Instant
01 · Ask
Ask the AI a follow-up
Got more questions about insulation for Heat Pump? Describe the bit you're unsure about — the AI explains options, sequencing and what to ask the renewable energy.
Insulate for a heat pump.
Insulation upgrade before HP install — bigger radiators alone don't solve cold rooms. Whole-house strategy.
✓ Updated May 2026✓ Free quotes✓ Vetted pros
20,000+UK homeowners
50,000Quotes sent
Keep going
Hire a renewables installer. MCS or no grant.
You've read the brief on insulation for Heat Pump. Now lean on us to find the right renewable energy — and stay in control of the job.
Free
02 · Read the brief
Walk in informed
Costs, timelines, pitfalls and the right questions to ask before any renewable energy starts on insulation for Heat Pump.
60 seconds
03 · Compare
Compare 3 renewable energy quotes
Itemised quotes from up to 3 local renewable energys on insulation for Heat Pump — so you can compare like-for-like, not lump sums.
✦
Get renewable energy quotes Ready when you are
Enter your postcode and get free quotes from local pros.
Top tips
Hiring a renewable energy, without the regret.
Four moves that separate a smooth job from a nightmare.
ASHP installed without insulation upgrade
Underperforms in poorly-insulated home. Cost of running unattainable.
Cheap insulation
Inadequate fitting causes cold spots. Quality fitting essential.
Vapour barriers missing
Solid wall internal insulation without VCL causes condensation.
Grant eligibility wrong
Some grants means-tested. Check eligibility before committing budget.
Costs & timeline
Know what it costs. Know when it ends.
Indicative UK ranges and what affects price.
Cost range
By job type
Inc. VAT · 2026
Source: NMT quotes
Source: NMT quotes
Loft insulation top-up (250mm)Per house
£300–£900
Cavity wall insulationPer house, blown-fill
£500–£2.5k
Solid wall external insulationPer house
£8k–£20k
Solid wall internal insulationPer house
£3.5k–£12k
Floor insulation per m²Add to slab or under floorboards
£40–£90/m²
Radiator upgrade for ASHPLarger radiators
£1.5k–£5k
!
Quote spread is typically ± 18% — always get 3 quotes.
At a glance
Infographic · VideoThe Renewable Energy briefing.
Infographic
Renewable Energy quick-view
Video guide
Renewable Energy explained
Heat pumps work best in well-insulated homes. EPC C or better recommended. Expect to pay £3,000–£15,000 for UK insulation upgrade before installing heat pump. ECO/GBIS grants may apply.
What Does the Work Involve?
EPC survey to identify weakest insulation areas. Loft insulation top-up (250-300mm). Cavity wall insulation if present. Solid wall internal or external insulation. Floor insulation. Heating element upgrades (larger radiators or UFH for ASHP). All before ASHP install.
Typical Costs
| Item | Low (£) | High (£) | Notes |
|---|---|---|---|
| Loft insulation top-up (250mm) | 300 | 900 | Per house |
| Cavity wall insulation | 500 | 2,500 | Per house, blown-fill |
| Solid wall external insulation | 8,000 | 20,000 | Per house |
| Solid wall internal insulation | 3,500 | 12,000 | Per house |
| Floor insulation per m² | 40 | 90 | Add to slab or under floorboards |
| Radiator upgrade for ASHP | 1,500 | 5,000 | Larger radiators |
| ECO4 grant (eligible) | -1,000 | -15,000 | Means-tested |
| GBIS grant | -100 | -3,000 | Various measures |
How Long Does It Take?
Loft top-up: 1 day. Cavity wall: 1-2 days. Solid wall: 1-2 weeks. Heat pump install: 1-2 weeks (after insulation complete).
DIY or Professional?
Loft top-up DIY-able. Cavity wall, solid wall, radiator upgrade: professional only.
Choosing the Right Tradesperson
PCA or specialist insulation contractor. MCS-certified for heat pump install. Get EPC survey identifying priorities.
UK Regulations
Building Regs Part L (thermal). ECO4 means-tested grants. GBIS broader eligibility. BUS grant for heat pump requires acceptable insulation level (EPC).
Common Problems
- ASHP installed without insulation upgrade: Underperforms in poorly-insulated home. Cost of running unattainable.
- Cheap insulation: Inadequate fitting causes cold spots. Quality fitting essential.
- Vapour barriers missing: Solid wall internal insulation without VCL causes condensation.
- Grant eligibility wrong: Some grants means-tested. Check eligibility before committing budget.
Frequently Asked Questions
Insulation needed for ASHP?
EPC C or better. Poor insulation: ASHP underperforms. Best to upgrade insulation first, then install ASHP.
Best order: insulation then heat pump?
Yes — insulate first, then size and install heat pump for the now-insulated home. Right-sizing critical.
Cost vs gas boiler running?
Insulation upgrade £3,000-£15,000. Annual savings on gas alone £200-£800. Payback 10-15 years. Plus ASHP advantage.
Grants for insulation?
ECO4 (means-tested, generous), GBIS (broader eligibility). Check via energy supplier or Energy Saving Trust website.
Wall insulation external or internal?
External: more expensive (£8,000-£20,000), no internal space loss. Internal: cheaper (£3,500-£12,000), loses 80-150mm of room.
How much will I save on heating?
Quality insulation: 20-50% heating bill reduction. Combined with ASHP: further 30-50% saving.
This guide was written with AI assistance and is intended for general information only. Prices are estimates based on UK averages and may vary by region. Always get at least three quotes and consult a qualified professional before starting any work.
NEWAI Trade Assistant
Got more questions
about renewable energy?
Ask follow-ups in plain English. The AI explains options, sequencing and what to ask the renewable energy — so you walk in informed.
I'm planning a job. Should I be looking for a renewable energy?
Sounds like a job for renewable energy. Tell me what you're trying to do — I'll walk you through costs, timeline and what to ask before they start.
FREE QUOTES60 SECONDS
Keep reading
VIEW ALL RENEWABLE ENERGY GUIDES →More renewable energy guides.
Guide
Renewable Energy Repair Process
Investing in renewable energy is a significant commitment for any UK homeowner. Whether you have solar PV panels, a battery storage system, or an air source hea...
READ GUIDE →GuideSolar PV Installation Cost & Guide
Solar Photovoltaic (PV) systems are one of the most effective ways for UK homeowners to shield themselves from volatile energy prices. By converting sunlight di...
READ GUIDE →GuideSolar Panel Installation Guide
Solar panels are no longer a niche luxury; they are a core component of a modern, energy-efficient UK home. With energy prices remaining volatile, generating yo...
READ GUIDE →GuideBiomass Feasibility Assessment Guide
A biomass feasibility assessment is the essential first step for UK homeowners considering a switch from fossil fuels to renewable wood-based heating. This prof...
READ GUIDE →GuideRooftop Solar Installation Guide
Rooftop solar PV (photovoltaic) systems have become a staple of the UK's transition to green energy, offering homeowners a way to slash electricity bills and re...
READ GUIDE →GuideSolar Thermal Installation Process
Solar thermal systems are a highly efficient way for UK homeowners to reduce their carbon footprint and slash energy bills by harnessing free heat from the sun....
READ GUIDE →