Floor Insulation

We have a wide range of floor insulation boards, slabs, and foils on offer, as well as the fittings and fixtures required to install them safely and effectively, such as Foil Tape, Perimeter Edging Strip, and Vibration Dampening Strip. We supply top brands like Celotex, Kingspan, Quinntherm, Knauf and Rockwool, so come and browse our selection of floor insulation below.

Our floor insulation products are ideal for insulating underfloor, concrete, suspended, or simple floor areas and will save you money on your energy bills as well as increasing the comfort in your home by reducing heat loss and providing acoustic insulation too.

Products such as SuperFOIL SFUF can save you time, effort, and money over traditional forms of floor insulation, as well as being ideal for areas where you’re tight on space. They control air leakage brilliantly, and their foil covering reflects heat to keep it inside the home more effectively than most non-foil faced products. You can buy foil rolls, or purchase foil faced insulation board. The Kingspan Kooltherm K103 Floorboard is a top seller, ideal for use with concrete or timber floors.

You might also be interested in our Rockwool Slab Insulation, which offers great acoustic, thermal and fire insulation. Available in different thicknesses and densities, and with great ‘green’ credentials, there’s a Rockwool slab for every floor insulation job.

Find the products you need by filtering by Category, Brand, and Thickness on the left-hand side of our page. If you need help and would like to discuss the different products available, contact us by phone on 020 3582 6399 or Live Chat , or Read Our Guide.

