
Flat Roof Constructions
We investigate the different types of flat roof construction
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There are lots of important factors to consider when installing a flat roof, from thickness of materials to making the most of your budget. We can offer a number of insulation solutions to meet the requirements of your specific project.
Our Flat Roof Insulation Solutions
Material | Advantages | Products |
|---|---|---|
Vacuum Insulation Panels (VIPs) | Suited to applications where there may be a requirement for both low U-values and the thinnest possible roof build-up Problem solver for where a lack of construction depth or space is an issue Optimum performance with a declared thermal conductivity of just 0.007 W/mK Design service for your specific roof For use with most fully adhered single-ply waterproofing membranes |
PIR | High performance insulation - thermal conductivities as low as 0.022 W/mK Fully compatible with most mechanically fixed single-ply waterproofing systems Compatible with most green roof systems Installation technique is ideal for fast track building programmes Easy to handle and install compared to some other commonly used insulants | Thermaroof TR24 - for use with partially bonded torch-applied multi-layer bituminous waterproofing Thermaroof TR26Â - for use with mechanically fixed single-ply waterproofing Thermaroof TR27Â - for use with fully adhered single-ply, partially bonded built-up felt, mastic asphalt and cold liquid applied waterproofing |
Rigid Extruded Polystyrene(XPS) | Ideal for car park decks High compressive strength withstands vehicle laods Minimal water absorption Withstands freeze/thaw cycling Easy to handle and install compared to some other commonly used insulants | Kingspan GreenGuard GG300 -compressive strength of 300 kPa Kingspan GreenGuard GG500Â - compressive strength of 500 kPa Kingspan GreenGuard GG700Â - compressive strength of 700 kPa |
Rock mineral fibre | A1 Euroclass Fully compatible with most mechanically fixed single-ply waterproofing systems  |
Easily compare how the use of different materials, or thicknesses of materials, can impact the overall thermal performance of a building. This helps to ensure you specify and install the right insulation thickness and set clear construction targets.


Book an in-person or virtual CPD to find out more about the different types of flat roof constructions, including regulations and code of practice.
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Thermaroof TR24
Insulation for flat roofs with partially bonded torch applied waterproofingThermaroof TR26
High performance flat roof insulation for mechanically fixed systemsThermaroof TR27
High performance flat roof insulation for adhered and bonded systemsKingspan GreenGuard GG300
Rigid extruded polystyrene (XPS) insulationKingspan GreenGuard GG500
Rigid extruded polystyrene (XPS) insulationKingspan GreenGuard GG700
Rigid extruded polystyrene (XPS) insulation