{"id":136,"date":"2026-10-02T19:01:19","date_gmt":"2026-10-02T19:01:19","guid":{"rendered":"https:\/\/irantopdown.com\/en\/?page_id=136"},"modified":"2026-10-02T21:32:53","modified_gmt":"2026-10-02T21:32:53","slug":"top-down-method","status":"publish","type":"page","link":"https:\/\/irantopdown.com\/en\/top-down-method\/","title":{"rendered":"Top-Down Method"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"136\" class=\"elementor elementor-136\" data-elementor-post-type=\"page\">\n\t\t\t\t<section class=\"elementor-element elementor-element-295616a e-con-boxed itd-page-hero e-flex e-con e-parent\" data-id=\"295616a\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-af73bda e-con-full itd-fade e-flex e-con e-parent\" data-id=\"af73bda\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t<div class=\"elementor-element elementor-element-ead533e e-con-full e-flex e-con e-parent\" data-id=\"ead533e\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-58889f8 itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"58889f8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">The top-down method<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5150b6f itd-h1 elementor-widget elementor-widget-heading\" data-id=\"5150b6f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h1 class=\"elementor-heading-title elementor-size-default\">Building from the ground floor down.<\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-2744f76 e-con-full e-flex e-con e-parent\" data-id=\"2744f76\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-09030b5 itd-lead elementor-widget elementor-widget-text-editor\" data-id=\"09030b5\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>The structure and the excavation support are built together, from ground level down to the foundation. The main structure holds back the soil itself, so the separate excavation-support stage disappears.<\/p>\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-ae24cb5 e-con-full itd-pane itd-reveal itd-parallax e-flex e-con e-parent\" data-id=\"ae24cb5\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-bbadc28 elementor-widget elementor-widget-image\" data-id=\"bbadc28\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"1080\" height=\"1920\" src=\"https:\/\/irantopdown.com\/en\/wp-content\/uploads\/2026\/10\/top-down-construction-site-6.webp\" class=\"attachment-full size-full wp-image-46\" alt=\"Top-down construction in progress \u2013 Irantopdown project site\" srcset=\"https:\/\/irantopdown.com\/en\/wp-content\/uploads\/2026\/10\/top-down-construction-site-6.webp 1080w, https:\/\/irantopdown.com\/en\/wp-content\/uploads\/2026\/10\/top-down-construction-site-6-169x300.webp 169w, https:\/\/irantopdown.com\/en\/wp-content\/uploads\/2026\/10\/top-down-construction-site-6-576x1024.webp 576w, https:\/\/irantopdown.com\/en\/wp-content\/uploads\/2026\/10\/top-down-construction-site-6-768x1365.webp 768w, https:\/\/irantopdown.com\/en\/wp-content\/uploads\/2026\/10\/top-down-construction-site-6-864x1536.webp 864w\" sizes=\"(max-width: 1080px) 100vw, 1080px\" \/>\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\t<\/div>\n\t\t\t\t<\/section>\n\t\t<section class=\"elementor-element elementor-element-703f923 e-con-boxed itd-section e-flex e-con e-parent\" data-id=\"703f923\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-26a1e45 e-con-full itd-fade e-flex e-con e-parent\" data-id=\"26a1e45\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-d96f485 itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"d96f485\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">The sequence<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-de5c043 itd-h2 elementor-widget elementor-widget-heading\" data-id=\"de5c043\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Five steps. One structure doing two jobs.<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-328b0dd e-con-full itd-stagger itd-steps-grid e-grid e-con e-parent\" data-id=\"328b0dd\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t<div class=\"elementor-element elementor-element-c070e5a e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"c070e5a\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-a9685ce itd-big elementor-widget elementor-widget-heading\" data-id=\"a9685ce\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">01<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8667e74 itd-h3 elementor-widget elementor-widget-heading\" data-id=\"8667e74\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Piles &amp; precast columns<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fbc2de7 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"fbc2de7\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Shafts are drilled from ground level and piles cast. Precast columns are lowered in and set to exact position and plumb.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-bae05b7 e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"bae05b7\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-5c67b5a itd-big elementor-widget elementor-widget-heading\" data-id=\"5c67b5a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">02<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-49ee4f8 itd-h3 elementor-widget elementor-widget-heading\" data-id=\"49ee4f8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Ground-floor slab<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4e3bcd3 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"4e3bcd3\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>The first slab closes over the site and props the perimeter walls from the very start.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-94226e9 e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"94226e9\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-ceea91a itd-big elementor-widget elementor-widget-heading\" data-id=\"ceea91a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">03<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e6ee969 itd-h3 elementor-widget elementor-widget-heading\" data-id=\"e6ee969\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Dig beneath, slab by slab<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-13b517a itd-text elementor-widget elementor-widget-text-editor\" data-id=\"13b517a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Soil is removed through slab openings while each basement slab and wall is cast.