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Under floor insulation being installed beneath a suspended timber floor
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Under floor insulation, for one house or a whole programme.

A suspended timber floor lets cold air straight into the room through every gap in the boards. Insulating beneath it stops the draughts and the heat loss in one go, and we do it for homeowners and as part of whole house retrofit programmes, with residents in place.

Book a free home surveyTalk to us about a programme
TrustMark registered
Insurance backed guarantees
Our own crews, residents at home
What is under floor insulation?

Keep your home warm from the ground up

Under floor insulation involves fitting insulation material beneath the floorboards of your home. Using a certified under floor insulation system, we create a thermal barrier that prevents cold air from entering and warm air from escaping through the ground floor. Up to 15% of heat can be lost through an uninsulated floor.

Book a free home surveySee our track record →
Insulation fitted between floor joists under a timber floor
Who we do it for

One home, or a hundred.

The same crews, the same specification and the same paperwork, whether it is your house or every home on a housing provider’s programme.

Homeowners

A free survey, an itemised quote and a straight answer, including when the job is not worth doing. Then our own crew, and a certificate at the end.

  • Free survey that confirms you have a suspended timber floor and finds the access route
  • Insulation fitted between the joists from below or with boards lifted and relaid, ventilation to the void kept clear
  • Usually a day on site, 0% VAT on the insulation
  • Certificate and guarantee in your handover pack
Book a free home surveyCall 01200 407790

Housing providers, councils and main contractors

We deliver this measure as a package for funded retrofit programmes, on our own or as a subcontractor to your principal contractor, with the assessment and coordination done by our own people.

  • TrustMark registered, insurance backed guarantees, and PAS 2035 retrofit assessment and coordination done in house
  • Under floor insulation as part of a whole house package, with sub floor ventilation kept clear so the timbers stay dry
  • Surveyed and priced home by home, so the tender is measured, not estimated
  • Occupied homes as standard: residents stay in, access is planned, work is photographed before, during and after
  • Handover file for your retrofit coordinator: certificates, photos, guarantees
Talk to us about a programmeSub contracting →
Rows of terraced social housing of the kind being upgraded on the Aspire Housing whole house retrofit programme
Case study

One measure among many. Whole house retrofit, band C on every home.

Under floor insulation rarely travels alone on a programme; it is one measure in a fabric first package. That is how we run Aspire Housing’s £1.3 million whole house retrofit programme in Staffordshire as principal delivery partner: every home assessed and coordinated in house under PAS 2035, and every home upgraded in year one lifted from band D or E to band C.

£1.3m
programme value
Band C
every home, year one
4,000 kWh
up to, saved per home a year
Read the case studyAll case studies →
Benefits

Why choose under floor insulation?

Reduce Heat Loss by Up to 15%

Stop heat escaping through your ground floor with a professional insulation system.

25 Year Guarantee

Backed by an industry leading 25 year guarantee from us.

Certified insulation system

We use a certified under floor insulation system for proven, reliable performance.

Eliminates Cold Draughts

Say goodbye to cold feet and draughty floors with a complete under floor thermal barrier.

Improved Comfort Underfoot

Enjoy warmer floors and a more comfortable home environment all year round.

Our process

How we install under floor insulation

1

Free Home Survey

We assess your property to check suitability and identify the best approach for your floors.

2

Access Assessment

Suspended timber floors are required. We check access points and plan the installation route.

3

Insulation System Installed

Our certified under floor insulation system is fitted beneath your floorboards for maximum performance.

4

Floorboards Replaced

All floorboards are carefully replaced and made good so your home is left tidy and intact.

5

Quality Inspection

A full quality inspection and certification is completed before final sign off.

Our guarantee

25 year guarantee

Every under floor insulation installation is backed by an industry leading 25 year guarantee. This provides independent assurance that your insulation has been installed to the highest standards using the certified under floor insulation system.

25 Year Guarantee
Certified System
Our insulation services

Other ways to insulate your home

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Flat Roof Insulation

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Loft insulation material ready for installation

Loft Insulation

By properly insulating your loft, you will see dramatic savings in your heating bills and reduce heat loss.

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Cavity Wall Insulation

Installed by drilling a series of holes in the mortar joints of the external wall and filling the cavity.

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Internal wall insulation being installed in a home

Internal Wall Insulation

Insulating internal walls improves comfort levels while reducing energy consumption and bills.

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Room in roof loft conversion space

Room in Roof Insulation

Keeps a comfortable temperature by reducing heat loss and maximising energy efficiency.

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Ready when you are, for one floor or a whole scheme.

Homeowners get a free survey and warmer floors in a day. Housing providers and contractors get under floor insulation surveyed and coordinated within a whole house package under PAS 2035.

Book a free home surveyTalk to us about a programme Call 01200 407790
FAQs

Under floor insulation questions, answered

What type of floor can be insulated?

Under floor insulation is suitable for properties with suspended timber floors. Our surveyor will check your floor type during the free home survey to confirm suitability.

What is our under floor insulation system?

Our under floor insulation system is a certified system designed specifically for suspended timber floors. It provides exceptional thermal performance and comes with a 25 year guarantee.

Will my floors be damaged during installation?

No. Floorboards are carefully lifted, the insulation is installed beneath, and then all boards are replaced and made good. Your home is left tidy and your floors intact.

How long is the guarantee?

All under floor insulation installations come with a 25 year guarantee, providing long term peace of mind that the work has been carried out to the highest standards.

Do you work for housing associations, councils and contractors?

Yes. Under floor insulation is one of the measures in the fabric first packages we deliver for housing providers, with the retrofit assessment and coordination done in house. Aspire Housing’s whole house programme is the worked example. See the case study or our sub contracting page.

Do I need to move out?

No. Most installs are done from below through an access hatch or by lifting a run of boards in each room, and you stay in the house. Where boards are lifted we relay them the same day.

Is there funding for under floor insulation?

Funding changes often, so ask us for the current position. As of September 2026 the Warm Homes: Local Grant, run through councils, funds insulation for eligible lower income households, and social landlords have the Warm Homes: Social Housing Fund. We deliver under these programmes for councils and landlords, and we will tell a homeowner honestly whether they are likely to qualify.

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