Easy to install insulation and prevents heat from escaping through the roof.
Fills the gaps between wall cavities to help to help keep your home warmer
Insulation in your converted roof space creates a blanket effect to trap heat within the home
Can be installed in properties that have a suspended floor or a cavity underneath
Provides an option for properties that do not have any wall cavities by adding insulation to internal walls
A useful option for solid walled properties unable to benefit from cavity wall insulation
Spray foam, also known as spray polyurethane foam, is a type of insulation that is sprayed into a certain area and then expands to fill the space. The result is insulation that fills almost every crevice and has a cloud-like appearance, although the texture is much more solid than traditional foam.
There are two types of spray foam – closed cell and open cell. Closed cell spray foam is dense and solid, and you don’t need a particularly thick layer to see effective results in terms of increased thermal efficiency. As the name suggests, it’s made up of entirely closed components, which result in the density.
It’s thanks to this density that closed cell spray foam is able to insulate your property so effectively, almost entirely trapping heat without gaps to allow it to escape.
Both open and closed cell spray foam have similar advantages and disadvantages, but there are some clear distinctions that differentiate the two. Closed cell is a more rigid solid and much denser than open cell. That means to achieve a layer of insulation that’s as effective as closed cell, you’d have to install more open cell spray foam.
Although closed cell is pricier than open cell, the extra layers of open cell you’d need to install somewhat cancel out these cost savings.
Closed cell spray foam is considered a better insulator than open cell because it does a better job of preventing heat from escaping thanks to its density. Unfortunately, this also acts as a barrier to moisture, which can cause damp issues.
While open cell spray foam might not be quite as good at preventing heat from escaping, it’s a great form of acoustic insulation, significantly reducing the noise from neighbouring properties or other rooms in the home.
There’s no one better option than the other – both have their benefits and drawbacks. If you’re concerned about damp or noise reduction, open cell might be a better option, while closed cell is the obvious choice if improving thermal efficiency is your number one priority.
Here’s where things get a little more complicated with spray foam. Spray foam has been installed in homes for over 30 years now, but in recent decades there have been worries about the safety of spray foam in the home.
Because spray foam insulation creates such a tight seal, much more heat is kept in, and there’s a lot less ventilation than you might experience with other forms of insulation. Unfortunately, by retaining so much heat with little ventilation, spray foam can create the ideal environment for damp and mould to flourish.
Not only are damp and mould terrible for the health of the home’s residents, but they can even rot the roof timbers, leading to long-term damage to the property’s structural integrity.
As a result, some lenders refuse to give mortgages for homes that have spray foam insulation fitted and some valuers will reduce the value of a home if they find spray foam during a survey.
Lenders and valuers are working with the spray foam industry to solve this problem, but it does mean you should think twice about getting spray foam insulation installed just before you plan on selling a house. Luckily, open cell spray foam allows your loft space to ‘breathe’ more effectively, so it doesn’t experience as many damp issues as the closed cell alternative.
That being said, it’s still worth checking with an expert before you have this insulation installed and make sure you get all the necessary paperwork if you decide to go ahead.
Spray foam is one of the most expensive types of insulation on the market, but open cell is the cheaper option out of the two. While spray foam in general varies from around £20 to £50 per square metre, open cell spray foam is at the lower end of that price range.
On top of the price of the material, you’ll need to consider labour costs, too. Unfortunately, there’s no option to install spray foam yourself, so you’ll need to call in the pros for this.
You can expect to pay up to £350 for an installer to visit your home and fit open cell spray foam insulation, and this price will vary in part as a result of where you are in the country. The southeast is much more expensive than the north, for example. Luckily, open cell spray foam shouldn’t take more than one day to install, provided that you’re not insulating your entire home.
If you’re looking for a more budget-friendly alternative, blanket insulation (which comes in rolls, slabs, and batts) is significantly cheaper. Plus, it can be installed as a DIY project.
The downside of blanket insulation is that it’s not great for hard-to-reach spaces or inaccessible lofts. In that situation, loose-fill is a better alternative to spray foam as it can be blown into small spaces using specialist equipment.
There are plenty of things to consider before going ahead with open cell spray foam insulation. While the advice is currently mixed on the impact of spray foam on property values, it might be worth pursuing a different type of insulation if you plan on selling your home in the near future. If you’re happy to wait for the dispute to be resolved, then installing spray foam to enjoy its range of benefits might work for you. Ultimately, it’s your call.
If you’re set on installing spray foam, working with a trustworthy installer is key. Luckily, we know just where you can find one of those! Using our contractor finder tool, you can access quotes for insulation from installers that cover your area. If you need more information, check out online reviews and testimonials or ask them for qualifications or examples of previous work.
Experienced installers will be able to accurately assess your space and establish whether spray foam is suitable. If it isn’t, an expert installer will help you find an appropriate alternative.
While it’s true that spray foam can cause issues with your property value, it remains an incredibly effective form of insulation, with a high R-value and the ability to seal a space airtight without letting heat escape. If you plan on staying in the same property for a long time and therefore aren’t worried about the value of your property decreasing, it can be a good option.
If you’re looking to find an insulation installer in your area, it’s never been easier, with our contractor finder tool. Simply type in your postcode and you’ll gain access to quotes from a whole host of reliable suppliers and installers in your area. For added peace of mind, search for online testimonials and reviews or examples of previous work. You could even get an up to £1,500 spray foam voucher with some of our partners, making the installation even cheaper!
If you’re not interested in installing open cell spray foam, you can find insulation installers for plenty of other types of insulating materials on our site, too.
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