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-f00e463 e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"f00e463\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-418cff0 itd-big elementor-widget elementor-widget-heading\" data-id=\"418cff0\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">04<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a7a420d itd-h3 elementor-widget elementor-widget-heading\" data-id=\"a7a420d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Rise at the same time<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a11d04d itd-text elementor-widget elementor-widget-text-editor\" data-id=\"a11d04d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>With the ground slab in place, the floors above ground go up while the basements are dug.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-0d46978 e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"0d46978\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-4d40a60 itd-big elementor-widget elementor-widget-heading\" data-id=\"4d40a60\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">05<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7b8e3b2 itd-h3 elementor-widget elementor-widget-heading\" data-id=\"7b8e3b2\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Foundation last<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6e891ff itd-text elementor-widget elementor-widget-text-editor\" data-id=\"6e891ff\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>The raft is cast at the bottom. Until then the piles carry the loads; afterwards they share them.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/section>\n\t\t<section class=\"elementor-element elementor-element-9f72f98 e-con-boxed itd-section e-flex e-con e-parent\" data-id=\"9f72f98\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-d15d13e e-con-full itd-fade e-flex e-con e-parent\" data-id=\"d15d13e\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-29b5e9e itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"29b5e9e\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">Top-down vs. conventional<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-947891a itd-h2 elementor-widget elementor-widget-heading\" data-id=\"947891a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Why temporary shoring is a risk you don\u2019t need.<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c438aa9 itd-lead elementor-widget elementor-widget-text-editor\" data-id=\"c438aa9\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Without support you can only dig safely to the foundation level of the neighbouring buildings. Deeper than that, failed support can bring adjacent buildings into the excavation, with heavy losses and months of legal disputes.<\/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-71d0990 itd-fade elementor-widget elementor-widget-html\" data-id=\"71d0990\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t\t<div class=\"itd-table-wrap\"><table class=\"itd-table\"><thead><tr><th><\/th><th>Conventional methods<\/th><th style=\"color:var(--itd-bronze)\">Top-down<\/th><\/tr><\/thead><tbody><tr><td>Excavation support<\/td><td>Temporary: nailing, anchors, soldier piles or trusses<\/td><td>The permanent structure itself<\/td><\/tr><tr><td>Neighbours<\/td><td>Anchors often extend under adjacent plots, so consent is needed<\/td><td>Work stays inside the boundary, so no consent is needed<\/td><\/tr><tr><td>Programme<\/td><td>Excavate first, then build<\/td><td>Basements go down while the floors above go up<\/td><\/tr><tr><td>Cost, 3\u20134 basements<\/td><td>Baseline<\/td><td>~10% below nailing or anchors, ~30% below trusses<\/td><\/tr><tr><td>Going deeper<\/td><td>Trusses stop being practical<\/td><td>The saving grows with each extra level<\/td><\/tr><tr><td>Weather<\/td><td>Open excavation is exposed<\/td><td>Work continues beneath completed slabs<\/td><\/tr><\/tbody><\/table><\/div>\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/section>\n\t\t<section class=\"elementor-element elementor-element-970f40e e-con-boxed itd-section e-flex e-con e-parent\" data-id=\"970f40e\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-53d7004 e-con-full itd-fade e-flex e-con e-parent\" data-id=\"53d7004\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-915647e itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"915647e\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">Advantages<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-605e6c8 itd-h3 elementor-widget elementor-widget-heading\" data-id=\"605e6c8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">What top-down gives you.<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8a0501a itd-text itd-list elementor-widget elementor-widget-text-editor\" data-id=\"8a0501a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>\u2713&nbsp;&nbsp;No legal consent needed from neighbours<\/p><p>\u2713&nbsp;&nbsp;High excavation safety at every stage<\/p><p>\u2713&nbsp;&nbsp;No separate excavation-support stage<\/p><p>\u2713&nbsp;&nbsp;Basement and upper floors built at the same time<\/p><p>\u2713&nbsp;&nbsp;Works with concrete, steel and composite systems<\/p><p>\u2713&nbsp;&nbsp;Possible in weak or saturated soils with special measures<\/p><p>\u2713&nbsp;&nbsp;The first slab covers the excavation early<\/p><p>\u2713&nbsp;&nbsp;Site set-up leaves the street sooner<\/p><p>\u2713&nbsp;&nbsp;Work below the slabs continues in any weather<\/p><p>\u2713&nbsp;&nbsp;Basement concrete is cast under cover<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-eeac731 e-con-full itd-card-plain itd-fade e-flex e-con e-parent\" data-id=\"eeac731\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-8b09a5b itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"8b09a5b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">What it demands<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a921c9f itd-h3 elementor-widget elementor-widget-heading\" data-id=\"a921c9f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Why expertise matters.<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-402e9e2 itd-text itd-list elementor-widget elementor-widget-text-editor\" data-id=\"402e9e2\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Stage-by-stage checks of structure and excavation<\/p><p>An experienced specialist design-and-build team<\/p><p>Careful planning of the excavation<\/p><p>Slower digging through slab openings<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-77efa30 itd-lead elementor-widget elementor-widget-text-editor\" data-id=\"77efa30\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>That is why we handle the design, the precast columns and the construction ourselves.