Inverted Roofing

Opposed to a traditional Flat Roof, an Inverted Roofing System consists of an ‘Upside Down’ Flat Roof in which the Waterproofing Layer is beneath the Thermal Insulation. This is also commonly known within the industry as a ‘Protected Membrane’. Inverted Roofs allow the insulation to protect the Roof’s membrane from extreme weather conditions, such as frost, high UV exposure and contraction expansion that is caused by extreme summer and winter temperatures.

Inverted Roofs, sometimes referred to as ‘Upside Down Roofs’ or ‘Protected Membrane Roofs’ are becoming more popular as an alternative to traditional Roofing Systems due to their reversed design – where the Waterproofing layer lies below the Insulation rather than above it – and the subsequent benefits that follow.

The Waterproofing Layer is typically made up of a Liquid Applied Membrane above a concrete slab on top of the structural deck. This tends to be a quick and efficient installation as the insulation is easy to apply over the Waterproofing Layer. The Insulation is then weighted down with paving slabs or gravel ballast. Because of this design, the Inverted Roof is protected from traffic on the Roof, such as footfall and equipment, meaning it is ultra-durable.

The design of an Inverted Roofing System comes with other advantages, such as;

• Being a Long-Term solution – Inverted Roofs have a long-life span
• Inverted Roofs protect against Thermal Shocks – Preventing aged and fatigued Waterproof Membranes
• Cost-effective solution due to lower maintenance costs and reduced energy costs
• Excellent for stormwater management
• Waterproof Layer acts as a vapour barrier – eliminating the risk of condensation
• A lot of the materials that constructs an Inverted Roof can be reused

One of the main advantages of an Inverted Roof System is the protection of the Waterproofing Membrane by the Insulation layer. This is down to the changes in weather conditions which causes the expansion and contraction of the Insulation.