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How To Insulate Dormer Roof For The Long-Term

How To Insulate Dormer Roof For The Long-Term

In this article we aim to help answer the questions: How to insulate dormer roof for the long term... Let's get right into it

Are you one of those homeowners who have utilised the roof space of your home with a dormer roof? Even though dormer roofs are great, the problem is that they were previously constructed with not much insulation, resulting in internal conditions that are far from conducive to comfort.

Did you know that insulating your dormer roof can help you to significantly cut down on your energy bills? In fact, after insulation, you can also make better use of the dormer room during Winter, as it will remain toasty enough to be used as a guest room.

Now to the actual question – how can you insulate a dormer roof? Given below are 3 of the most popular methods by which you can insulate your dormer roof, and the best way to tackle this task to achieve the desired results. Let’s begin!

Dormer Option No.1: Rigid Insulation

The rigid insulation method requires the utilisation of 150mm thick insulation in between the rafters, along with a 50mm air gap in order to avert cold bridging. In case the space on the existing rafters is not enough, you can fix a batten to the rafters’ underside in order to enhance the depth.

Between 0.020 and 0.023 W/m K is the thermal conductivity of the product, and it will keep your dormer room quite warm.

Dormer Option No.2: Spray Foam Insulation

Spray foam insulation is a relative newcomer to UK shores, although it has been used in Canadian homes for over 30 years to date.

The primary advantage that spray foam insulation has over other insulation methods is that it can be applied in hard to reach spaces, and enables a building to breathe, enabling adequate ventilation.

This type of insulation does not need an air gap, and can be applied in areas that are not as easy to accommodate with traditional methods. Moreover, this material provides a superior seal-virtually eliminating all leaks in the process.

In terms of heatproofing, spray foam has a thermal conductivity of 0.032 and 0.037 W/m K.

Dormer Option No.3: Mineral Wool Insulation

This method has a thermal conductivity of 0.040 and 0.044 W/m K. It makes use of 320 to 350mm of insulation in between the rafters.

In order to attain the desired thickness of 320 to 350mm, mineral wool will have to be built up in 100mm and 150mm layers.

How To Insulate Dormer Roof For The Long-Term

Insulating your dormer roof is a worthwhile investment, and should be prepared accordingly. Always get at least 3 quotes from different companies, and check their credentials using independent review sites, such as Trustpilot

Dormer Roof Insulation: Why Spray Foam Does It Better

Out of all the above-mentioned common methods of insulating dormer roofs, the most dependable and preferred is spray foam insulation for the following reasons:

• Spray foam insulation is capable of reaching places in the dormer roof that other methods of insulation cannot.
• It is quite simple to apply spray foam insulation because all one has to do is spray. This material expands on its own, and helps one to quickly achieve the insulation needs, with installation taking less than a day.
• It does not require any air gap, and as a matter fact, it helps to cover all the tiny holes. This way, it prevents insects and rodents from entering the dormer room and nesting.
• Spray foam insulation prevents the formation of mould that makes the home a better place to be. It also gives you the opportunity to make excellent use of the dormer room, safe in the knowledge that the roof is properly insulated, and there is no chance of adverse health effects owing to mould growth and resultant spores.
• This type of insulation is ideal for already constructed properties having dormer roofs that were not insulated at the time of construction. Since there was no initial plan for insulation, your home might not even have the needed space for the other insulation methods to work.
• You will be able to save substantial money on your energy bills every month!

Now that you are all set to upgrade the insulation of your dormer roof, these 3 key considerations are well worth bearing in mind:

1. When altering the insulation of your dormer roof, you need to make sure that you are adhering to the existing building regulations.
2. The maximum elemental U-value of your roof must not exceed 0.16 W/M2 K.
3. Thermal bridging must be limited because without that, there is a high chance that the excessive heat will be lost.

Insulating your dormer roof is a worthwhile investment, and should be prepared accordingly. Always get at least 3 quotes from different companies, and check their credentials using independent review sites, such as Trustpilot.

In terms of effectiveness, the open-celled variety of spray foam offers the best results for residential projects; closed-cell formulas are better appropriated for commercial applications instead.

Transform your dormer roof into a room to remember-for all the right reasons. Take the first step to cosier conditions today, by calling 0800 1700 636, or by simply clicking the button below!