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‘Mind the Gap’ Why Choosing the Right Window Installer is Everything
‘Mind the Gap’ Why Choosing the Right Window Installer is Everything
Category: Advice & Guidance
Reading Time: 6 Minutes
📌 The 30-Second Summary
- Research is Vital: Don’t just trust a flyer. Check specific reviews on Checkatrade and Which? Trusted Traders.
- Visit a Showroom: If they don’t have a physical address you can visit, where will you go if something goes wrong?
- Watch for “Sales Pressure”: If a company forces you to sign “today” for a discount, walk away.
- Check the Guarantee: Ensure it is an Insurance Backed Guarantee (IBG) for at least 10 years.
Buying double glazing is one of the biggest investments you will make in your home. It can feel overwhelming, and the industry unfortunately still has a reputation for pushy sales tactics and “here today, gone tomorrow” cowboy builders.
But it doesn’t have to be that way. By asking the right questions, you can filter out the bad apples and find a partner who cares about your home as much as you do.
Table of Contents
1. The “Digital Detective” Phase
A recommendation from a friend is a great start, but it isn’t enough. You need to verify the company’s track record over time.
Don’t just look at the star rating; read how the company responds to reviews. Do they own their mistakes? Do they solve problems?
| Where to Check | What to Look For |
|---|---|
| Checkatrade | Look for consistency over years, not just a burst of recent reviews. |
| Which? Trusted Traders | This is harder to get into than other schemes. It involves strict code-of-conduct checks. |
| Companies House | Check how long they have been trading. A 10-year guarantee from a company that opened last year is risky. (KJM has traded since 1983). |
2. The Showroom Test
A “Man in a Van” might be cheaper, but does he have a physical address? If a company has invested in a showroom, it shows they are established, financially stable, and accountable.
Visiting a showroom (like ours in Andover) allows you to:
- Touch the Product: See the quality of the welds and the clarity of the glass.
- Compare Colours: “Anthracite Grey” looks different on a screen than in daylight.
- Meet the Team: Are they helpful advisors, or pushy salespeople?
3. The Sales Pitch (Red Flags)
This is the biggest complaint in our industry. You invite someone round for a quote, and they won’t leave your house until you sign.
⚠️ The “Sign Today” Scam
If a salesperson says: “I can call my manager to get a special discount, but only if you sign right now,” this is a manipulation tactic.
A reputable company will give you their best price upfront and leave you with a written quote to think about in peace.
At KJM, we have a strict No Pressure Promise. We provide the quote, and we let you decide. No hard sell, ever.
4. Energy Ratings & Specs
Not all “white plastic windows” are the same. When comparing quotes, you must compare the specification.
Does the cheaper quote include:
- A-Rated Efficiency? Verified by the BFRC.
- Argon Gas? Essential for insulation.
- Warm Edge Spacers? To prevent condensation.
- Security? Are they PAS24 certified with multi-point locks?
5. Who is Installing?
You might buy from a great salesman, but who is turning up to cut holes in your house?
Some national companies sub-contract everything to the lowest bidder. This means the team turning up might have never worked for the company before. You want a company that uses dedicated, regular installation teams who know the products inside out and are accountable for their work.
6. KJM Group’s 5-Point Quality Installer Checklist
| Requirement | Why It Matters |
|---|---|
| Accreditation (e.g., FENSA/GGF) | Ensures the installer meets current building regulations (like Document L) and can self-certify compliance, saving you a hassle. |
| Own Employed Fitting Teams | Subcontracted labour can lead to inconsistent quality. Employed, dedicated teams are invested in the company’s reputation. |
| No Pressure Sales Policy | Indicates an ethical business model focused on customer needs rather than chasing immediate, high-margin sales. |
| Long-Term Credentials (Which?) | Independent endorsement from bodies like Which? Trusted Trader proves a sustained track record of quality and customer satisfaction. |
| Comprehensive Warranty | Look for a warranty that covers both the product and the installation work for maximum peace of mind. |
7. Frequently Asked Questions
FENSA is a government-authorised scheme. A FENSA certificate proves your installation complies with Building Regulations. Without it, you may face legal issues when you try to sell your home.
Yes. Even the best installations can have minor settling issues. A reputable installer will always return to adjust hinges or seals after the installation to ensure you are 100% happy.
It should cover the frames (discolouration), the glass (seal failure/misting), and the moving hardware (handles/hinges). Always ask to see the warranty terms in writing before you buy.
Mark Pearce is a highly experienced specialist in the double glazing industry, having built his knowledge from the ground up through hands-on experience in installation, manufacturing, sales, and business management. Beyond his role at KJM, Mark is a keen blogger, writer, and traveller, often sharing insights on the latest innovations in the home improvement industry.
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