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Insulating your home well is essential to maintaining pleasant temperatures and ensuring energy efficiency. Insulation boards can be a great solution for insulating roofs, floors and walls, with an array of options.
Confused by the difference between PIR and PUR, or EPS and XPS?
Read on to find out the strengths of various insulation boards, where to buy them and how they are best applied around the home.
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Insulation boards are rigid boards or sheets made of foamed polystyrene, polyurethane, polyisocyanurate, or gypsum.
Their rigid, closed-cell structures provide better insulation compared to traditional wool insulation.
They can be used to insulate a roof, wall or floor, and prevent heat from escaping the property.
Three key benefits of using insulation board are:
If you aren’t sure where to start with improving your insulation, read our guide to how to insulate your home.
If you’re looking to prevent sound from escaping alongside heat, these are some effective types of insulation that can be installed in the walls, in the form of boards:
Alongside fitting insulation boards and other insulating materials, consider our advice on how to draughtproof your home to further prevent heat escaping.
As there are a huge variety of types of insulation board, and for each time a range of styles and thicknesses, this table is not an exhaustive list of available retailers or products.
However, it should give you an indication of what to look for, some of the shops and brands that are available, and how much you might expect to pay for different materials and sizes.
All dimensions are length x width x thickness. Price data collected from retailer websites 2nd February 2024.
Expanded or extruded polystyrene insulation boards are best suited for floor insulation. As they will be installed underneath the supporting floor, the boards need good compressive strength to handle heavy loads without breaking.
The heat-loss impact of polystyrene boards is slightly less than plastic variants, so a thicker layer of boards may be needed.
For more details on how to insulate your flooring read our guide to floor insulation options and cost.
PIR or polystyrene insulation boards are both suitable for insulating walls. If you have a stud wall, PIR boards are likely to be the better option.
For internal walls, you can try using insulated plasterboards for a lightweight, effective barrier to block heat disappearing from different rooms.
Find out everything you need to know about insulating different types of walls in our guides to cavity wall insulation and cavity wall insulation costs and savings.
Insulation board can be used for both pitched and flat roofs. Once cut to size, they are placed either above or under the roof rafters or between ceiling joists, creating a barrier in any space where heat can be lost.
The best type of insulation boards to use in a roof are PIR, but PUR could be used for flat roofs. Alternatively, try lightweight insulated plasterboards.
Our roof insulation types explained article will tell you the difference between insulating a pitched roof and a flat roof, and whether you should install cold or warm loft insulation.
If you are a confident DIYer and have a few tools and skills, it may be possible to install insulation board yourself.
There are two common methods used to fit insulation boards:
If for peace of mind you’d rather hire a professional, you can use our Which? Trusted Trader tool to find a reliable trader near you:
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