How to Choose an Insulation Installer: PAS 2030, TrustMark and IBGs Decoded

Decoding the badges

PAS 2030-19

PAS 2030 is the British standard for installing energy-efficiency measures, and the -19 edition is the current framework for this work. Certification means an independent body has audited the company’s installation processes, staff competence, quality management and paperwork — and keeps auditing them to stay certified. For private work it is voluntary, which is what makes it meaningful: a firm that carries PAS 2030-19 chose to be audited when nothing forced it to. Ask which certification body issued it and check the certificate is current.

TrustMark

TrustMark is the government-endorsed quality scheme covering work in and around the home. A registered business has been vetted, is monitored, and signs up to a code of conduct with dispute-resolution behind it. The practical point: registration comes with a licence number, and the public register lets you check it. Any firm displaying the logo without a number you can verify is asking you to trust a JPEG. Ours is 2259022 — look it up.

Manufacturer approvals

EWI and IWI are systems, not piles of material — board, adhesive, mesh, basecoat and finish designed and warranted together. System manufacturers train and approve installers, and the approval matters twice: it means the installer has been taught to install that system to specification, and it means the manufacturer’s warranty will actually stand behind the finished wall. Ask which system is being quoted — by name, not “insulated render” — and confirm the installer is approved for it. We install systems from Licata, SWIP, Kingspan, ROCKWOOL, STEICO, Celotex and EPS-based build-ups, and the system name appears on the quote every time.

Insurance, and who actually does the work

Two unglamorous questions that matter more than any logo:

• “What’s your public liability cover?” Wall insulation means scaffolding over pavements, render systems on party boundaries and heavy materials at height. £5m public liability is the level we carry and the level we’d suggest you expect for this class of work. Ask to see the certificate — a professional outfit has it to hand and is never offended by the question.
• “Who will be on my scaffold?” Many insulation brands are sales offices that subcontract installation to whichever gang is free. That model can work, but it splits accountability between the name on your contract and the people on your wall. We run our own in-house team with no subcontractors — the surveyor who prices your job and the crew who install it answer to the same company. Whoever you use, get the answer in writing.

Warranty vs IBG — the difference that bites

This is the section worth reading twice, because the two documents sound interchangeable and are not:

• A manufacturer warranty — typically 10 years on the systems we install — covers the products in the system, provided it was installed to the manufacturer’s specification. If the installer botched the job, the manufacturer can decline; if the installer has disappeared, the workmanship side of your protection went with them.
• An insurance-backed guarantee (IBG) — ours runs 25 years — is an insurance policy that stands behind the installer’s workmanship guarantee. If the company that installed your walls ceases trading in year 12 and the render fails in year 14, the IBG is what responds. Given how many insulation firms have come and gone over the years, the IBG is arguably the single most important document on the quote.

Ask three things: how long, who underwrites it, and whether it is included in the quoted price or an extra. Then ask for it in writing — a guarantee described verbally on a doorstep has a value of exactly nothing.

Questions to ask every installer

1. Which named system are you quoting, at what board thickness? Vague answers here predict vague walls.
2. Are you PAS 2030-19 certified and TrustMark registered — and what are the numbers? Then verify both yourself.
3. Who physically does the installation — employees or subcontractors?
4. What insurance do you carry, and can I see the certificate?
5. What guarantee comes with the job — manufacturer warranty, workmanship, IBG — for how long, and underwritten by whom?
6. Is the quote fixed and itemised — scaffold, reveals, sills, gutters, making good?
7. How will you detail my window reveals? A specific answer (reveal boards, trims, extended sills) marks a real installer — it is the fiddly junction where cheap jobs cut corners, as our cold bridging guide explains.
8. Can I see recent local jobs and verified reviews?

None of these questions offends a good installer. Several of them visibly annoy a bad one, which is useful information in itself.

Red flags

• Pressure sales. “This price is only valid today” is not how surveyed, engineered work is priced. A genuine quote survives a fortnight of thinking time.
• No itemised quote. One headline number hides what is and isn’t included — and the gap surfaces later as extras.
• No scaffold line on an EWI quote. The fastest tell in the trade. External wall insulation needs scaffolding; it appears on 88 of our real quotes as its own line. A whole-house EWI price with no scaffold either hides it in the number, plans to charge it later, or plans to work unsafely. Every answer is disqualifying.
• No named system. “Insulation and render” without a manufacturer means no system warranty worth the name.
• Price without a survey. Nobody can price wall insulation honestly from the kerb — condition, access and detailing drive the cost.
• Badges that can’t be verified. Logos without licence or certificate numbers, or numbers that don’t check out on the public registers.

A worked example: running the checklist on us

Rather than tell you we’re trustworthy, here is our own entry for every line above, so you can see what a complete answer looks like — and check it independently:

The last row is the one we’re proudest of: we publish real prices from our won and installed jobs so you can sanity-check anyone’s quote — including ours — against what this work actually costs. Background on typical figures is in the insulation cost guide, and the services themselves are detailed on the EWI and IWI pages.

The honest caveat to end on: credentials are a filter, not a guarantee. Paperwork proves a company can work to standard, not that it will on your house on a wet Tuesday — which is why the reviews, the published jobs and the itemised quote matter as much as the certificates. Run the checklist on everyone, us included, then get a free, fixed, itemised quote and compare like with like.

Choosing an installer FAQs