Insulation boards are loose laid on top of the membrane and then weighted down with paving slabs or gravel ballast.
Upside down roof.
In an inverted membrane system the coventional membrane arrangement is invereted or turned upside down.
Inverted membrane roof systems.
Upside down roofing faster safer easier instead of shingling from the bottom up we re shingling from the top down.
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.
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.
The so called upside down roof is simply a rearrangement of the normal elements of a roofing system to try and overcome some of the disadvantages of the conventional arrangement.