Spray Foam Insulation: Your Questions Answered

Spray Foam Insulation: Your Questions Answered…

Got a question about Spray Foam insulation? Check out our question and answer session below.

Safety & Protection

Is spray foam insulation flammable? Does it pose as a fire risk?

There are very few items that won’t burn when subjected to enough heat. Spray foam is certainly not an exception to this rule and when exposed to a naked flame, it will burn. Wood will burn, metal will burn and many other items in the home will burn.

There are many different spray foam products with some that have a very poor fire rating compared to some with a very good Class 1 rating. The ratings determine how flammable a product is and how quickly it’s likely to burn if subjected to fire.

A spray foam insulation loft pre install…

The airtight seal of spray foam is what can help to work in its favour when a fire breaks out, particularly in the loft. Flames need oxygen to thrive so it’s the airtight seal of spray foam that helps it to deplete the continuous flow of oxygen. A fire may even self extinguish when the available oxygen is depleted.

We treat the safety of our customers extremely seriously and that’s why we’ve sourced the spray foam products that offer the best protection in the event of a fire. We are the only provider of these products in the UK and when considering spray foam for your property, you should always choose the installer who can protect you and your home the best.

Does Spray Foam Insulation cause the roof timbers to rot when timber is encapsulated in foam?

Spray foam has been in the UK for around 30 years and was used extensively in the 1990’s as a means to extend the life of roofs which had no vapour membrane by applying a high density closed cell spray foam direct to tile. The general consensus about roof timbers rotting as a result of spray foam insulation being applied is generally unfounded and this is because the closed cell application was often applied to a roof area once it was already in a poor state of repair with degraded timbers and battens that were often pencil thin. The closed cell application was used to add structural integrity to the roof space and prolong the life of the roof, sometimes up to 30 years.

Eventually when the roof is replaced, roofing contractors would have noticed that the rafters and battens were in a poor state and they would have naturally assumed that this is caused by the spray foam insulation, in fact, it’s likely that the roof was already in such a poor state of repair that the spray foam insulation has simply prolonged the life of the roof.

And post install….

In the modern era, spray foam insulation is now used more extensively as an insulation product and not a quick fix to prolong the life of the roof. Many spray foam products are BBA Accredited and if installed in conjunction with the BBA certificates, they offer a fantastic, low risk method to provide an exceptional airtight, thermal barrier to prevent heat loss. Spray Foams come in two types, a low density Open Cell and a high density Closed Cell. When it comes to installing these products, we firstly consider the property type, the roof make up and the property use to ascertain which product is most suitable to minimise or eliminate the risk of interstitial condensation.

Once tiles are bonded with foam they cannot be removed and it is almost impossible to repair a broken tile or slate once spray foam sealed and bonded?

The closed cell high density spray foam is an exceptional way to bond tiles and add integrity and durability to the roof space. This option should be considered very carefully before agreeing to proceed with an install direct to tile due to the fact that once installed, it is very hard to remove and replace the tiles. The roof essentially needs to be cut out in order to take tiles off and replace the roof space, however, in the meantime, a closed cell application direct to tile will give the roof a further 20-30 years worth of life.

As an insulation company, we do not actively promote bonding the closed cell insulation direct to tile but we also respect that many homeowners do not wish to invest in a new roof, particularly if they are elderly and do not see themselves being at the property for more than 15-20 years. As a result of the closed cell insulation being such a fantastic solution when sprayed direct to tile, we do sympathise with roofing contractors who eventually have to replace the roof as it becomes a much more difficult task to remove the existing roof.

Once applied direct to the underside of tiles, it is highly unlikely that roofing tiles will break from the outside unless storm damaged or damaged from impact. A 50-60mm layer of closed cell insulation to the underside of the tile will act as a very good barrier to prevent water ingress and this is why it is a popular choice as a quick fix to a degrading roof.

Will a Spray foam seal stop a roof leaking without making any roof repairs first?

When a roof is damaged to the stage where several tiles have slipped or there are large, obvious cracks in the tiles, we never recommend spraying the closed cell insulation direct to tile until the roofing tiles have been realigned and any damaged tiles have been replaced. Water ingress from above and through tiles is referred to as a negative pressure and therefore, most waterproofing barriers will fail unless the cause of the issues is firstly resolved. Whilst the closed cell insulation is not a full waterproof barrier, it is a high density product that can certainly slow or inhibit water ingress. Our preference when spraying direct to tile would be to ensure that the roof is in a good state with no major damage.

Our recommendation to any customer considering a closed cell insulation application direct to tile would be to fully consider the pro’s and con’s of our solution vs a full roof replacement (if needed). A new roof that has been fitted well is always going to be the best solution and can last in excess of 70 years.

Money Saving

Is Spray Foam expensive?

It’s the burning question on many people’s lips – “is spray foam expensive?” In our view, spray foam is an upgrade on your insulation to help you meet the modern standards of thermal performance within the home.

When compared to competing types of insulation such as fibre, the raw cost of spray foam is slightly more expensive and the physical cost of installation is also more than simply rolling out some layers of fibre insulation on the floor of your loft. Equally, whilst the price of spray foam may be around 4 times more than fibre insulation, the performance is unrivaled.


Is spray foam insulation toxic?

When spray foam insulation was first introduced into the UK, many of the different types contained HFC’s and VOC’s in the blowing agent.

Over the years, the chemical formulation of spray foam has been vastly improved to not only increase the performance but also reduce or eliminate any dangerous gases that are bad for health and the environment.

ThermoFoam is one of a select range of spray foams that uses the Honeywell Solstice blowing agent. This is a water-based product that doesn’t contain any dangerous gases before, during or after installation.

During the installation process, our applicators where protective suits and masks to ensure they are not inhaling the spray foam in its uncured, liquid state but once applied and expanded to its deemed thickness, there is no further danger to health.

The curing process takes around 20 seconds and whilst we do not allow our customers to stand within five metres of the application zone during the process, your loft will be safe to use once we’ve packed up and vacated your home.

Your newly insulated loft should be free of toxins and the finished spray foam product will be inert, meaning that it will not give off any dangerous smell, vapour or toxins.

During the installation process, we use extraction fans to remove any gaseous air from the loft space as quickly as possible, allowing you to reclaim your loft space pretty much instantly.

If you have a question you would like to see answered here, pop us an email to info@thermoprotect.co.uk or use the contact form below and we will happily answer any queries you may have!