smelly-drains-in-bathroom\/\">Smells<\/a> can come from a dried-out seal, a cracked trap, a bad joint or a fault further down the drain.<\/span><\/p><p><span style=\"font-weight: 400;\">Swapping an S trap for a P trap before you know the cause often leaves the problem exactly where it was. Work out which layer is failing first:<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2f76392 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-widget elementor-widget-icon-list\" data-id=\"2f76392\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"icon-list.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-icon-list-items\">\n\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Local: <\/b>Damage, a leak, a blockage or a poor appliance connection.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>Branch:<\/b> Wrong size, wrong route or no allowance for pressure change.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-long-arrow-alt-right\" viewbox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M313.941 216H12c-6.627 0-12 5.373-12 12v56c0 6.627 5.373 12 12 12h301.941v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.569 0-33.941l-86.059-86.059c-15.119-15.119-40.971-4.411-40.971 16.971V216z\"><\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text\"><b>System: <\/b>Shared stacks, ventilation or something downstream.<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c20df07 elementor-widget elementor-widget-text-editor\" data-id=\"c20df07\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Before you open old <a href=\"https:\/\/tradefoxapps.sitepreview.me\/fr\/waste-pipe-sizes\/\">waste pipework<\/a>, treat the contents as a health risk and glove up. The<\/span><strong><a href=\"https:\/\/www.hse.gov.uk\/pubns\/indg198.pdf\"> HSE sets out the health hazards of working with sewage<\/a><\/strong><span style=\"font-weight: 400;\">, and plumbers sit on its list of exposed workers.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-547c52e e-flex e-con-boxed e-con e-parent\" data-id=\"547c52e\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-0eaa3ec elementor-widget elementor-widget-heading\" data-id=\"0eaa3ec\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Testing and Handover\n<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-330949f elementor-widget elementor-widget-text-editor\" data-id=\"330949f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Check connections while the appliance discharges, and watch how the system behaves when more than one outlet runs at once. The aim is simple: every appliance drains cleanly, and nothing pulls another trap&#8217;s seal while it does.<\/span><\/p><p><span style=\"font-weight: 400;\">No visible drip does not prove the joints are airtight, so keep the discharge checks and the specified air test as two separate things. Record the trap and ventilation parts you fitted, and confirm the access still works once the room is finished.<\/span><\/p><p><span style=\"font-weight: 400;\">On S trap vs P trap, the right call is the fitting that suits the outlet route while meeting the appliance, seal, ventilation, and access needs of the whole drainage design. Get those right, and the letter on the box barely matters.<\/span><\/p><p><span style=\"font-weight: 400;\">A trap needs to work with the pipework around it. Build your plumbing knowledge with <\/span><strong><a href=\"https:\/\/learn.tradefoxapp.com\/\">Tradefox\u2019s<\/a><\/strong><span style=\"font-weight: 400;\"> interactive courses, using guided simulations and feedback to support your learning. Get started and work through lessons at your own pace. <\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>","protected":false},"excerpt":{"rendered":"<p>Ask any plumber the S trap vs P trap question and the honest answer starts with the outlet. On a P trap, waste leaves sideways into the branch pipe. On an S trap, it drops straight down into a vertical connection. That one detail decides where each shape fits on the wall or under the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":23349,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"no-sidebar","site-content-layout":"","ast-site-content-layout":"full-width-container","site-content-style":"unboxed","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center 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center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"_glsr_average":0,"_glsr_ranking":0,"_glsr_reviews":0,"footnotes":""},"categories":[27],"tags":[1822,2802,2055,2798,2264,2056,2806,2797,2804,2799,2800,2059,2805,1485,2801,1490,1074,2803,156,2032],"class_list":["post-23348","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-plumbing","tag-branch-pipe","tag-induced-siphonage","tag-negative-pressure","tag-p-trap","tag-pipe-sizes","tag-positive-pressure","tag-pressure-control","tag-s-trap","tag-sanitary-pipework","tag-seal-depth","tag-sink-trap","tag-slow-drainage","tag-stack-ventilation","tag-trap-seal","tag-trap-sizes","tag-vent-pipe","tag-washing-machine","tag-waste-fittings","tag-waste-pipe","tag-water-seal"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.8 - 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