What Is An Inverted Roof Assembly

Best of the dow chemical co.

What is an inverted roof assembly. Insulation boards are loose laid on top of the membrane and then weighted down with paving slabs or gravel ballast. Inverted roofs are designed with the waterproofing layer usually a liquid applied membrane beneath the insulation. Irma can be referred to as an insulated roof membrane assembly. Inverted roof systems are also referred to as upside down roof assembly.

It s an enconomic method for extracting. Benefits of inverted roofs. More generically others may categorize an irma or pmr system as built up roof system or bur. This assembly has produced a variety of terms such as an upside down roof or inverted roof system and in 1968 a patent was issued on the insulated roof membrane assembly irma developed by j s.

Inverted roofs have significantly lower maintenance costs than conventional low slope roofs thanks in large part to the insulation in the inverted assembly protecting the roof membrane from mechanical damage during and after construction as well as temperature extremes that cause stress. Inverted roofs typically last longer than traditional ones. Inverted roofs are typically assembeled as vegetative ballasted or plaza roofs. Inverted roof membrance assembly irma systems are used in applications where the membrane requires protection from site specific hazards.

Protected membrane roof pmr in a protected membrane roof also known as an inverted roof membrane assembly irma the insulation is installed on top of the membrane. In an irma the system s insulation is installed above the waterproofing membrane instead of below. These systems are typically applied in conditions where there is extensive roof traffic or to protect from excessive weather conditions such as. Ballast roofs are your typical inverted roof but using gravel to hold the roofing components into place.

The insulation may be exposed to water so it should have minimal water absorption characteristics. Some references may use the term protected membrane roof or pmr system. Explore each roof assembly in greater detail below or dig into the downloadable materials to learn more. Extruded polystyrene xps is the most suitable type.

In an inverted membrane system the coventional membrane arrangement is invereted or turned upside down.