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Home energy upgrades

Solid wall insulation — internal and external

For solid-walled homes, the single biggest saving you can make — often fully grant-funded.

Book Your Free Solid wall insulation SurveyCall Us Free: 0800 229 4094

No cost. No obligation. No pressure.

MCS-certified installer
TrustMark approved
PAS 2035 compliant
ECO4 approved installer
OMEGA solid wall insulation install

Installed by OMEGA's own teams across Essex, Suffolk, Kent and Cambridgeshire.

Proof, not promises

Why homeowners pick OMEGA for solid wall insulation.

4.9

340+ verified reviews across Google, Checkatrade and TrustPilot

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    Homes upgraded

    Across Essex, Suffolk, Kent and Cambridgeshire since 2018

  • 0 yr

    Product guarantee

    Insurance-backed through CIGA, SWIGA and manufacturer cover

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    Quote turnaround

    Written, fixed-price, line-by-line. No pressure, no chasing

The surveyor spent an hour walking us through the whole house, wrote a plan at the kitchen table, and the grant side of it was sorted by them, not by me. Five months in, the bills are down by almost exactly what they said.

JRJulie R. — verified Chelmsford customer, cavity wall + loft top-up, February 2026

0–3 days per room

Install time (IWI)

0–14 days

Install time (EWI)

£0+

Typical annual saving

0 years (CIGA/SWIGA)

Product guarantee

PAS0 · TrustMark · SWIGA

Accreditation

About this service

Solid wall insulation, designed properly.

Roughly one in five UK homes has solid walls, most of them built before 1930, and they lose heat at almost twice the rate of a modern cavity. It's why older terraces and detached pre-war houses feel so expensive to heat — the fabric isn't really trying. The fix is either internal wall insulation (IWI), fitted from the inside and skimmed like a normal wall, or external wall insulation (EWI), which wraps the outside of the house in rigid insulation and weather-tight render. Both are PAS2030-accredited, both typically save £640 or more a year on a detached solid-wall property, and for eligible households both can be fully funded through ECO4 or the Great British Insulation Scheme. We price both on the survey so you can see the trade-offs with your house in front of you.

What you get

  • Cuts heating demand by up to 40% on a solid-walled pre-war home — genuinely felt in week one
  • Typical saving of £640+/yr on a detached solid-wall property, more on larger exposed sites
  • Eliminates cold wall surfaces and the condensation mould that collects in corners and on chimney breasts
  • Fully funded installs routinely available through ECO4 and the Great British Insulation Scheme
  • 25-year insurance-backed product guarantee (CIGA/SWIGA) plus OMEGA's 5-year installation cover

See the numbers

What solid wall insulation actually costs — and saves

Live tool, Q2 2026 prices. Slide through property size for an honest instant estimate — your real quote will come in writing within 48 hours of a free survey.

The OMEGA difference

Eight things we do that most solid wall insulation installers don't.

Not brand chest-beating. Each of these is something you can phone up and check — written down on every quote, baked into every install.

OMEGA
A typical installer

  • Who turns up on install day

    Our own PAS2030-accredited engineers, directly employed

    Subcontracted day-labour, often met for the first time that morning

  • How the quote is built

    Written line-by-line inside 48 hours, each measure costed and justified

    Pressure-priced on the day with artificial "sign now" discounts

  • Grant and funding paperwork

    ECO4 · GBIS · BUS · HUG2 checked on the first visit, filed by our team

    You chase the forms, or pay full price because nobody looked

  • Survey depth

    Room-by-room heat-loss calc, ventilation check, thermal imaging where it helps

    A 15-minute look round and a best-guess sizing from the EPC

  • Product spec

    BBA-certified materials named on the quote — the installer signs each layer off

    "Generic equivalent" materials chosen for margin, not performance

  • Guarantees you can actually claim on

    25-year insurance-backed product cover plus our own 5-year workmanship guarantee

    1-year workmanship only, manufacturer cover voided by install errors

  • Aftercare once the van drives off

    Same office you called first day. Issues phoned in and fixed, not forwarded

    A different number every time, with "that is out of warranty" as the default reply

  • Honesty when a measure isn't right for your home

    We'll tell you to insulate first, or wait a year — and quote that instead

    Sells the measure that pays the commission, regardless of fit

Ask any OMEGA surveyor to walk through this list at your first visit — if we don't match every row, don't hire us.

Accreditations that matter

Not logos. The certifications solid wall insulation actually needs.

Every one of these is checkable online. Every one changes something concrete about the job — the survey, the materials, the guarantees, the way the grants land.

  • PAS 2030

    Install quality standard for retrofit measures

    Our teams are certified to the installation standard that grant-funded work is audited against.

  • PAS 2035

    Whole-house retrofit co-ordination standard

    We sequence fabric-first so measures don't undermine each other — the same discipline ECO4 requires.

  • TrustMark

    The only endorsement scheme backed by the UK consumer body

    Every install is lodged on the TrustMark register so your cover travels with the property.

  • CIGA / SWIGA

    25-year insurance-backed cavity + solid-wall guarantee

    If OMEGA is no longer trading in 2049, your guarantee still pays out. Insurance-backed, not hope-backed.

How it works

Four steps from survey to handover.

  1. 01

    Fabric-first survey

    Full heat-loss check, ventilation assessment and — on every grant-funded job — a PAS2035 retrofit designer review. You leave with a written rationale before committing.