<\/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<\/section>\n\t\t<section class=\"elementor-element elementor-element-1b183bf e-con-boxed itd-section e-flex e-con e-parent\" data-id=\"1b183bf\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-6b24c4b e-con-full itd-sticky e-flex e-con e-parent\" data-id=\"6b24c4b\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t<div class=\"elementor-element elementor-element-499db3e e-con-full itd-fade e-flex e-con e-parent\" data-id=\"499db3e\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-a7b5b2c itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"a7b5b2c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">Design considerations<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3405105 itd-h2 elementor-widget elementor-widget-heading\" data-id=\"3405105\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">It starts at the drawing board.<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-641d5ce itd-lead elementor-widget elementor-widget-text-editor\" data-id=\"641d5ce\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Every buried structure we build top-down goes through these checks.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-5ad3e52 e-con-full itd-card-plain e-flex e-con e-parent\" data-id=\"5ad3e52\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-0b29ff4 itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"0b29ff4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">Structural systems<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d5aca81 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"d5aca81\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Any system can be built top-down: moment frames, shear walls, braced or dual systems, in concrete, steel or composite. For basements, concrete costs less, resists fire better, needs no special coatings and lets the budget follow the stages.<\/p>\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-dace3bb e-con-full itd-stagger e-flex e-con e-parent\" data-id=\"dace3bb\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t<div class=\"elementor-element elementor-element-dbf4bff e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"dbf4bff\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-1afcacc itd-idx itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"1afcacc\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">01<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ca429a4 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"ca429a4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Define the construction and excavation sequence, refined with the geotechnical design.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-1e0a069 e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"1e0a069\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-eadddc4 itd-idx itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"eadddc4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">02<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-95e4ee9 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"95e4ee9\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Model the ground in 2D or 3D, including neighbouring buildings and surcharges.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-a7e198e e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"a7e198e\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-5ea22df itd-idx itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"5ea22df\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">03<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-be0e0d7 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"be0e0d7\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Run every stage in the geotechnical model: soil and wall movements, earth pressures, spring properties.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-505e8f5 e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"505e8f5\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-225bd70 itd-idx itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"225bd70\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">04<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e0b3286 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"e0b3286\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Check the structural model at each stage with the matching earth pressures.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-78f3424 e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"78f3424\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-d3fc7d0 itd-idx itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"d3fc7d0\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">05<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-55f380c itd-text elementor-widget elementor-widget-text-editor\" data-id=\"55f380c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Size each pile for the floors built before the foundation is cast.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-5a3bf2f e-con-full itd-benefit e-flex e-con e-parent\" data-id=\"5a3bf2f\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-cbd220f itd-idx itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"cbd220f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">06<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c9a6de2 itd-text elementor-widget elementor-widget-text-editor\" data-id=\"c9a6de2\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p>Set a safe excavation depth and width for every stage.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/section>\n\t\t<section class=\"elementor-element elementor-element-b5da3b0 e-con-boxed itd-section e-flex e-con e-parent\" data-id=\"b5da3b0\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-048b658 e-con-full itd-sticky e-flex e-con e-parent\" data-id=\"048b658\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t<div class=\"elementor-element elementor-element-fd25141 e-con-full itd-fade e-flex e-con e-parent\" data-id=\"fd25141\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-110ea9b itd-eyebrow elementor-widget elementor-widget-heading\" data-id=\"110ea9b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<p class=\"elementor-heading-title elementor-size-default\">FAQ<\/p>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-afb685f itd-h2 elementor-widget elementor-widget-heading\" data-id=\"afb685f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Questions engineers and owners ask us.