Written by Mark Reid,
Trades Editor ·Verified 23 September 2026
Gillingham's housing stock is a mixed bag, and that shapes what window installers actually deal with day to day. You've got Victorian terraces around Barnsole and Gillingham Green with original sash windows that need careful matching, post-war semis out towards Rainham and Twydall where uPVC replacements are the norm, and newer builds near Hempstead where double glazing is often already fairly modern but might need repair or upgrading to triple glazing. Coastal proximity to the Medway means salt air and damp can take a toll on frames faster than you'd expect further inland, so a lot of local jobs involve replacing rotten wooden frames or sorting out condensation between panes. Installers working across the Medway towns tend to know which streets have conservation restrictions too, which matters if you're near a listed building or in a conservation area where window style is controlled.
The businesses featured here come from public business listings, and we've ranked them using review rating and review count, with a small boost given to those showing a working website and phone number. We also check each business's homepage to confirm window installation is genuinely what they do day to day, which stops general builders or unrelated tradespeople sneaking onto a page like this. Listings flagged as permanently closed get removed automatically. Where you spot a Trust Verified badge, that business has gone further and passed our full verification, covering trade qualifications and accreditations, public liability insurance, trading history, customer review history, and registered company information. Our How We Verify page sets out exactly what that involves. For any business without the badge, those checks haven't been done by us, so it's worth doing your own homework before you commit to anything.
Before signing off on a quote, ask to see FENSA or CERTASS certification, since window replacements need to comply with Building Regulations and you'll want that paper trail if you ever sell the house. Check whether the price includes disposal of old frames, scaffolding if needed for upper floors, and making good the plaster or brickwork afterwards, as these get left off cheaper quotes and added on later. Ask about the warranty on both the frames and the installation labour separately, because they're often not the same length. Getting two or three quotes is worth the extra hour or two it takes, since prices for a full house of uPVC windows in Gillingham can vary by a thousand pounds or more between companies doing broadly the same job.
How We Select & Rate The Best Window Installers in Gillingham
Ranking is based on review rating and review count pulled from public business listings, with a small lift given to businesses showing a working website and phone number. We check each business's homepage to confirm window installation is their primary trade, which keeps unrelated businesses off the page. Listings marked permanently closed are removed automatically. Businesses carrying a Trust Verified badge have additionally passed our full verification, covering trade qualifications and accreditations, public liability insurance, trading history, customer review history, and registered company information. See our How We Verify page for the complete list. Other businesses shown haven't been independently verified by us, and their inclusion isn't an endorsement. Always carry out your own checks before hiring.
Recommended and Featured listings are paid placements, so a business's fee affects whether and where it appears. Every other listing is ranked on rating and review count from third-party business listings. How we rank & verify →
Window installation across Gillingham and the surrounding Kent area is the focus of D W C Home Improvements Ltd, a company operating under the ME7 postcode. The firm handles supply and fitting of windows for domestic properties, offering a local point of contact for homeowners in the Medway towns. Details on the full product range are available via their website at dwckent.co.uk.
Dial Glass works mainly on older Gillingham properties, fitting replacement windows into period frames that new-build glazing firms often avoid. The team also handles flats and small commercial units where access or listed-building rules complicate installation. Reviews, averaging 4.8 from 18 customers, tend to mention tidy finishing around original brickwork.
Salmon Windows Ltd installs replacement windows and doors for residential properties in Gillingham and the surrounding area. The company operates from ME5 9JW, keeping its focus on the local Medway market rather than spreading thin across the region. Straightforward pricing and a clear scope of work are the hallmarks of how it operates.
Transparency notice: Recommended and Featured listings are paid placements, so a business's fee affects whether and where it appears. All other listings are ranked by a combined score drawn from ratings and review counts published on third-party business listings, plus basic completeness signals such as a working website and phone. A Trust Verified badge means we have independently checked that business's documents; businesses without it have not been independently verified by us. How we verify →
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How much does a window installers cost in Gillingham?
For a standard uPVC casement window, you're typically looking at £350 to £650 per window supplied and fitted, depending on size and glazing spec. A full house replacement (say eight to ten windows on a three-bed semi) often lands somewhere between £4,000 and £8,000. Sash window replacements or timber frames cost more, often £700 upwards per window because of the extra labour and materials. Triple glazing and bay windows push the price up further. It's normal to get two or three quotes since prices vary a fair bit between installers for what's essentially the same spec.
How long does window installation take?
A single window replacement usually takes half a day to a full day, including removal of the old frame and fitting the new one. For a whole house, most installers can get through six to eight windows in a day if it's straightforward uPVC-to-uPVC work, but it can stretch to two or three days if there's brickwork repair, scaffolding for upstairs windows, or awkward access. Bay windows and anything requiring structural work will always take longer, so ask for a realistic timeframe upfront rather than assuming it's a one-day job.
Do I need planning permission for new windows in Gillingham?
Most window replacements fall under permitted development and don't need planning permission, but there are exceptions. If your property is in a conservation area (parts of Gillingham near the Great Lines and the historic dockyard fall into this category) or it's a listed building, you'll likely need consent before changing window style or materials. Medway Council's planning department can confirm this for your specific address, and any decent installer working locally should already know which streets have restrictions.
What's the difference between FENSA and CERTASS certification?
Both are competent person schemes that let installers self-certify their work meets Building Regulations, so you don't need a separate council inspection. FENSA is the older and more widely recognised scheme, CERTASS covers similar ground. Either is acceptable, but make sure your installer is registered with one of them and that you get a certificate after the job, because you'll need it as proof of compliance if you sell the property later.
Should I choose uPVC, aluminium, or timber windows?
uPVC is the most common choice for Gillingham's semis and terraces because it's low maintenance and reasonably priced, typically £350 to £650 per window. Aluminium suits more modern or larger properties and handles bigger panes well, but costs more, often 20 to 30 percent above uPVC. Timber suits period properties, especially Victorian terraces where sash windows are original, but needs more upkeep and costs the most upfront, often £700 to £1,200 per window. Think about maintenance time and how the property looks from the street before deciding.
What should I check before booking a window installer?
Ask to see their FENSA or CERTASS registration number and check it directly on the relevant scheme's website rather than just taking their word for it. Ask for proof of public liability insurance and check how long they've been trading, since a company that's only a year old carries more risk if something goes wrong later. Read through recent customer reviews on public listings, not just the ones featured on a company's own website. Get the quote in writing with a clear breakdown of materials, labour, disposal, and any making-good work, and always get at least two comparison quotes before signing anything.
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