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Flat roof isolation

Isolating a roof is important, especially in a country with volatile weather like the Netherlands. Heat rises, and a lot of it is lost through the roof. This costs a lot of energy, and is bad for your wallet, ánd the environment, especially in autumn and winter. When isolating a flat roof, a lot has to be taken in to account. The investment is big, but the profits even bigger. Municipalities applaud sustainability, which makes it likely you can apply for a subsidy.

Why isolate a flat roof?

Because a lot of heat, and energy, goes lost through a flat roof, it is of great important to isolate this well. You also ensure a cooler house in the summer this way. Usually roofs can be isolated from the inside. Because flat roofs give a higher risk of moisture problems, its often recommended to isolate from the outside.

Costs and efficiency roof isolation

The costs of a flat roof isolation depend on the type of roof, the surface area, inside or outside isolation, and the material needed. Often municipalities offer subsidies regarding sustainability. Isolating together with your neighbors is a good way to save on costs aswell. The efficiency of roof isolation is big; you can save a lot yearly on your energy bill.

Differences between tiled roofs and and flat roofs

Isolating a flat roof is different from isolating a tiled roof. There are different ways to isolate a flat roof: warm isolation, cold isolation, inverted isolation, and double isolation.

Flat roof inside or outside isolation

  • Warm flat roof

In warm flat roof isolation, the isolation material is applied on top of the roof. The roof is protected and will remain walkable in most cases. The roof construction will expand and shrink less aswell. Warm flat roof isolation makes the rooms right below the roof less sceptible to temperature changes aswell.

Materials and building
The isolation on a warm roof consists of multiple layers. A damp-slowing layer is added, to make sure the humid air doesnt condensate in the isolation material. After that the isolation plates are placed. The isolation plates are covered with waterproof roofing. The roof can still be finished with tiles or gravel.

  • Cold flat roof

In cold flat roof isolation the isolation material is applied to the underside of the roof. This, however, keeps the roof exposed to different weather conditions and temperature changes. This makes the roof construction shrink and expand. For this reason a cold flat roof isolation is often avoided, and only applied if warm flat roof isolation is not possible.

Materials and building
Usually, glass or stone wool is used in cold flat roof isolation. This material is applied between the beams and the roofing. In case of a concrete ceiling, the ceiling is often lowered with a wooden construction, to create space for the isolation material. This form of isolation requires protection agains humidity, to prevent moisture problems.

  • Inverted flat roof

In inverted flat roof isolation the isolation material is placed on top of the existing roofing. This way of isolating is usually applied at renovations in which the existing roofing remains intact. The isolation is not as good as warm flat roof isolation. The isolation is easy to apply, and the cost is relatively low.

Materials and building
With an inverted roof the original roofing serves as the waterproof layer. Moist resistant plates are placed on top of this, and are covered by heavy materials like gravel or tiles to keep the isolation plates in place.

  • Flat roof double isolation

Another option is to double isolate the roof, where isolation material is applied to both the inside and the outside. With double isolation, efficiency is very good, but there is a risk of condensation problems. Double isolation brings a challenge that requires craftsmanship to ensure these problems are prevented.

Existing flat roof or new roof

The isolation technique is mostly dependent on the possibilities of the roof. A new roof is often isolated as a warm flat roof. In case of an existing roof or a renovation, other isolation techniques are considered depending on which is most suitable. Roof isolation is always recommended, regardless of whether it’s a new or existing roof.

Costs roof isolation

The costs of isolating a flat roof depend on the way of isolation, the roof construction, and the used materials. The surface area and the type of roof also play a role in the costs.

Efficiency roof isolation

When isolating your roof it is important to not only look at the costs, but the return you get from it aswell. What does roof isolation give back? When you isolate you can safe a lot on the energy bill, which is good for the environment, aswell as for your wallet.

Cost savings and subsidies

If the investment cost of isolating the roof are too high, you can see if your neighbors are planning on isolating their roof aswell. This is often the case when houses were built in the same year. When you isolate your roof together, you save on travel costs, possible scaffolding rental, and isolation price per m2. You can also check with your municipality if you are eligible for a subsidy. Municipality often offer those to stimulate sustainability.

Isolating your roof is of great importance. It prevents heat loss, and ensures a more comfortable temperature in the summer. A flat roof can be isolated both from the inside, aswell as from the outside, and can even have double isolation. However it is often recommended to isolate from the outside to prevent possible condensation problems. The isolation technique depends on the roof construction and the possibilities that the roof offers. The investments of roof isolation usually earns itself back easily in savings on the energy bill.

Are you planning on isolating your flat roof, and do you want information from a professional roofer? A specialist from Trudodak would be happy to supply you with personalized advice.

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