Inverted Concrete Roof

Inverted roof upside down roof in an inverted roof construction the principal thermal insulation layer is located not only above the roof structure but also above the waterproofing resulting in the waterproofing structural deck and support structure being at a temperature close to that of the interior of the building.

Inverted concrete roof.

The inverted roof concept also known as protected membrane or upside down roofing ensures insulating both the water proofing membrane and the reinforced concrete slab from extreme thermal stress. This means that the insulation should be highly resistant to water absorption for example an extruded polystyrene based product which will not be affected by water or repeated freeze thaw cycles. Geo textile layer laid over insulation boards to prevent fines from reaching the membrane surface. Waterproofing layer eg singly ply membrane.

Then sarnatherm aquazone a high performance non woven polyethylene membrane is installed. Inverted roofs have their waterproofing layer beneath the insulation instead of above it as in other forms of roofing. In an inverted roof construction the sika trocal and sika sarnafil single ply membranes sikalastic liquid applied membeanes or sikabit bitumen membranes are installed directly to the structural deck usually concrete. This is achieved by placing isoboard extruded polystyrene insulation board above instead of below the waterproofing membrane.

Inverted roof internal to external roof build up. On top of the waterproofing layer sikatherm insulation xps is installed. Now that we understand what an inverted roof is and some of the benefits we ve put together a listed build up to help make designing your roof that bit simpler. Inverted roofs are a type of warm flat roof where the insulation is above the waterproofing layer.

Most of the inverted roof insulation boards have an a or a rating but as an inverted roof is usually on a concrete deck the overall rating will be c or d. Ballast should consist of paving slabs or of rounded pebbles of minimum diameter 19mm to the depth specified in the design. An inverted roof also referred to as a protected membrane or upside down roof is form of flat roof in which the waterproofing layer is beneath the thermal insulation rather than above it. Inverted warm roof concrete deck not suitable for slopes greater than 10 ballast.

In this issue the investigations team explains how inverted roofs work outlines their benefits warns of a possible cause of problems and describes an unusual investigation. The waterproofing layer is typically a liquid applied membrane above a concrete roof slab.