We’ll help you figure out what type of attic or attic insulation to choose, how much it costs, whether you can get it for free, and how much you can save by insulating your roof.
Do you have a flat or pitched roof?
Which insulation to choose depends on the type of roof you have.
- Pitched roof – There are two options: warm or cold loft insulation.
- Flat roof – There are three options available: warm deck, cold deck or inverted roof.
Cold roof insulation for pitched roofs
The simplest and cheapest roof insulation is the classic cold loft variant. The insulation is installed above and between the wooden beams above the ceiling of the top floor of your house. That is often just mentioned .
It prevents the heat from escaping the living area of your home, but the attic remains uninsulated. So it stays cold in winter and warm in summer.
As a DIY project, it’s pretty easy, and you can buy loft insulation from most hardware stores.
Cold roof insulation is the only roof insulation that you can apply for in order to have the costs covered by a grant. Click here to learn more about insulation grants.
Warm attic insulation for pitched roofs
If you cannot install cold attic insulation, for example because you are using your attic as living space, you must consider warm attic insulation.
For a warm attic, lay the insulation directly under the roof in the level of the roof slope (slope). The insulation reduces heat loss and your attic won’t get excessively hot in summer or cold in winter.
It’s not as straightforward as laying rolls of insulation, but it can still be done as a home improvement if you’d rather not pay a plumber.
An important point to keep in mind with a warm attic solution is the need for ventilation right under the roof tiles. This prevents condensation from forming or water from penetrating through or around the roof tiles and causing the roof structure to rot.
Types of warm loft insulation
For insulation under the roof, insulation mats made of mineral or glass wool are used, which are held by wooden slats on and over the rafters. Alternatively, Styrofoam panels (partially laminated with foil) can also be installed. These usually have to be tailored.
Another option is EPS squeeze products (expanded polystyrene). These are made in the shape of an accordion, which pops open when pushed open.
Spray foams are mostly installed professionally, but are also available as a DIY measure. Alternatively, spray foam can be used to provide additional physical strength when a roof is not in the best condition – as it helps hold the structure together. Missing or slipped tiles must be fixed before the foam insulation is applied. Find out how much Cost and whether it is suitable for your home.
Flat roof insulation
There are three types of flat roof insulation and a professional should help you decide which is best for you.
- Warm deck or warm roof has insulation over the roof terrace (the slab under the roofing, which is usually made of wood). It is recommended in damp and cold areas like the UK.
- Cold deck or cold roof has insulation under the roof terrace and the associated beams. Typically, you leave a gap for ventilation, as condensation can form, which can lead to rot. In both the warm deck and cold deck options, the weather membrane (usually made of roofing felt and bitumen) is the top layer and protects against rain.
- Inverted roof has insulation that goes over the weather membrane and effectively protects it from heat and cold, which can shorten its lifespan and that of the roof terrace. It can even protect against wear and tear if there is access to the roof. On an inverted roof, the top layer is usually gravel or a similar material.
A good time to insulate a roof is when it is being replaced, although in many cases a roof in good condition can be retrofitted with insulation.
You almost always have to hire a professional plumber to install your flat roof insulation and there are no energy grants to help you with the costs. Can you use which? Trusted dealer to help you find a recommended local dealer.
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