Inverted Flat Roof System

Inverted roofs are designed with the waterproofing layer usually a liquid applied membrane beneath the insulation.

Inverted flat roof system.

Then aquazone a high performance non woven polyethylene membrane is installed over the insulation to minimise the cooling effect associated with rainwater flowing down through the insulation and draining away. Rigid extruded polystyrene insulation has minimal water absorption due to its closed cell structure. What is an inverted roof. Invented by dow in the late 1960 s an inverted roof system uses dupont styrofoam brand xps insulation to protect the membrane helping improve the performance and longevity of the entire roof system.

In an inverted roof construction the sika trocal membrane is installed directly to the structural decking usually concrete and the innobond thermal insulation is installed on top of the membrane. 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. The main difference between inverted roof systems and other roof systems is in the position of the waterproofing membrane. An inverted roof is quite simply where the waterproofing layer is installed over the structural deck rather than over the insulation.

Inverted flat roof waterproofing combined with a thermal insulation is essential for a buildings waterproofing and energy saving thermal insulation. The upside down sequence means the deck is waterproofed first then insulated and finally finished with paving or ballast. This makes it the only material suitable and approved for inverted roof applications. Insulation boards are loose laid on top of the membrane and then weighted down with paving slabs or gravel ballast.