Insulating a Flat Roof...

Improved thermal efficiency has positive effects on the environment through reduced energy usage. There are different options with their own benefits depending on whether you are constructing a warm roof or inverted roof, the useage of the building, and what the project requirements are.

The insulation for flat roofs is commonly produced as rigid boards making them easy to handle and install with the variety of waterproofing types and systems. Ordinarily, polyisocyanurate (PIR) insulation is used within warm roof construction as it has excellent dimensional stability and compressive strength, which enables it to withstand foot traffic without depression. Within an inverted roof construction the insulation needs to be able to endure a ‘buried’ scenario beneath ballast or a green roof without detriment to its properties or insulating capability; and so forms of polystyrene are utilised.

Bauder Warm Roof Insulation

BauderPIR is both strong and inert and has a goodcompressive strength making it suitable for all kinds of load bearing decks in warm roof construction.

BauderPIR FA G16 is a lightweight, convenient, easy to install and cost-effective alternative method of providing falls to a roof instead of incorporating them into the structure.

BauderVIP TE is a vacuum insulation panel designed to provide high thermal performance in areas with limited installation height and is ideally suited for roof terrace applications. 

BauderROCK is our mineral fibre insulation with exceptional acoustic and fire resistance properties. The insulant is considerably heavier than PIR and may not be suitable for all warm roof constructions.

BauderGLAS is a cellular glass insulation that gives high compressive performance.


Fire performance of warm roof insulations

Within a warm roof waterproofing system for TS1187 Test 4, the insulation, be it mineral wool, cellular glass or PIR, is not directly exposed and is therefore determined by the performance of the cap sheet and its system classification; thus these insulants all conform to Building Regulations in the same way – not one achieving a higher rating than the other.

Bauder inverted roof insulation

Our Expanded Polystyrene and Extruded Polystyrene inverted roof insulations are designed to sit on top of our waterproofing systems. Our XPS and EPS inverted insulation options include BauderJFRI PREMIUM+BauderJFRI PREMIUM (300)BauderXPS (300)BauderXPS upstand insulationBauderXPS WFRL and BauderJFRI WFRL.

We also offer BauderGLAS inverted insulation and BauderROCK NC 56mm which are non-combustible insulations which achieve Euroclass A1 rating. 

Inverted insulation is always ballasted to stabilise it against wind uplift and flotation which can comprise items such as pebbles, paving or a green roof. 

Fire performance of inverted insulations

Bauder inverted insulation is specified in buried scenarios and are fully covered with paving slabs etc and meet current Building Regulations without testing, again with the exception of being used in the construction of a 'Specified Attachment'.