<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-637682f e-con-full e-flex e-con e-parent\" data-id=\"637682f\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-ccda2d3 itd-btn itd-btn--ghost elementor-widget elementor-widget-button\" data-id=\"ccda2d3\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"button.default\">\n\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-button elementor-button-link elementor-size-sm\" href=\"https:\/\/irantopdown.com\/en\/contact\/\">\n\t\t\t\t\t\t<span class=\"elementor-button-content-wrapper\">\n\t\t\t\t\t\t\t\t\t<span class=\"elementor-button-text\">Ask your own question<\/span>\n\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/a>\n\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-3d3e1f6 e-con-full e-flex e-con e-parent\" data-id=\"3d3e1f6\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-c6eb585 itd-faq elementor-widget elementor-widget-accordion\" data-id=\"c6eb585\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"accordion.default\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion\">\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2081\" class=\"elementor-tab-title\" data-tab=\"1\" role=\"button\" aria-controls=\"elementor-tab-content-2081\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">Can buildings with a concrete frame be built top-down?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2081\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"1\" role=\"region\" aria-labelledby=\"elementor-tab-title-2081\"><p>Yes. Columns are precast as complete concrete sections and installed in pre-drilled shafts. Beams, slabs and walls are then connected to them with mechanical couplers.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2082\" class=\"elementor-tab-title\" data-tab=\"2\" role=\"button\" aria-controls=\"elementor-tab-content-2082\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">How does the cost compare with other methods?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2082\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"2\" role=\"region\" aria-labelledby=\"elementor-tab-title-2082\"><p>The structure itself costs about the same either way, so compare the excavation support. On our projects with three or four basements, top-down support has cost about 10% less than nailing or anchors and about 30% less than steel trusses, and the saving grows with depth.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2083\" class=\"elementor-tab-title\" data-tab=\"3\" role=\"button\" aria-controls=\"elementor-tab-content-2083\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">Is top-down faster?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2083\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"3\" role=\"region\" aria-labelledby=\"elementor-tab-title-2083\"><p>With good management and the right resources, yes. Once the first slab is cast, floors above and below ground are built at the same time.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2084\" class=\"elementor-tab-title\" data-tab=\"4\" role=\"button\" aria-controls=\"elementor-tab-content-2084\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">How does construction quality compare?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2084\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"4\" role=\"region\" aria-labelledby=\"elementor-tab-title-2084\"><p>The critical step is installing columns in exactly the right position and plumb. With that done, quality is reliable if key welds are made by skilled welders, one-sided formwork is well secured, pour levels are controlled and excavation plant is manoeuvrable.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2085\" class=\"elementor-tab-title\" data-tab=\"5\" role=\"button\" aria-controls=\"elementor-tab-content-2085\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">Does top-down need special equipment?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2085\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"5\" role=\"region\" aria-labelledby=\"elementor-tab-title-2085\"><p>Concrete columns are precast at the factory under special quality control, and column installation needs suitable well-head equipment. Otherwise, standard equipment and good engineering do the job.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2086\" class=\"elementor-tab-title\" data-tab=\"6\" role=\"button\" aria-controls=\"elementor-tab-content-2086\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">Why is no consent needed from the neighbours?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2086\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"6\" role=\"region\" aria-labelledby=\"elementor-tab-title-2086\"><p>All structural, excavation and support work stays inside the site boundary. Nothing extends under neighbouring properties.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2087\" class=\"elementor-tab-title\" data-tab=\"7\" role=\"button\" aria-controls=\"elementor-tab-content-2087\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">Does top-down change the structural drawings?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2087\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"7\" role=\"region\" aria-labelledby=\"elementor-tab-title-2087\"><p>Up to four basement levels, usually not, once the construction stages are checked. Deeper projects may need changes, mainly to perimeter columns.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2088\" class=\"elementor-tab-title\" data-tab=\"8\" role=\"button\" aria-controls=\"elementor-tab-content-2088\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">How are beams and walls connected to precast columns?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2088\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"8\" role=\"region\" aria-labelledby=\"elementor-tab-title-2088\"><p>With mechanical anchorage, mainly couplers. Code limits on couplers at the column face apply to tension members and special frames and rarely govern below base level; proven details exist where they do.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-2089\" class=\"elementor-tab-title\" data-tab=\"9\" role=\"button\" aria-controls=\"elementor-tab-content-2089\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">Which slab system works best?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-2089\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"9\" role=\"region\" aria-labelledby=\"elementor-tab-title-2089\"><p>Any slab system can be used. For buried structures we recommend solid or voided two-way flat slabs for a better diaphragm and even distribution of lateral loads.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-20810\" class=\"elementor-tab-title\" data-tab=\"10\" role=\"button\" aria-controls=\"elementor-tab-content-20810\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">What does \u201cstaged design\u201d mean?