Why This Industry Has a Bad Reputation - And Why It Doesn't Have To
The UK glazing sector has two halves. The first is full of small family firms who fit good glass at fair prices and live or die by word of mouth. The second is dominated by high-pressure national sales operations that exist to upsell £600 jobs to £6,000. Searching "double glazing repair near me" returns both, ranked by ad spend rather than honesty.
This is the guide we wish every customer had read before calling around. None of it is industry secrets - just 30 years of seeing how the good firms behave and how the bad ones don't.
7 Red Flags That Should End the Call
- "Today only" pricing. A real fitted price for a real piece of glass does not vanish at midnight. If a sales rep tells you the £6,000 quote drops to £3,000 if you sign tonight, the genuine price was always £3,000 - or lower.
- Refusing to leave a written quote. Any reputable firm leaves the price in writing, with VAT broken out and each window itemised. "We'll send it later" usually means "we'll call you back to renegotiate."
- Demanding a large deposit upfront. For repair jobs under £2,000, no deposit should be needed. For larger jobs, a 10-25% deposit on the day of fitting is normal. 50% upfront is not.
- Quoting full replacement when only the glass has failed. A misty unit is a £100-£180 sealed-unit swap, not a £600+ full-window job. A repairer pushing replacement on sound frames is selling, not fixing.
- No physical address. Mobile number only, no van livery, no workshop address, no Companies House record. If the 25-year guarantee paper exists at all, it'll be from a shell company that dissolves the day they need to honour it.
- Pressure to sign before the survey. Anything booked over the phone without a measure-up is a guess at best and a hook at worst.
- Telling you the FENSA certificate "doesn't matter for repairs". Strictly correct for sealed unit swaps, which don't need FENSA. But it's a useful tell - good firms explain that clearly; bad firms use the technicality to dodge any kind of accreditation.
9 Questions to Ask Every Repairer Before You Book
- How long have you been trading at the same address?
- Are you a member of FENSA, Certass, Which? Trusted Trader, or TrustMark?
- Will you provide a written, itemised quote with VAT separated?
- Is the 25-year guarantee manufacturer-backed and transferable on house sale?
- Are your sealed units argon-filled and Low-E coated as standard, not as an upgrade?
- What warm-edge spacer do you use - Swisspacer, Super Spacer, Thermix?
- Will you fit toughened glass where Building Regs require it - included in the price?
- Do you ask for a deposit, and if so how much and when?
- Can I see three local reviews on Google or Trustpilot from the last 6 months?
You don't need perfect answers on all nine. You do need clear, unhesitant ones. Hesitation, sales-script deflection or "let me check with the office" on basic factual questions is a tell.
What a Fair, Honest Quote Actually Looks Like
- Per-window pricing - never a single mystery total
- Glass specification in plain English (4mm clear / 20mm argon / 4mm Low-E, warm-edge spacer)
- Toughened or laminated upgrades clearly priced and flagged where regs require them
- Fitting, removal, waste disposal and silicone all included
- Estimated lead time and fitting date
- Written 25-year guarantee terms with the manufacturer named
- Company name, address, VAT number, Companies House number and FENSA / Certass / TrustMark number where applicable
If any of those are missing, ask for them. A firm worth hiring will add them without complaint.
The "Three Quotes" Rule (And How to Do It Properly)
Always get three quotes. But the value isn't in finding the cheapest - it's in spotting the outliers. If two independents quote £1,200 for the same job and a third quotes £4,500, the third isn't doing the same job; they're including overheads, finance commissions or unnecessary upsells. Equally, if a quote comes in at half the others, the spec is almost certainly cheaper glass or an uninsured fitter.
Compare like-for-like on these three things and only these three: glass specification, written guarantee, and total fitted price. Everything else is noise.
Local Independent vs National Chain - The Honest Trade-Off
| Factor | Local independent | National chain |
|---|---|---|
| Typical price | £90-£180 per sealed unit | £300-£800 per sealed unit |
| Quote speed | Same day or next day | 3-7 day appointment with sales rep |
| Survey style | Glazier measures and quotes | Salesperson with iPad, no glass tools |
| Guarantee | 25 years manufacturer-backed | 10-25 years company-backed |
| Survives 10 years? | Most family firms do | Many chains have rebranded once or twice |
The honest case for a national chain is finance. If you need to spread a large bill over 5 years, the independents usually can't help. For everything else - speed, price, honesty, accountability - a local family firm wins.
Spotting the Upsell Mid-Quote
Watch for these conversation moves during the in-home survey:
- "While we're here, the frames are looking a bit tired..." (no, they're not)
- "This handle's on its way out, we'd usually replace all of them..." (£40 part, not a £400 job)
- "You're really better off doing the whole house for proper energy savings..." (the saving is in the failed units only)
- "This finance offer only runs to end of the month..." (it runs all year)
Polite, firm answer: "Thanks - I'm only looking at the misty units today." A good firm respects that. A bad firm escalates.
How We Do It at ClearPane
We've traded under the same name from the same Essex base for 30+ years. We quote per window, in writing, with the glass spec in plain English and a 25-year manufacturer-backed guarantee. We don't take deposits on jobs under £2,000. We don't sell windows you don't need. And if your frame is sound, we'll tell you so - and quote you the £100 sealed unit instead of the £800 replacement.
If you're across our Essex and East London service area, our instant quote calculator gives you a fixed price in 60 seconds with no salesperson required.