Celotex TB4000 Thermal Bridging Board 1.2m x 2.4m - 25mm to 40mm
Celotex TB4000 Thermal Bridging Board 1.2m x 2.4m - All Sizes Floor Insulation
Vendor
Celotex
Regular price
from £14.03 £16.84
Sale price
from £14.03 £16.84
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£0.00
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Celotex GA4000 General Purpose PIR Insulation Board 50mm to 100mm 2.4m x 1.2m
Celotex GA4000 General Purpose PIR Insulation Board 1.2m x 2.4m - All Sizes Floor Insulation
Vendor
Celotex
Regular price
from £14.03 £16.84
Sale price
from £14.03 £16.84
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£0.00
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Celotex XR4000 Insulation Board 1.2m x 2.4m - 110mm to 200mm
Celotex XR4000 Insulation Board 1.2m x 2.4m - All Sizes Loft Insulation
Vendor
Celotex
Regular price
from £44.54 £53.45
Sale price
from £44.54 £53.45
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£0.00
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25mm Celotex TB4025 2.4m x 1.2m
25mm Celotex TB4025 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£14.03 £16.84
Sale price
£14.03 £16.84
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£0.00
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40mm Celotex TB4040 2.4m x 1.2m
40mm Celotex TB4040 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£19.17 £23.00
Sale price
£19.17 £23.00
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30mm Celotex TB4030 2.4m x 1.2m
30mm Celotex TB4030 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£16.30 £19.56
Sale price
£16.30 £19.56
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£0.00
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50mm Celotex GA4050 2.4m x 1.2m
50mm Celotex GA4050 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£19.39 £23.27
Sale price
£19.39 £23.27
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100mm Celotex GA4100 2.4m x 1.2m
100mm Celotex GA4100 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£35.19 £42.23
Sale price
£35.19 £42.23
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80mm Celotex GA4080 2.4m x 1.2m
80mm Celotex GA4080 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£32.84 £39.41
Sale price
£32.84 £39.41
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£0.00
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90mm Celotex GA4090 2.4m x 1.2m
90mm Celotex GA4090 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£35.00 £42.00
Sale price
£35.00 £42.00
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60mm Celotex GA4060 2.4m x 1.2m
60mm Celotex GA4060 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£24.62 £29.54
Sale price
£24.62 £29.54
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£0.00
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70mm Celotex GA4070 2.4m x 1.2m
70mm Celotex GA4070 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£28.00 £33.60
Sale price
£28.00 £33.60
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£0.00
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75mm Celotex GA4075 2.4m x 1.2m
75mm Celotex GA4075 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£28.64 £34.37
Sale price
£28.64 £34.37
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£0.00
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120mm Celotex XR4120 2.4m x 1.2m
120mm Celotex XR4120 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£46.26 £55.51
Sale price
£46.26 £55.51
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£0.00
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150mm Celotex XR4150 2.4m X 1.2m
150mm Celotex XR4150 2.4m X 1.2m Floor Insulation
Vendor
Celotex
Regular price
£55.88 £67.06
Sale price
£55.88 £67.06
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140mm Celotex XR4140 Insulation Board 2.4m x 1.2m
140mm Celotex XR4140 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£55.25 £66.30
Sale price
£55.25 £66.30
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110mm Celotex XR4110 2.4m x 1.2m
110mm Celotex XR4110 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£44.54 £53.45
Sale price
£44.54 £53.45
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£0.00
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130mm Celotex XR4130 2.4m x 1.2m
130mm Celotex XR4130 2.4m x 1.2m Floor Insulation
Vendor
Celotex
Regular price
£55.02 £66.02
Sale price
£55.02 £66.02
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Celotex CW4000 Cavity Wall Insulation Board 450mm x 1200mm - All Sizes
Celotex CW4000 Cavity Wall Insulation Board 450mm x 1200mm - All Sizes Cavity wall Insulation
Vendor
Celotex
Regular price
from £0.00 £0.00
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from £0.00 £0.00
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£0.00
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Kingspan Thermafloor TF70 Floor Board (All Sizes) 2.4m x 1.2m
Kingspan Thermafloor TF70 Floor Board 1.2m x 2.4m - All Sizes Floor Insulation
Vendor
Kingspan
Regular price
from £122.76 £147.31
Sale price
from £122.76 £147.31
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£0.00
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EcoTherm Eco-versal Insulation Board (2.4m x 1.2m) - All Sizes
Eco-versal (2.4m x 1.2m) - All Sizes Floor Insulation
Vendor
Ecotherm
Regular price
from £18.07 £21.68
Sale price
from £18.07 £21.68
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£0.00
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Mannok Insulation Board 1.2m x 2.4m (All Sizes)
Mannok Insulation Board 1.2m x 2.4m (All Sizes) Floor Insulation
Vendor
Mannok
Regular price
from £18.84 £22.61
Sale price
from £18.84 £22.61
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£0.00
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Recticel Eurothane GP (2.4m x 1.2m) All Sizes
Recticel Eurothane GP (2.4m x 1.2m) All Sizes Insulation
Vendor
Recticel
Regular price
from £14.13 £16.96
Sale price
from £14.13 £16.96
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£0.00
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Danosa Danopren TR XPS Insulation 600mm x 1250mm - All Sizes
Danosa Danopren TR XPS Insulation 600mm x 1250mm - All Sizes Floor Insulation
Vendor
Danosa
Regular price
from £35.17 £42.20
Sale price
from £35.17 £42.20
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£0.00
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Danosa 75mm XPS Concrete Slab Grey - 500mm x 500mm
Danosa 75mm XPS Concrete Slab Grey - 500mm x 500mm Flat Roof Insulation
Vendor
Danosa
Regular price
£6.41 £7.69
Sale price
£6.41 £7.69
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£0.00
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Greenguard GG300 1.25m x 0.6m - All Sizes
Greenguard (Styrozone) GG300 (1.25m x 0.6m) All Sizes Wall Insulation
Vendor
Kingspan
Regular price
from £0.00 £0.00
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from £0.00 £0.00
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£0.00
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GreenGuard GG500 600mm x 1250mm - All Sizes
GreenGuard (Styrozone) GG500 600mm x 1250mm - All Sizes Floor Insulation
Vendor
Kingspan
Regular price
from £8.46 £10.15
Sale price
from £8.46 £10.15
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£0.00
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GreenGuard GG700 600mm x 1250mm - All Sizes
GreenGuard (Styrozone) GG700 600mm x 1250mm - All Sizes Wall Insulation
Vendor
Kingspan
Regular price
£0.00 £0.00
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£0.00 £0.00
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£0.00
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Fibran 300L 1250mm x 600mm (All Sizes)
Fibran 300L 1250mm x 600mm (All Sizes) Floor Insulation
Vendor
Fibran
Regular price
from £35.17 £42.20
Sale price
from £35.17 £42.20
Regular price
£0.00
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Basf Styrodur Xps (1265mm x 615mm) All Sizes
BASF Styrodur XPS (1265mm x 615mm) All Sizes Insulation Board
Vendor
BASF
Regular price
from £78.02 £93.62
Sale price
from £78.02 £93.62
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£0.00
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Thin-R 2.4m x 1.2m (All Sizes)
Thin-R 2.4m x 1.2m (All Sizes) Floor Insulation
Vendor
Xtratherm
Regular price
from £0.00 £0.00
Sale price
from £0.00 £0.00
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£0.00
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Foil Tape 75mm x 45m
Foil Tape 75mm x 45m Floor Insulation
Vendor
Insulation4Less
Regular price
£10.87 £13.04
Sale price
£10.87 £13.04
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£0.00
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What do you need to know about Floor Insulation?

