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Problems With Spray Foam In Attics: How To Prevent Them


Insulation has to be one the most cost effective and easy ways to improve your home. Not only will it provide a way to reduce the amount of money you spend on energy, but it will improve the way your home feels in both the summer and the winter. 

Spray foam insulation is one example of the types of insulation we can use and it has many advantages - however there can be some drawbacks when it is used in attics. 

Making sure you take these into account will ensure that your spray foam insulation works exactly as it should.

The Energy Saving Trust estimates that a home that has been insulated properly to a depth of 270mm or its equivalent can save as much as £300 per year on energy bills. 

This represents a significant saving on an average energy bill of around £1200 per year. With an investment that starts at just a few hundred pounds, this can offer great value for money.


What Is Spray Foam Insulation?

Spray foam insulation is a mixture of two chemicals that when forced together under pressure will expand into a foam many times its original liquid state. 

This spray foam will then harden into an inert substance that is both strong and highly insulative as well as being entirely safe.

It can be used in all kinds of applications from filling small holes to covering entire walls and the underside of your roof to create an impenetrable seal.

The advantages of spray foam insulation are many. It is completely waterproof, so even if it becomes wet, it will not lose any of its insulative qualities. This compares to mineral wool insulation which will fail to work effectively if it becomes wet and doesn’t dry out. 

Spray foam is also highly flexible and can be used in all kinds of hard to reach spaces - including the inside of walls, small crawl spaces and other areas where it may be hard to gain access.

Spray foam insulation is also known to work well for upwards of 30 years and has been used in the US and Canada for more than 50 years. 

The foam can be used to add structure to buildings and can even offer high levels of sound-proofing. This makes it versatile and well worth the extra you may need to spend.


How Is Spray Foam Used In My Attic?

The attic is the best place to add insulation in your home. As we all know, warm air rises, therefore the heat that you generate inside your home will automatically make its way into your loft or attic space.

You have a choice when it comes to insulating your loft - either add insulation to the floor between the attic and the house or add spray foam insulation to the underside of the roof. 

The latter allows the attic to maintain an even temperature and can give you the opportunity to use the attic space as a room, while the former will tend to lead to the attic being very cold in the winter and very warm in the summer.

Your contractor will simply spray the foam directly onto the underside of your rafters in an even coat. This can then be trimmed and covered if you wish or left as it is. The coat will usually be around 100mm thick and this compares to the 270mm that is recommended for other types of insulation. 

You will get an excellent thermal value and find that even this smaller volume of material provides excellent insulation. 100mm of coverage allows you to maintain the head height in your loft - something that is lost when 270mm of mineral wool is used on the floor.

Spray foam is also easy to apply to your attic and can be added in just one day by an expert contractor. You will appreciate the fact that your home will be warmer in no time and you will get the full benefits straight away.


Are There Any Drawbacks To Using Spray Foam In My Attic?

Not everything is perfect and even spray foam insulation can have its issues, however with the right contractor and application process, you can usually avoid any disadvantages that you might come across. The most common issues that you might face are the following:

Low Quality Foam:

If your contractor is willing to cut corners and use a low grade foam mix, you may find that it crumbles or does not provide the protection that you want. In particular it may be affected by damp and mould.

The key is to ensure that you have chosen a contractor with a good reputation and one that uses high quality materials.

Damp And Ventilation Issues:

Some people do report that their home suffers with damp issues after application of spray foam insulation. This is usually due to an imbalance in temperatures inside the attic compared to the rest of the house. As the attic cools the air may condensate, causing problems.

The right kind of ventilation is essential to prevent this and once again your contractor will be able to advise. The use of open cell spray foam insulation will allow the space to breathe and prevent any build up of moisture.

Gaps And Holes:

Poor installation can mean that your attic insulation has gaps and holes. These will allow water to seep in and for warm air to get out.

Once again your contractor needs to be highly experienced to know where issues might comes from and to use the right techniques to gain access to all of the attic spaces. Complicated roof structures will make the job harder, but not impossible.


What's The Best Way To Prevent These Problems?

By choosing the right contractor! The right contractor will understand the weather conditions in your area, the structure of your roof, how the attic may need ventilation and they will use the very best materials. 

Always try to find a contractor that can offer you good advice and can provide examples of work they have already completed. 

Spray foam insulation is one of the best ways to insulate your home and is becoming more and more popular, for very good reasons. As long as you follow the guidelines above, you can avoid the issues that you might encounter.