The Complete UK Guide
Home Insulation Guide helps UK homeowners understand the different insulation options available to improve comfort, reduce heat loss, lower energy bills, and increase EPC performance. LAMTANS Engineering provides expert retrofit guidance from our Manchester base, helping households across the UK choose suitable insulation solutions, funding routes, and energy efficiency improvements.
Start Here
Insulate before you generate. Before installing solar panels or a heat pump, insulate your home — a heat pump works best in an energy-efficient home, and insulation typically pays for itself faster than almost any other home improvement.
Roofs
Roof heat loss can account for a significant proportion of energy loss in poorly insulated homes. Improving loft insulation helps retain warmth and reduces the amount of energy needed to heat your property.
Funding availability depends on eligibility and current scheme rules; support may be partial and a top-up contribution may be required. All costs, savings and payback figures are indicative estimates only — your free survey confirms accurate figures for your home.
Walls
Cavity wall insulation involves filling the gap between the inner and outer walls of a cavity wall with insulation material. It helps reduce heat transfer through external walls, improving comfort and energy efficiency in suitable properties.
Many UK homes built between the 1920s and 1990s were constructed with cavity walls, although suitability depends on the wall condition and property design.
Funding availability depends on eligibility and current scheme rules; support may be partial and a top-up contribution may be required. All costs, savings and payback figures are indicative estimates only — your free survey confirms accurate figures for your home.
Walls
External wall insulation (EWI) is a retrofit solution designed for solid wall properties where cavity wall insulation is not suitable. Insulation boards are installed externally and finished with a protective render system to improve thermal performance, comfort and weather protection.
Many homes built before the 1920s have solid walls, although a professional assessment is recommended to confirm wall construction and the most suitable insulation approach.
Funding availability depends on eligibility and current scheme rules; support may be partial and a top-up contribution may be required. All costs, savings and payback figures are indicative estimates only — your free survey confirms accurate figures for your home.
Walls
Internal wall insulation (IWI) is a retrofit method where insulation is installed on the inside surface of external walls to reduce heat loss and improve thermal performance. It is commonly used in solid wall properties where external insulation cannot be installed due to building restrictions or design preferences.
It can be particularly suitable for listed buildings, conservation areas, or homes where homeowners want to preserve the original external appearance.
Funding availability depends on eligibility and current scheme rules; support may be partial and a top-up contribution may be required. All costs, savings and payback figures are indicative estimates only — your free survey confirms accurate figures for your home.
Floors
Underfloor insulation is a retrofit measure designed to reduce heat loss through suspended timber floors. It involves installing insulation beneath floorboards to improve comfort, reduce draughts and make homes more energy efficient.
It is particularly common in Victorian and Edwardian properties where suspended timber floors allow cold air movement beneath the home.
Funding availability depends on eligibility and current scheme rules; support may be partial and a top-up contribution may be required. All costs, savings and payback figures are indicative estimates only — your free survey confirms accurate figures for your home.
Floors
Solid floor insulation is a retrofit solution designed for homes with concrete ground floors. It improves thermal performance by adding insulation above the existing slab, helping reduce heat loss and create a more comfortable indoor environment.
It is commonly used in modern homes, extensions and properties where suspended timber floor insulation is not suitable.
Funding availability depends on eligibility and current scheme rules; support may be partial and a top-up contribution may be required. All costs, savings and payback figures are indicative estimates only — your free survey confirms accurate figures for your home.
Park Homes
Park home insulation is a specialist retrofit solution designed to improve the thermal efficiency of mobile homes and residential park homes. Because these properties have lightweight construction and different wall, roof and floor systems compared with traditional houses, they require tailored insulation approaches.
Many older park homes have limited insulation, which can lead to higher heat loss, cold surfaces and increased energy costs.
Funding availability depends on eligibility and current scheme rules; support may be partial and a top-up contribution may be required. All costs, savings and payback figures are indicative estimates only — your free survey confirms accurate figures for your home.
Indicative Guide Prices
The cost of home insulation varies depending on the property type, insulation method, installation complexity and available funding support. The table below shows indicative UK guide figures for common insulation improvements, potential savings and expected payback periods.
| Insulation Type | Indicative Cost | Typical Estimated Annual Saving | Indicative Payback | Funding Support |
|---|---|---|---|---|
| Loft insulation | £400 – £1,200 | £300 – £400 | Under 2 years | May be available if eligible |
| Cavity wall | £400 – £1,500 | £200 – £300 | Under 2 years | May be available if eligible |
| External wall | £8,000 – £30,000 | £400 – £600 | 15–20 years | Partial support may be available |
| Internal wall | £2,000 – £10,000 | £300 – £500 | 5–10 years | Partial support may be available |
| Underfloor | £500 – £3,000 | £100 – £200 | 3–5 years | May be available if eligible |
| Solid floor | £1,500 – £10,000 | £100 – £200 | 10–15 years | Partial support may be available |
| Park home | £4,000 – £8,000 | £300 – £600 | 5–10 years | May be available if eligible |
All figures are indicative estimates, not fixed prices or guarantees. Costs and savings vary depending on your property's size, existing insulation levels, energy usage and installation requirements — and funding is eligibility-dependent, may be partial, and may require a top-up contribution. A free survey is the best way to confirm the most suitable insulation solution and available funding options for your home.
Decision Guide
Choosing the right insulation depends on your home's age, construction type, existing insulation levels and where heat loss occurs. The best solution is not the same for every property — which is why a professional assessment helps identify the most effective improvements.
Do you have a loft? Is it accessible? Accessible lofts are usually the quickest, most cost-effective win.
Suspended timber or solid concrete? Each needs a different insulation approach (see the floor sections above).
We assess your property and recommend the most cost-effective measures — including which funding routes may apply to you. Everything before this is guesswork; the survey is what turns it into a plan.
Common Questions
Loft insulation can be a DIY job in simple, accessible lofts. Cavity wall, solid wall and underfloor insulation require professional installation. We recommend always using a TrustMark registered installer.
Not if installed correctly. We include vapour control layers where needed and assess your home's ventilation as part of the survey. Poorly installed insulation can cause issues — which is exactly why you should use a TrustMark registered installer working to PAS2035.
Correctly installed loft insulation is designed to last 40+ years. Cavity wall insulation is designed to last the lifetime of the building, and external and internal wall insulation systems are designed to last 30+ years. Proper installation and moisture management are what protect those lifespans.
Partial funding may be available through schemes such as ECO4 or the Warm Homes Plan if you are eligible. Funding is not guaranteed, and in some cases you may need to pay a top-up contribution. Contact us for a free, no-obligation eligibility check.
PAS2035 is the British standard for the retrofit of domestic properties. It is required for ECO4 insulation work and represents best practice in whole-house retrofit. All our insulation work is PAS2035 compliant.
Yes. We are TrustMark Registered, RECC Accredited and PAS2035 Compliant, and we deliver ECO4 eligible projects — supporting our expertise in retrofit and energy efficiency improvements.
Free Survey & Quote
Get your free, no-obligation insulation quote today — contact LAMTANS Engineering. Not sure which insulation type your home needs? Book a free survey — we'll assess your property and advise you within 72 hours following your free survey.
Free survey · No obligation · Advice within 72 hours following your free survey