Floor insulation refers to insulation placed beneath the floorboards. The primary purpose is to reduce heat loss, as up to 20% of heat can escape through the floor into the ground

In addition to the floor, you will also need to insulate the gaps between the floor and skirting boards as well. This is helpful in reducing draughts.

Obviously the best time to install floor insulation is while a new floor is put into place, even though floors can also be retrofitted with insulation. Not only will this reduce heat escaping but also save a large amount on your heating bill.

Should the floor be insulated?

Usually, people focus on insulating attics and exterior walls. Although it is important to insulate these areas, you can save a lot of money on your heating costs if you insulate your floors as well.

Basement floor insulation or underfloor insulation takes many different forms. And, if your house does not have basements and unheated cellars, then floor insulation will further reduce your overall energy bill.

The first reason is that it will help getting rid of drafts from your house. Not only will it prevent drafts from penetrating through the gaps between the floor and the ground but it will also reduce heat escaping from them. In this regard, we recommend installing rigid insulation panels, particularly between the floor joists.

If you have wooden floors, they can get deteriorated or damaged due to the accumulation of moisture. This can be avoided by putting a layer of insulation between the crawl space and the floor – in order to create a vapor barrier, which will prevent moisture from soaking your wooden floor.

Solid Floor insulation can also provide extra protection to the piping system beneath the floors during cold winters.

Because pipes are placed under the floor, an insulated floor can significantly lower the risks of pipe bursting during the winter season.

Benefits of Floor Insulation

Just by filling the gaps between the floor and skirting boards, you can save between £25 to £30 pounds per year.

In addition, with floor insulation you can reduce your carbon footprint up to 240kg per year and 100kg when you opt to fill the gaps between the skirting boards and floor.

By slowing down the movement of heat, your house will stay warmer for longer during winter and cooler in the summer months.

The underfloor insulation for wooden floors can save you about £60 pounds per year. This means recouping the cost within 2 years.

Keep in mind when installing your floor insulation

Whether you get a contractor or you plan to do the work yourself, the existing floorboards, carpets and furniture will have to be removed. This is a good time to check for signs of dampness or moisture and apply the necessary fixes.

So allow some budget to carry out the additional work if necessary.

Budget your Floor Insulation

Regardless of the size of your floors, the cost of hiring a professional shouldn’t vary too much. Unless your house screams “I’m rich, look at my big floors!” you shouldn't be in for a big surprise.

  • Professional installation: roughly from £800 to £1000 to hire a contractor.
  • Do it yourself: the cost of materials is around £150 for an average house including the material for skirting boards & gaps to fill.

Put a £100 aside in case your underfloor needs some TLC.

Type of insulation for your floors

You have many options to choose from, but we will just mention the most popular ones.

  • Blanket insulation (rolls or batts)
  • Mineral Wool
  • Foam Board
  • Rigid board

What is the minimum thickness for floor insulation?

According to UK building regulations, the thickness differs according to the type of floor, the shape, size, and construction. However, the minimum thickness is 150mm for mineral wool and about 90 mm for rigid foam insulation. Whatever you choose you need to achieve a U value of 0.25.

Most builders will opt for rigid foam insulation between the floor joist as you can fit them tightly and ensure no gaps are left.

What kind of insulation for suspended floors?

If you want to insulate the area between the crawl space and the floor joists, it is best to choose a breathable insulation such as fiberglass or mineral wool with a breather membrane on the cold side to reduce drafts and a vapour barrier on the warm side (above). Make sure you have good subfloor ventilation, the airflow between the ground and the timber joists is necessary to avoid dampness and rot. However this airflow can increase draughts if the floor is not properly insulated. Making sure your contractor gets the ventilation right will be key to the success of your insulation. So don’t hesitate to ask those questions, and contact previous customers as well, as plenty can go wrong with floor insulation.

Can I insulate on top of floorboards?

The simple answer to this question is “Yes,” you can insulate on top of floorboards. Usually a damp proof membrane is laid out before installing rigid foam boards.

However, you need to understand that the insulation can be done at the time of replacing the floorboards. This can likewise be done if you have rigid floor insulation on the top.

In the UK, in some old homes, you will find suspended timber floors – and the insulation of such floors is usually done when you lift the floorboards and lay the insulation material between the joists. The best insulation material for timber floors is mineral wool insulation.

Do I need insulation between floors?

In general, you don’t need to insulate between the floors. You only need the insulation of the ground floor. Also, you don’t need insulation of your floor space if you live on the upper floor.

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