Inverted Membrane Roof System

Inverted roof membrane assembly irma offer superior protection of the roof membrane from foot traffic and mechanical damage.

Inverted membrane roof system. An inverted roof also known sometimes as a protected membrane or pmr roof uses the same materials as a conventional roof but places insulation on the top of the membrane. Irma can be referred to as an insulated roof membrane assembly. The upside down sequence means the deck is waterproofed first then insulated and finally finished with paving or ballast. Inverted roof systems a variation of a warm roof.

Inverted roof membrane assembly irma systems are used in applications where the membrane requires protection from site specific hazards. Rigid extruded polystyrene insulation has minimal water absorption due to its closed cell structure. An inverted roof is quite simply where the waterproofing layer is installed over the structural deck rather than over the insulation. Insulation boards are loose laid on top of the membrane and then weighted down with paving slabs or gravel ballast.

This makes it the only material suitable and approved for inverted roof applications. The main difference between inverted roof systems and other roof systems is in the position of the waterproofing membrane. Some references may use the term protected membrane roof or pmr system. These systems are typically applied in conditions where there is extensive roof traffic or to protect from excessive weather conditions such as multiple hail events.

In an inverted membrane system the coventional membrane arrangement is invereted or turned upside down. In an irma the system s insulation is installed above the waterproofing membrane instead of below as in a conventional roof assembly. Also known as a protected membrane or upside down roof inverted roofs employ insulation which can resist water absorption provide excellent thermal performance be unaffected by freeze and thaw cycles withstand surface traffic and be protected from uv and mechanical damage among others. These systems are typically applied in conditions where there is extensive roof traffic or to protect from excessive weather conditions such as multiple hail events.

Inverted roof membrance assembly irma systems are used in applications where the membrane requires protection from site specific hazards. The inverted waterproofing insulation system is applicable for all types of flat roofs as it offers an efficient solution for new construction but also for renovation of old flat roofs as is it possible to install an inverted roof over an existing roof build up. Inverted roofs are designed with the waterproofing layer usually a liquid applied membrane beneath the insulation. 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.