{"id":3805,"date":"2021-02-02T15:46:35","date_gmt":"2021-02-02T14:46:35","guid":{"rendered":"https:\/\/ravagobuildingsolutions.com\/hu\/?p=3805"},"modified":"2021-08-24T08:51:16","modified_gmt":"2021-08-24T06:51:16","slug":"inverted-flat-roof-winter-construction-challenges","status":"publish","type":"post","link":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/3805\/inverted-flat-roof-winter-construction-challenges\/","title":{"rendered":"Inverted flat roof – winter construction challenges"},"content":{"rendered":"\n

In winter, the <\/strong>building <\/strong>contractors <\/strong>have to<\/strong> face difficulties caused by the cold, and materials for construction are also limited.<\/strong> <\/p>\n\n\n\n

I<\/strong>nverted flat roofs can be<\/strong> built <\/strong>in all seasons. Construction will not stop in inclement weather conditions<\/strong>. <\/strong>Construction work in cold weather always requires greater preparation, which in some cases can result in additional costs.<\/strong> <\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

The advantage of inverted flat roofs is that, after the waterproofing has been completed, the thermal insulation layer and the ballast layer can be prepared in almost any weather conditions, as they are not sensitive to severe weather. RAVATHERM XPS closed cell extruded polystyrene foam is easy to install in cold weather thanks to its frost and water resistance properties, thus providing a much more flexible schedule for construction work. However, other structures of the inverted flat roof need to be given special attention.<\/p>\n\n\n\n

The general layer order of the inverted flat roof (from top to bottom): <\/p>\n\n\n\n

-ballast (e.g. gravel)
-drainage or filter separation layer (water resistant film or geotextile)
-RAVATHERM XPS closed cell polystyrene foam thermal insulation layer
-waterproofing (e.g. bituminous plate)
-slope structure
-load-bearing structure (usually reinforced concrete)<\/p>\n\n\n\n

If the temperature falls below +5 \u00b0C, special preparations are required. In this case, most building materials need to be preheated, but between 0 and -5 degrees the structures must be protected separately from cold, as the risk of frost would be increased. At lower temperatures, work should only be started where absolutely necessary, and the structures must be continuously heated all the time.<\/p>\n\n\n\n

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What to pay attention to during construction of the different layers of inverted flat roof:<\/p>\n\n\n\n

Reinforced concrete<\/p>\n\n\n\n

The construction of a flat roof in winter requires special attention, as the large reinforced concrete load-bearing structure is made by mixing concrete, cement, water and additives. From the point of view of the cold, it is important to know that although it produces heat when hardening, it does not protect itself from frost. A solution to this problem can be the use of special cements whose solidification is associated with higher thermal emission. If necessary, we can work with hardening accelerators and\/or antifreeze additives. By covering the finished horizontal concrete surface with temporary thermal insulation, it can be protected from the dangers of subzero temperatures and frost. During the construction process, dilation of the slab sections must be ensured.<\/p>\n\n\n\n

Waterproofing<\/p>\n\n\n\n

During the waterproofing of building structures, cold weather significantly limits the range of materials that can be used. SBS-modified bitumen products must be used for waterproofing against any precipitations. Today’s modern glass fabric and polyester veil insert SBS-modified plates remain flexible, they are stronger and less sensitive to movement even in cold weather. It is important to note that even in cold weather, only an SBS solvent emulsion can be used as preparation.<\/p>\n\n\n\n

Waterproofing can only be carried out in dry weather, the temperature of the air and the base layer should preferably exceed +5 \u00b0C. When used in colder weather, the product must be stored in a warm, dry space (at a temperature of min. 12 \u00b0C) for 24 hours prior to installation. In rainy or snowy weather, or on wet or ice-covered substrates, insulation work cannot be carried out.<\/p>\n\n\n\n

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Thermal insulation<\/p>\n\n\n\n

RAVATHERM XPS products have antifreeze properties due to their closed cell structure and do not take up water, so there is no need to worry about deterioration of the quality of the material during installation. However, when operating in extreme cold weather, the thermal expansion associated with subsequent temperature changes cannot be ignored. The linear thermal expansion coefficent of extruded polystyrene foam is 0,07 mm\/mK, which means that when warming from -5 \u00b0C to +20 \u00b0C, the boards may expand by up to 1,5 – 1,75 mm lengthwise. Therefore, under 0 \u00b0C, it is worth laying the insulation plates loosely in order to avoid excessive pressure of the boards during normal “operating” temperatures. In some cases there may be tension along the extremeties of the boards which may damage the structure of the perimeter wall as a result of side pressure.<\/p>\n\n\n\n

It is also recommended in cold weather to use extruded polystyrene foam with a special concrete layer on the perimeter walls. The use of lightweight, one-step, UV-protected surface boards allow you to skip applying the moisture-absorbing plaster surface. The boards are fixed with polyurethane adhesive foam or with mechanical fixings.<\/p>\n\n\n\n

It is important to note that the high-thickness RAVATHERM XPS thermal insulation boards can be used in one layer only to meet the strict thermal requirements for flat roofs. For more information, please contact our sales consultant colleagues or write a message.<\/p>\n","protected":false},"excerpt":{"rendered":"

In winter, the building contractors have to face difficulties caused by the cold, and materials for construction are also limited.  Inverted flat roofs can be built in all seasons. Construction will not stop in inclement weather…<\/p>\n","protected":false},"author":13,"featured_media":3725,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[2],"tags":[],"class_list":{"0":"post-3805","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-news","8":"entry"},"acf":[],"_links":{"self":[{"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/posts\/3805","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/comments?post=3805"}],"version-history":[{"count":1,"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/posts\/3805\/revisions"}],"predecessor-version":[{"id":4561,"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/posts\/3805\/revisions\/4561"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/media\/3725"}],"wp:attachment":[{"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/media?parent=3805"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/categories?post=3805"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ravagobuildingsolutions.com\/hu\/en\/wp-json\/wp\/v2\/tags?post=3805"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}