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Home energy upgrades

Cavity Wall Insulation

Cavity wall insulation injected through small drill holes — no disruption, no mess, completed in a day. TrustMark and CIGA guaranteed for 25 years.

Book Your Free Cavity SurveyCall Us Free: 0800 229 4094

No cost. No obligation. No pressure.

MCS-certified installer
TrustMark approved
PAS 2035 compliant
ECO4 approved installer
OMEGA cavity install

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

Proof, not promises

Why homeowners pick OMEGA for cavity.

4.9

340+ verified reviews across Google, Checkatrade and TrustPilot

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    Homes upgraded

    Across Essex, Suffolk, Kent and Cambridgeshire since 2018

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    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–£600

Typical cost

£0

Annual saving

0–2 years

Payback period

About this service

Cavity, designed properly.

Fill the gap in your walls and cut heat loss by up to 35%. Installed through small drill holes with minimal disruption.

What you get

    See the numbers

    What cavity 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 cavity 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 cavity 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.

    • 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.

    • PAS 2030

      Install quality standard for retrofit measures

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

    • MCS

      Microgeneration Certification — solar, heat pumps, batteries

      Without MCS you can't claim the Smart Export Guarantee, the BUS grant, or 0% VAT. We're fully certified.

    • BBA certified

      British Board of Agrément product certification

      Every insulation layer we install is named on the quote and BBA-certified — no unlisted substitutes.

    How it works

    Four steps from survey to handover.

    1. 01

      Free Home Energy Survey

      We inspect your walls with a borescope to confirm cavity width and suitability. We also check for damp and ventilation.

    2. 02

      Grant Application

      We submit your application to ECO4 or GBIS. Most cavity wall insulation is fully funded for eligible homeowners.

    3. 03

      Drill, Inject, Seal

      Small 22mm holes are drilled in the mortar joints, insulation is injected under pressure, and holes are sealed to match your brickwork.

    4. 04

      CIGA Guarantee

      You receive a 25-year CIGA guarantee, a completion certificate, and a lodged TrustMark warranty.

    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 — Cavity

    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 cavity — 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

      Is this going to feel like a sales pitch?

      How we handle it

      No. The survey is a 45-minute look round with a written plan at the end — we leave without asking you to sign anything. Nearly a third of our surveyed customers go with us later, not the same day.

    • The worry

      What if I don't qualify for the grants?

      How we handle it

      You still get the same fixed-price, line-by-line quote and the same 25-year product cover. We publish the self-funded payback next to the funded one so you know either number before you commit.

    • The worry

      How disruptive is the install?

      How we handle it

      Most of our measures are single-day from outside or from one room at a time. Dust sheets down, vacuumed up behind us, photos of every stage. You can work from home through nearly all of it.

    • The worry

      What if something goes wrong later?

      How we handle it

      One phone number — 0800 229 4094 — and the same team comes back out. 25-year product guarantee, 5-year workmanship cover. If it breaks, we fix it free. That's the deal.

    Proof in the data

    Why cavity 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 cavity?

    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

    Common questions

    Cavity — answered honestly.

    How do I know if my walls are cavity?

    If your home was built between 1930 and 1995, it almost certainly has cavity walls. Our surveyor confirms this with a borescope inspection during your free survey.

    Will cavity wall insulation cause damp?

    No — when installed correctly by certified professionals, cavity wall insulation actually reduces damp by keeping internal walls warmer. We carry out a full damp check before installation.

    How long does the installation take?

    Most homes are completed in 2–4 hours. The drill holes are small (22mm) and are sealed to match your brickwork colour.

    What guarantee do I get?

    Every cavity wall insulation installation comes with a 25-year CIGA guarantee, backed by an independent body. This transfers to new owners if you sell your home.

    Is cavity wall insulation free?

    For many homeowners, yes. ECO4 and GBIS fund cavity wall insulation for eligible households. We check your eligibility during the free survey and handle all the paperwork.

    Where we install

    Cavity across Essex, Suffolk, Kent and Cambridgeshire.

    We install cavity 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 Cavity 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.

    Call FreeBook Your Free Home Energy Survey