What to look for when choosing a window fitter?

How to Find a Good Window Installer in Sussex

Interior view of cream woodgrain Residence 9 heritage windows

Choosing the right window installer can make all the difference to your home’s energy efficiency and long-term value as well as your peace of mind. The quality of the installation is just as important as the quality of the windows themselves. A poorly fitted window can lead to draughts, condensation, leaks, and long-term structural issues — which is why it’s worth knowing exactly what to look for before hiring a window company.

This article will give you a clear guide finding a reliable, professional window installer you can trust.


1. Check for Proper Accreditation

In the UK, competent installers should be registered with an approved body such as FENSA or CERTASS. This ensures the installation meets building regulations and includes a certificate for your records, important if you ever sell your home.

Any reputable installer in Sussex will be happy to show you their FENSA or CERTASS registration, insurance-backed guarantee and proof of public liability insurance. If an installer cannot provide these, consider it a red flag.


2. Look for Strong Local Reputation & Reviews

When searching for a window installer in Crowborough, Tunbridge Wells, Heathfield, Wadhurst, Crawley, or surrounding areas, your first stop should be online reviews.

The best places to check reviews are Checkatrade, Google and Facebook. Make sure to look at the quality of the feedback and what customers have to say about the company as well as the star rating. Good things to look for are mentions of clean workmanship, professionalism, clear communication, punctuality and aftercare. Installers with years of consistent positive reviews in your area are usually a safe bet.


3. Ask to See Real Examples of Their Work

Good window installers will happily provide photos and case studies of their work. High quality window installers also often have a showroom where you can browse and experience the various windows available to you before you buy.

It's good to notice if the company have experience working on only new builds, older properties or both?

If you have an older property in Sussex, it is important the window installers you choose are capable and experienced to work on such buildings as they often require:

Careful measuring, bespoke trims, specialist attention to draught-proofing and sensitivity to original features.

A portfolio shows how well the company handles different window styles, materials, and property types.


4. Compare Quotes — But Don’t Just Choose the Cheapest

It’s always smart to get 2–3 detailed quotes, but beware of prices that seem too good to be true. Low prices can often mean:

Cheap, low-performance windows, rushed installation, limited or no guarantee and hidden extras added later.

A good quote should clearly list:

  • Window specifications (e.g. uPVC, aluminium, timber)
  • Glass type & energy rating
  • Labour cost
  • Disposal of old windows
  • Timeframes
  • Warranty details

Transparency is a sign of professionalism.


5. Ask the Right Questions Before Hiring

Before committing to an installer, have you asked these questions…

1. Are you FENSA or CERTASS registered?
2. How long have you been installing windows in Sussex?
3. What brands or window systems do you use?
4. Do you use subcontractors or your own installation team?
5. How long is the product and installation guarantee?
6. Can you provide recent references from my local area?

A trustworthy installer will answer confidently and clearly with good evidence of their installations.


6. Check Communication & Professionalism

You can tell a lot about a company by your first interaction with them. A good installer will respond promptly, provide clear, honest advice, avoid pressure-selling tactics, respect your home and time and be approachable and patient with questions. Good communication before installation usually means good service during and after the job as well.


Conclusion

Finding a trustworthy, skilled window installer in Sussex doesn’t have to be difficult — it simply requires knowing what to look for. Check accreditations, read local reviews, compare detailed quotes, and choose a company with a proven track record in your local area.

A well-installed window won’t just make your home warmer and more efficient, it will last for decades.


PVCu timber look door in sussex

Case Study: New Windows & Doors for a Detached House

by S COTTINGHAM • 22 July 2025
Project Summary: Replacement of all old windows and doors for whole residential property. Key features of this project were: - New replacement 9 x PVCu windows to whole property - New replacement Front Door with single glazed panel - New replacement Back Door with double glazed panels Project Details: Insulation Services were appointed by clients after checking our reviews on Checkatrade and visiting our showrooms. Insulation Services visited the home to discuss options and designs for all windows and doors; timescales and budgets were also discussed. The bespoke quotation was prepared which included full details of the proposed products, the price, together with terms and conditions – all set out to fully inform the customer of everything involved. A set of pictures accompanied the quotation to illustrate each design style, layout and relative sizes. The work involved a series of 4 key stages: 1. Measuring and Pricing 2. Procurement and Planning 3. Risk Assessment and Method Statement 4. Installation The windows and doors products are all PVCu – selected for their style, performance and value for money. The front door is an ‘Assington’ style door featuring a high security locking system and an Irish Oak exterior and white interior, an obscure toughened glass sealed unit (to allow light into the hallway) and antique black door furniture. The windows are ‘A’ rated with 6 chambers for improved energy efficiency; they are internally glazed with argon filled 28 mm double glazed sealed units. We deployed a 2-man team to carry out the removal and installation work, liaising closely with the customer for the sequence of working (to cause least disruption and disturbance). All windows and doors were carefully and safely installed within one week on site. All waste materials were removed from site daily and the outside of the house was tidied up on completion. A follow up visit was arranged to address the last minor adjustments and to demonstrate how the windows opened for cleaning. Testimonial: “I am very happy with the new windows and doors; they make such a difference. The old windows had leaks and gaps and were very draughty! Now the newly installed windows are warmer and quieter – as well as looking good. I am happy to recommend Insulation Services.”