{"id":832,"date":"2019-04-26T14:47:42","date_gmt":"2019-04-26T14:47:42","guid":{"rendered":"https:\/\/www.bcta.group\/attma\/?page_id=832"},"modified":"2025-01-16T12:52:01","modified_gmt":"2025-01-16T12:52:01","slug":"fan-capacity-calculator","status":"publish","type":"page","link":"https:\/\/www.bcta.group\/attma\/fan-capacity-calculator\/","title":{"rendered":"Fan Capacity Calculator"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"832\" class=\"elementor elementor-832\" data-elementor-settings=\"{&quot;ha_cmc_init_switcher&quot;:&quot;no&quot;}\" data-elementor-post-type=\"page\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-5fd763d elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"5fd763d\" data-element_type=\"section\" data-e-type=\"section\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-ba6cba7\" data-id=\"ba6cba7\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-02146c7 elementor-widget elementor-widget-heading\" data-id=\"02146c7\" 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\">Fan Capacity Calculator<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-64a7dc1a elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"64a7dc1a\" data-element_type=\"section\" data-e-type=\"section\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-5e7c383c\" data-id=\"5e7c383c\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-1847a88f elementor-widget elementor-widget-text-editor\" data-id=\"1847a88f\" 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><\/p>\n<p>The ATTMA Trade Association has developed a Blower Door Fan Capacity Calculator to help ATTMA members calculate how many fans are required for Level 2 buildings.<\/p>\n<p><\/p>\n<p><\/p>\n<p>The fan capacity calculator works on the basis of some assumptions such as a quality power supply and running into a free air unobstructed route. \u00a0The fans that can be used are: Infiltec, Retrotec (1000, 2000, 3000, 5000 and 6000 series) and The Energy Conservatory (Model 3, Model 4 and Ductblasters).<\/p>\n<p><\/p>\n<p><\/p>\n<p>The tool requires the blower door fan, the target air permeability and the size of the building (surface area) to be identified. The calculator will provide you a reasonable estimate for the number of fans that will be needed.<\/p>\n<p><\/p>\n<p><\/p>\n<p>Please note, as per the <a href=\"https:\/\/www.bcta.group\/product\/test-standards\">ATTMA guidance<\/a>, you should always take approximately 20% more fan power than required to allow for a higher result. It is not uncommon for the target to be changed post test. Taking an extra 20% fan power will allow the result to still be valid and used for compliance.<\/p>\n<p><\/p>\n<p><\/p>\n<p>Tests must always meet 50Pa Induced Pressure to be valid.<\/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-ed14c17 elementor-widget elementor-widget-shortcode\" data-id=\"ed14c17\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"shortcode.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-shortcode\"><p>The following tool was provided to ATTMA by Stroma Technology Ltd.<\/p>\r\n<!-- Content starts here -->\r\n<script type=\"text\/javascript\">\r\nvar f_make = new Array()\r\nf_make[0] = \"-- Select an Option --\";\r\nf_make[1] = \"Energy Conservatory\";\r\nf_make[2] = \"Infiltec\";\r\nf_make[3] = \"Retrotec\";\r\nvar f_model = [\r\n  {m_make: 1, m_text: \"Duct Blaster\", m_flow: 0.64},\r\n  {m_make: 1, m_text: \"Model 3\", m_flow: 2.10},\r\n  {m_make: 1, m_text: \"Model 4\", m_flow: 2.17},\r\n  {m_make: 2, m_text: \"E3\", m_flow: 2.57},\r\n  {m_make: 3, m_text: \"200 series\", m_flow: 0.28},\r\n  {m_make: 3, m_text: \"300 series\", m_flow: 0.37},\r\n  {m_make: 3, m_text: \"1000 series\", m_flow: 2.64},\r\n  {m_make: 3, m_text: \"2000 series\", m_flow: 2.64},\r\n  {m_make: 3, m_text: \"3000 series\", m_flow: 3.78},\r\n  {m_make: 3, m_text: \"5000 series\", m_flow: 2.28},\r\n  {m_make: 3, m_text: \"6000 series\", m_flow: 3.09}\r\n];\r\nfunction pop_make(){\r\n  var e = document.fan_calc.fan_make;\r\n  for (i=0; i<f_make.length; i++){\r\n    e.options[i] = new Option(f_make[i], i);\r\n  }\r\n}\r\nfunction pop_model(){\r\n  document.fan_calc.result.value=\"\";\r\n  var sel = document.fan_calc.fan_make[document.fan_calc.fan_make.selectedIndex].value;\r\n  