Closed-Cell Spray Foam Insulation

Closed-cell spray foam insulation is one of the most effective and energy-efficient insulation options currently on the market. Boasting a high thermal value, it’s the perfect insulator in terms of thermal conversion for both commercial properties and residential homes.

What is Closed-Cell Foam Insulation?

As the name indicates, closed-cell spray foam insulation is made up of components that are completely closed. It is in light of this, that closed-cell insulation is the go-to product if you are looking for energy efficiency, structural integrity or water resistance.

The sheer density of the cells enable it to insulate your property to an incredibly high standard – much more so than traditional insulation materials such as polyethylene fibres, polyester, or foil.

How does closed cell insulation work?

Properties of Closed-Cell Spray Foam

Spray foam insulation has many advantages over its more traditional counterparts that make it a superior thermal insulator. With closed-cell insulation you can protect your property from the elements for years to come.


Closed Cell Foam Density

Closed-cell foam insulation has an extremely dense cellular composition – making it the ideal choice for many commercial and residential projects. This means the insulation doesn’t expand as much as open-cell insulation, but still fills all the nooks and crannies in the application area.


Water Impermeability

This cellular composition of closed-cell spray foam prevents water from passing through it, making it an effective solution for moisture and damp problems. We recommend closed-cell insulation for those in flood-risk areas.


High Thermal Density

Closed-cell foam insulation has a far better thermal value per cm than other types of insulation, providing superior temperature regulation for your property. This is due to its high foam density, while the air barrier it creates while expanding stops air transfer.



Closed-cell foam prevents moisture growth due to its water-impervious composition, which effectively increases your property’s lifespan. Therefore, closed-cell insulation offers an advantage over some traditional forms of insulation which can hold water and promote mould growth.


Quality of Air

The air quality in your property dramatically improves with closed-cell insulation, as its close density can block out any toxins, dust, and prevent the growth of mould and moisture.


Improve Building Structure

Since closed-cell spray foam sets more rigid than any other insulation type, it can improve the integrity of your building far beyond what more traditional insulation types can offer you.


Pest Proof

Rats, mice and other rodents have no interest in eating through spray foam insulation, like they would with an insulation like fibreglass. This means that no external means should impact the performance of your product in its lifespan.


25 Year Warranty

Upon completion of your spray foam application, your insulation is covered by a 25 year product warranty. This warranty comes directly from the supplier and covers the workmanship, as well as the product itself.

Closed cell Foam

Closed-Cell Spray Foam Insulation Areas of Application

Closed-cell spray foam insulation is both durable and sustainable, making it the ideal insulation solution for both commercial and residential applications. Since it is more robust in nature than its open-cell insulation counterpart, it is better suited to the following:

• Metal Buildings

• Commercial Areas such as Offices

• Pole Barns

• Basements and Crawl Spaces

• Application in Exterior Areas

How Is Closed-Cell Insulation Applied?

If you’ve ever seen open-cell insulation be applied, then closed-cell is applied in much the same way. Two pipes will run the respective elements into the spray nozzle which will mix them upon application. Upon application, they will react and begin to expand - filling the application area and providing an airtight barrier.

Fully accredited spray foam experts, such as those here at Eco Spray-Foam Systems, will be able to professionally insulate your building to the highest standard. Combined with the latest insulating technologies, and the best warranties available; closed-cell spray foam insulation is a no brainer!

Apply Closed-Cell Foam

Closed-Cell Spray Foam vs Open-Cell

Both open-cell and closed-cell spray foam insulation are highly effective insulants in their own right. However, one type can be more suited to a project than the other.

For instance, if you're looking for better thermal insulation, and want to better regulate the temperature of your property – closed-cell spray foam insulation would be the better choice. Whereas, if it’s soundproofing you require, you would be best to go for open-cell foam insulation.
Open-cell vs. closed-cell spray foam insulation

  • Adds wall racking strength and impact resistance.
  • Is ideal for continuous insulation.
  • Can be applied at very low temperatures.
  • Has lower vapour permeance.
  • Rejects bulk water (making it ideal for use in flood zones).
  • Higher tensile and bond strength.
  • Higher Thermal Value per cm (making it convenient to apply in narrow spaces).
where to get closed cell insulation supplier

Let Us Take Care of Your Closed-Cell Insulation Needs!

We have been in the industry for over two decades, and within that time have successfully completed projects across the whole of the United Kingdom, and provided expert advice to countless clients.

We are fully accredited quality spray foam insulation providers, which is one of the newest and safest insulation technologies on the market today.

Our closed-cell spray foam products are covered by a 25 year warranty from the manufacturer. So if you’re looking to invest in closed-cell foam insulation, then get in touch with us today to find out what we can do for you! Our friendly team of experts are always ready to assist in any way they can and are available on 0203 411 5188.


  • Is Closed-Cell Spray Foam Waterproof?

  • Though it doesn’t possess a waterproof rating, closed-cell insulation is water-impermeable. This means that the insulation will restrict the flow of water through it, making it ideal for use in the cavity walls of homes in flood risk areas.

  • How Strong is Closed-Cell Insulation?

  • Once fully expanded, closed-cell spray foam has a compressive strength of 15-25psi. This allows the product to be used to enhance the strength of walls, ceilings and roofs; as well as providing its thermal and water-impermeable benefits.

  • What is the U-Value of Closed-Cell Spray Foam?

  • Closed-cell spray insulation has a u-value of 0.025kW/m²K, meaning it is an elite thermal insulator. Due to its expansive capabilities, an air barrier is created - meaning that it can achieve this u-value as no air escapes. Comparatively, traditional insulation solutions that are cut just one millimetre too small can decrease the u-value by a factor of 5.

  • How Much Closed-Cell Insulation Do I Need?

  • This all depends on the structure of your property, the uses of it, and any u-value aims or regulations you have to meet. Closed-cell insulation is normally applied in 25mm increments (1mm of liquid will expand into around 25mm of foam). Our dedicated team are more than happy to talk you through the process and perform u-value calculations for your building.

  • Does Closed-Cell Foam Require a Vapour Barrier?

  • Unlike its open-cell counterpart, closed-cell spray foam is water impermeable. It is because of this that a vapour barrier is not needed as the insulation creates this on its own upon application. The majority of Eco Spray-Foam insulation options officially qualify as a Class II vapour retarder that complies with your commercial building code requirements. If you have any questions our team are happy to talk about the building regulations surrounding your insulation needs.