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Flat Roof Insulation

Flat roofs can be insulated from outside or within. In most cases, installing insulation with new plasterboard slabs and a vapour control layer on the underside of the existing ceiling is the easiest solution.

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Install Flat Roof Insulation And Live In A Comfortable Atmosphere For Life

Are you worried about damp in your home? Does it get unpleasantly cold during winter? If the answer is yes, then you are going to find this article very interesting as it is all about insulation, which can help maintain a comfortable environment around your home and office. Sometimes people fall ill because of an unhealthy environment at home when there is an imbalance of temperature and ventilation, but insulation really can be a problem–solver in this regard. Flat roof insulation is a popular kind of insulation that is installed above your ceiling to ensure that the cold air remains outside and warm air inside.

You will need to know the right kind of insulation to use that is required for your home, the materials specifically chosen and the measurement of the space that is needed to be installed. If you are thinking of getting rid of mold and condensation, then you must install the right materials from the offset.

Thermal roof insulation are entirely responsible for keeping your ceiling space warm without letting cold air penetrate within the living space of your home. Flat roof insulation has been popular since the 1950s throughout the UK, and it has been providing warmth and controlling temperatures within a building. Flat roof insulation will work best for you when you are living in an area or region that records extreme temperatures. Construction companies and engineers do the process of installing the insulation during the construction stages. However if you are retrofitting the insulation in an existing house, well then it becomes a little more of a difficult job. It may require for the removal of existing plasterboard to access the flat roof area from underneath or it may require for the removal of the flat roof sheeting on the outside of the building. No matter what way you go about it in an existing building it will be a messy and dusty job.

The Benefits

1. Live in comfort

After you have successfully installed the flat roof insulation, you will notice an immediate difference within the building. Almost instantly. Products such as TR27, TR26 from Kingspan or Isover Spacesaver, Knauf Earthwool, Celotex GA4000, Celotex XR4000, Celotex Crown-Up and Celotex Crown-Fix are just some of the products you can use to install on or within a flat roof.

2. Save money

Flat roof insulation promise you the permanency of protection against the cold and will save you on your heating bills as well.

3. Complete protection

Protection is 100 % assured from external elements, as there will be no infiltration of any sort if you go with an air tight option. You may also stay protected from sound pollution and will be able to enjoy a peaceful environment around your home.

4. Longevity

Flat roof insulation has a very long lifespan and will outperform the lifetime of the building in which it is installed in. Hence the importance of installing these products correctly. You can spend alot of money on insulation but if it is not installed correctly then it will not work.

5. Affordable prices

Flat roof insulation is available at affordable prices both in the online and offline market. You need to keep in mind how many m2 of insulation you require and the thickness of the materials to be used.

Flat Roof insulation is necessary for all houses because it provides you with the care and comfort, that you cannot find anywhere else. These are very efficient materials but can also be delicate so be careful when handling them. They are very easy to install, however it is better to call for a professional when you are planning to install these around your home as if it is not done correctly it might as well not be there.

Flat roof insulation is very popular, especially in colder regions like the UK and Ireland where it can become difficult to trap heat. This is a form of internal wall insulation with great thermal capacity unlike any other. If you are looking for thermal insulation, then Insulation4less will be the right choice as we have a wide range of thermal insulation with great prices. You can contact the sales team, and they will help you out regarding the appropriate quantity, type, and size that you need for your space.


Mineralwool Flat roof insulation is very much capable of preventing sound and noise externally, the material that they are made of has from basalt rock and glass has brilliant capacity to sustain and withhold sound. This is one of the significant criteria if you are living in a busier neighborhood and hence you need these acoustic insulation products to maintain a peaceful environment around your house. Sound absorption is a major function of Flat roof insulation.


Most of us show concern for a fireproof insulation when we plan to reside or live in a house. It is simply a paramount concern regarding safety. Well, if you are worried about fireproofing, then the solution to your problem is simple and easy to overcome, i.e. mineral wool flat roof insulation, coupled with plasterboard on the inside will help to ensure a safe home in the event of a fire.


The key issue affects the very fabric of our house and it occurs because of the meeting of warm air with a colder surface. Most houses face the issue of condensation and damp due to high humidity and moisture levels in the environment of the house. Condensation can also occur from the household environment from cooking, showers, baths even people breathing. If you do not have adequate insulation and ventilation then condensation will become an issue very quickly.

Not enough depth for your flat roof insulation?

If you find yourself with a tight space in which you have to insulate then sometimes it is best to turn your attention to a number of factors.

Insulate above the flat roof section using Kingspan TR27 or Celotex Crown-Up of crown-Fix or similar.
Use a high performance Phenolic insulation like Kingspan K110 or Kingspam TP10 maybe. Both of which will give great U-values.
Make the flat roof space as airtight as possible to avoid any unnecessary breeze from entering into the house from outside.
Use an insulated panel like Celotex PL4000 or Warmline insulated plasterboards. All of which will again improve the performance of your flat roof area.
Include some ventilation around your roof space to avoid the build up of condensation in an area in which you cannot see.

Obviously you will want to go a thick as possible with your insulation to maximise its performance so keep that in mind when selecting the correct insulation that suits your needs.

Another option for an extremely high performing insulation is to use Kingspan Optim-R range. This is an extremely expensive option, however by far and above the best. Achieve incredible U-values that cannot be achieved with such thin insulation. prices start at roughly £100m2 so keep this in mind when you think you may use it, as the price very quickly racks up.

Do you need to vent a flat roof?

It is definitely recommended that you ventilate a flat roof and in fact the regulations state that you should leave a 50mm gap between the insulation and the underside of the roof covering. This is the case for a warm roof space and a cold roof space. It is also recommended that you install a vapour control layer to control the movement of air around the roof space. The last thing you want is a gale force wind blowing through your house because you have ventilated your roof space and all that wind is making its way into the house.

The different types of vents that can be used can the brick vents if you can install them in a wall somewhere or tile vents which can be installed on the roof. Another alternative would be soffit vents and there are loads of options on the market to choose from.

How do you insulate a flat roof?

First off all you need to lay 12mm OSB or Plywood down on the ceiling joists. Its best to screw these down with brass of galvanised screws so they will not decay over time. Then install your vapour control layer to control the movement of air within the building and assist in reducing the buildup of condensation. Lay your rigid insulation material over your vapour barrier and ensure you have marked where your vapour barrier is being punctured and install a good Butyl tape in these locations before you fit your insulation. Lay a second layer of OSB or plywood over the insulation and fix the deck down with the appropriate fixings. Then install your final finish of a waterproof coating which can be torch on felt, fiberglass tanking or similar to completely make your flat roof watertight.

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