var e = document.fan_calc.fan_model;\r\n  e.options.length=1;\r\n  for (i=0; i<f_model.length; i++){\r\n    if(f_model[i].m_make == sel){\r\n      e.options[e.options.length] = new Option(f_model[i].m_text, f_model[i].m_flow);\r\n    }\r\n  }\r\n}\r\nfunction is_blank(s){\r\n  for(var i=0; i < s.length; i++){var c = s.charAt(i); if((c != ' ') && (c != '\\n') && (c != '\\t')) return false;} return true; } \r\n  function fan_no(){\r\n   var fans = 0;\r\n   var flow = document.fan_calc.fan_model[document.fan_calc.fan_model.selectedIndex].value * 3600;\r\n   var air_perm = document.fan_calc.air_permeability.value;\r\n   var env = document.fan_calc.envelope.value;\r\n   var fan_eq = env * air_perm \/ flow;\r\n   var fan_round = Math.round(fan_eq*1000)\/1000;\r\n   var fan_ceil = Math.ceil(fan_eq);\r\n   var er = \"\";\r\n   var er1 = \"\";\r\n   var er2 = \"\";\r\n   if(isNaN(air_perm)){er1 += \"\\n     - contain only numbers\";}\r\n   if(air_perm > 10){er1 += \"\\n     - not be greater than 10\";}\r\n   if(is_blank(air_perm)){er1 += \"\\n     - not be left blank\";}\r\n   if(isNaN(env)){er2 += \"\\n     - contain only numbers\";}\r\n   if(is_blank(env)){er2 += \"\\n     - not be left blank\";}\r\n   if(er1.length > 0 || er2.length > 0){\r\n    er += \"Please correct the following errors \\n___________________________________\\n\";\r\n    if(er1.length > 0){er += \"\\nThe air permeability must:\" + er1;}\r\n    if(er2.length > 0){er += \"\\nThe building envelope must:\" + er2;}\r\n    alert(er);\r\n    document.fan_calc.result.value = \"!!!ERROR!!!\";\r\n  }\r\n  else{\r\n    fans = fan_round + \" (\" + fan_ceil + \" Fan\";\r\n    if(fan_ceil > 1){fans += \"s\";}\r\n    fans += \")\";\r\n    document.fan_calc.result.value = fans;\r\n  }\r\n}\r\n<\/script>\r\n<form name=\"fan_calc\">\r\n<table>\r\n<tbody>\r\n<tr>\r\n<th>Make<\/th>\r\n<th>Model<\/th>\r\n<th>Air Permeability<br \/>\r\n(m\u00b3\/h.m\u00b2 @ 50Pa)<\/th>\r\n<th>Building<br \/>\r\nEnvelope (m\u00b2)<\/th>\r\n<th>No. of Fans<\/th>\r\n<\/tr>\r\n<tr>\r\n<td align=\"left\" valign=\"top\"><select name=\"fan_make\" onchange=\"pop_model()\"><option value=\"0\">Select an Option<\/option><\/select><\/td>\r\n<td align=\"left\" valign=\"top\"><select name=\"fan_model\" onchange=\"fan_no()\"><option value=\"0\">Select an Option<\/option><\/select><\/td>\r\n<td align=\"left\" valign=\"top\"><input name=\"air_permeability\" size=\"4\" type=\"text\" value=\"10\" \/><\/td>\r\n<td align=\"left\" valign=\"top\"><input name=\"envelope\" size=\"5\" type=\"text\" value=\"300\" \/><\/td>\r\n<td align=\"left\" valign=\"top\"><input name=\"result\" size=\"18\" type=\"text\" \/><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<p><input style=\"font-size: 12px;\" type=\"button\" value=\"Calculate\" onclick=\"fan_no();\" \/><\/p>\r\n<\/form>\r\n<p>This tool should only be used for guidance and is based on the 240v 50hz equipment specifications from new. ATTMA take no responsibility for errors.\r\n\t<script type=\"text\/javascript\">pop_make()<\/script><\/p><\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Fan Capacity Calculator The ATTMA Trade Association has developed a Blower Door Fan Capacity Calculator to help ATTMA members calculate<\/p>\n","protected":false},"author":3,"featured_media":834,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"elementor_header_footer","meta":{"footnotes":""},"class_list":["post-832","page","type-page","status-publish","has-post-thumbnail","hentry"],"publishpress_future_action":{"enabled":false,"date":"2026-04-17 23:42:39","action":"change-status","newStatus":"draft","terms":[],"taxonomy":"","extraData":[]},"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/pages\/832","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/comments?post=832"}],"version-history":[{"count":19,"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/pages\/832\/revisions"}],"predecessor-version":[{"id":5174,"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/pages\/832\/revisions\/5174"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/media\/834"}],"wp:attachment":[{"href":"https:\/\/www.bcta.group\/attma\/wp-json\/wp\/v2\/media?parent=832"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}