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-20810\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"10\" role=\"region\" aria-labelledby=\"elementor-tab-title-20810\"><p>The structure must be stable at every construction stage (ASCE 37-02). In top-down work, earth pressure acts directly on the part-built structure, so each stage is predicted and checked.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<div class=\"elementor-accordion-item\">\n\t\t\t\t\t<h3 id=\"elementor-tab-title-20811\" class=\"elementor-tab-title\" data-tab=\"11\" role=\"button\" aria-controls=\"elementor-tab-content-20811\" aria-expanded=\"false\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon elementor-accordion-icon-left\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-closed\"><svg class=\"e-font-icon-svg e-fas-plus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H272V64c0-17.67-14.33-32-32-32h-32c-17.67 0-32 14.33-32 32v144H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h144v144c0 17.67 14.33 32 32 32h32c17.67 0 32-14.33 32-32V304h144c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t<span class=\"elementor-accordion-icon-opened\"><svg class=\"e-font-icon-svg e-fas-minus\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M416 208H32c-17.67 0-32 14.33-32 32v32c0 17.67 14.33 32 32 32h384c17.67 0 32-14.33 32-32v-32c0-17.67-14.33-32-32-32z\"><\/path><\/svg><\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"elementor-accordion-title\" tabindex=\"0\">How are pile sizes and lengths determined?<\/a>\n\t\t\t\t\t<\/h3>\n\t\t\t\t\t<div id=\"elementor-tab-content-20811\" class=\"elementor-tab-content elementor-clearfix\" data-tab=\"11\" role=\"region\" aria-labelledby=\"elementor-tab-title-20811\"><p>Before the raft exists, the piles carry all dead and construction loads. Their size and depth depend on the floors built before the foundation, the soil and site constraints.<\/p><\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<script type=\"application\/ld+json\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"Can buildings with a concrete frame be built top-down?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>Yes. Columns are precast as complete concrete sections and installed in pre-drilled shafts. Beams, slabs and walls are then connected to them with mechanical couplers.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"How does the cost compare with other methods?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>The structure itself costs about the same either way, so compare the excavation support. On our projects with three or four basements, top-down support has cost about 10% less than nailing or anchors and about 30% less than steel trusses, and the saving grows with depth.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"Is top-down faster?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>With good management and the right resources, yes. Once the first slab is cast, floors above and below ground are built at the same time.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"How does construction quality compare?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>The critical step is installing columns in exactly the right position and plumb. With that done, quality is reliable if key welds are made by skilled welders, one-sided formwork is well secured, pour levels are controlled and excavation plant is manoeuvrable.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"Does top-down need special equipment?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>Concrete columns are precast at the factory under special quality control, and column installation needs suitable well-head equipment. Otherwise, standard equipment and good engineering do the job.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"Why is no consent needed from the neighbours?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>All structural, excavation and support work stays inside the site boundary. Nothing extends under neighbouring properties.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"Does top-down change the structural drawings?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>Up to four basement levels, usually not, once the construction stages are checked. Deeper projects may need changes, mainly to perimeter columns.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"How are beams and walls connected to precast columns?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>With mechanical anchorage, mainly couplers. Code limits on couplers at the column face apply to tension members and special frames and rarely govern below base level; proven details exist where they do.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"Which slab system works best?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>Any slab system can be used. For buried structures we recommend solid or voided two-way flat slabs for a better diaphragm and even distribution of lateral loads.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"What does \\u201cstaged design\\u201d mean?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>The structure must be stable at every construction stage (ASCE 37-02). In top-down work, earth pressure acts directly on the part-built structure, so each stage is predicted and checked.<\\\/p>\"}},{\"@type\":\"Question\",\"name\":\"How are pile sizes and lengths determined?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>Before the raft exists, the piles carry all dead and construction loads. Their size and depth depend on the floors built before the foundation, the soil and site constraints.<\\\/p>\"}}]}<\/script>\n\t\t\t\t\t<\/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\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>The top-down method Building from the ground floor down. In top-down construction, the structure and the excavation support are built together, starting at ground level and working down to the foundation. The main structure holds back the excavation itself, so the separate excavation-support stage disappears. The sequence Five steps, one structure doing two jobs. 01 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"elementor_header_footer","meta":{"footnotes":""},"class_list":["post-136","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/pages\/136","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/comments?post=136"}],"version-history":[{"count":11,"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/pages\/136\/revisions"}],"predecessor-version":[{"id":214,"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/pages\/136\/revisions\/214"}],"wp:attachment":[{"href":"https:\/\/irantopdown.com\/en\/wp-json\/wp\/v2\/media?parent=136"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}