Go back
Spray Foam Insulation

Loft Insulation Thickness: The Essential Guide To Heatproofing

Loft Insulation Thickness: The Essential Guide To Heatproofing

When it comes to your attic, you probably use it primarily for storage, if for anything at all, and that’s likely because it’s cold and a bit dingy, with floorboards housing scratchy and unpleasant fibreglass insulation panels and stuffing.

Contrary to popular belief, there’s no specific loft insulations thickness regulations as such – and as with so many things in life, it’s quality, not quantity that counts.

With that in mind, here’s our essential guide to heatproofing your loft, proving that there are far more fundamental factors than thickness, that should determine your overall insulation decision…

How Thick are Most Loft Insulations?

The most traditional and popular form of loft insulation is fibreglass panels and stuffing. This is either squares or rolls made up of tightly wound fibreglass strands. It looks like candyfloss but is dangerous and scratchy to touch.

Traditional fibreglass insulation is normally found in between the floorboards of lofts and attics. This unfortunately leaves the area above it without insulation, and so often too cold to utilise as a living space.

Fibreglass insulation when stuffed or laid between the floorboards of lofts or attics range from 5 to 10 inches thick, with the floorboards added on. This can make for quite a considerable space to lose!

How Thick Should Loft Insulations Be?

The thickness of insulation is not necessarily a demonstration of its value. Instead, the quality of the insulation should be considered.

Loft insulation such as fibreglass padding degrades over time, and, consequently, needs replacing. It also absorbs a degree of water and moisture, and whilst it will dry out, is virtually ineffective while wet.

As a result, however thick your loft insulation is, unless it is of high quality, and able to minimise thermal bridging, it will not be of benefit to your home.

What is the Most Effective Loft Insulation Product?

The most effective insulation product on the market is spray foam insulation, an industrial chemical foam that is the market leader in colder countries, such as Canada, Norway and Sweden.

As a foam, rather than a roll of padding, it spreads to fill a surface or area before it dries and solidifies, creating a superior seal in the process. As a result, the area insulated is sealed off completely from the outside world, both in terms of temperature and moisture.

Spray foam insulation is completely impermeable to water and air flow, so provides the perfect barrier for the home.

Loft Insulation Thickness : The Essential Guide To Heatproofing

Spray foam insulation is completely impermeable to water and air flow, so provides the perfect barrier for the home-and saves you substantial cash whilst it's at it!

How Thick is Spray Foam When Used In Lofts?

The thickness of spray foam insulation is dependent on the area to be insulated, and the individual building requirements, but in the majority of cases, needs not be more than a few inches thick.

However, the thickness of spray foam insulation does not impact on an attic room in the same way that traditional fibreglass insulation does – as it does not lie in the same place. Rather than being laid in the floor of the room, it is instead sprayed directly onto the interior of the roof, in between the roofing rafters.

This frees up the floor and the depth of up to ten inches within the room, as well as keeping the room itself warm and comfortable enough for it to function as a living space.

How Is Spray Foam Installed In A Loft?

Spray foam insulation must be installed by a specialist technician with the relevant qualifications and experience. Here at Home Logic, our talented team of technicians are all British Board of Agrement accredited 

One of our licensed contractors can visit your home ahead of installation, to discuss options, and make application and thickness recommendations, bespoke to your property and situation.

Discover how spray foam insulation could benefit your loftspace today by calling 0800 1700 636, or by simply clicking the button below!