  2. 02

    IWI vs EWI on one quote

    Where both are feasible, we price both. Listed buildings and small terraces usually favour IWI; detached homes usually favour EWI. Your surveyor walks you through the trade-offs.

  3. 03

    Install

    IWI runs 2–3 days per room, one room at a time, so you're never without somewhere warm. EWI runs 7–14 days with scaffold, full weather protection and daily photographs.

  4. 04

    Certification and aftercare

    TrustMark certificate, 25-year CIGA/SWIGA product cover, and a courtesy aftercare call six and twelve months after install to check everything's performing.

Want a 2-minute answer first?

Not ready to book a full survey?

Tell us a bit about your place and we’ll come back with specific numbers for your home — no slot to pick, no pressure.

Prefer to talk now? Call free on 0800 229 4094.

Quick enquiry — Solid wall insulation

No full-form-fill, no credit check, no follow-up spam. One call to explain what's possible and what it would cost.

No cost. No obligation. No pressure.

What most customers ask first

The honest worries about solid wall insulation — named and handled.

Every homeowner brings two or three silent worries to the first survey. Here's what they are and how we handle them — no salesy dodges.

  • The worry

    Will I lose a lot of room size with IWI?

    How we handle it

    Between 80 and 100mm off each internal wall. That sounds a lot but in practice it barely changes the feel of the room — most customers notice the warmth before they notice the wall moving.

  • The worry

    Can I keep my external brickwork looking the same?

    How we handle it

    Yes — on IWI the outside doesn't change at all. On EWI we can render to match the original, or specify transparent ProPERLA where planners or listing restrictions require the brick to stay visible.

  • The worry

    What about interstitial condensation?

    How we handle it

    Every grant-funded solid-wall job is sequenced by a PAS2035 retrofit designer — which means the vapour strategy is modelled, not guessed. We fit the ventilation upgrades on the same mobilisation and guarantee the outcome for five years.

  • The worry

    Will the grant really cover the full cost?

    How we handle it

    On ECO4, most eligible households pay nothing. A typical EWI install is £12,000–£18,000 and ECO4 regularly covers it in full when it's bundled with another measure. We run the eligibility check for you — you never see a form.

Proof in the data

Why solid wall insulation pays for itself

Cumulative £ saved vs install cost for your property type. Drag the chart to scrub through the years.

Live · grant eligibility check

What grants are likely on your solid wall insulation?

Type your postcode. We'll show which schemes are likely to apply for your property and this measure. The exact eligibility check happens on your free survey — this is the indicator that gets you 80% of the way there.

Heuristic indicator only — the survey is where actual eligibility is decided. Free, no obligation, takes 45 minutes.

Schemes covered · ECO4 · GBIS · BUS · HUG2 · SEG · OZEV · 0% VAT

Grants and funding

Funding you may be eligible for.

Eligibility changes often. Our surveyor checks every active scheme for your home as part of the free survey, and handles the paperwork end-to-end if you qualify.

See all grants and funding →

  • ECO4 — up to 100% of install cost for eligible households, one of the UK's most generous schemes

  • Great British Insulation Scheme (GBIS) — top-up funding for EPC D and below solid-wall homes

  • Home Upgrade Grant 2 (HUG2) — for off-gas-grid solid-wall properties that don't qualify for ECO4

Common questions

Solid wall insulation — answered honestly.

Should I go internal or external wall insulation?

External (EWI) gives the biggest performance lift, doesn't shrink any room and resets the whole look of the outside — but it costs more and needs planning consent in conservation areas. Internal (IWI) is faster, cheaper and keeps your external brick on view, but it takes 80–100mm off each wall. Our surveyor walks both options at your kitchen table with your specific rooms in mind — no pressure either way.

Will solid wall insulation cause damp?

Only when it is rushed or ventilation is ignored — and that's exactly where most cowboy jobs fail. Every OMEGA solid-wall install includes a proper ventilation assessment, trickle-vent uprating where needed, and in some homes a small decentralised MVHR. We guarantee against condensation damage for five years in writing — if anything appears, we come back out.

Do I need planning permission?

Internal wall insulation never needs planning. External is permitted development on most detached and semi-detached homes; listed buildings, conservation areas and Article 4 streets do need consent. We handle the planning application as part of our service so nothing lands on you.

Can the grants really pay for all of it?

Yes — on ECO4, most eligible households pay nothing at all. A typical solid-wall EWI install runs £12,000–£18,000, and ECO4 regularly covers it in full when it's packaged with another measure like a loft top-up or heating control upgrade. Our surveyor runs the eligibility check for you on the first visit — you never see a form.

Real installs

Solid wall insulation projects we've delivered

All case studies →
Cambridge

Solid wall internal insulation + multifoil room-in-roof on a Cambridge Victorian

Sympathetic IWI on the front rooms, multifoil to the room-in-roof loft conversion. EPC E → C, £1,120/yr saved, ECO4 + LA Flex stacked.

  • +22 points
  • £1,120/yr saved
Read the story →

Where we install

Solid wall insulation across Essex, Suffolk, Kent and Cambridgeshire.

We install solid wall insulation in every one of our covered counties. Each local team knows the housing stock, the grant routes, and the council-specific flex schemes that apply.

Often paired with…

Ready to start?

Free 45-minute home energy survey. Written quote within 24 hours. Zero pressure.

Book Your Free Solid wall insulation SurveyCall Us Free: 0800 229 4094

No cost. No obligation. No pressure.

25-year product guarantee. 5-year installation guarantee. If anything isn't right, we fix it free.

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