This page explains double glazing cost in Merton Park, so you know what drives the price before we visit. It is for homeowners and landlords who want new windows or doors and need a clear guide to budget. You get starting prices for the main products, the things that push a price up or down, and how our written fixed quote works.
We fit uPVC, aluminium and timber-look windows and doors across Merton Park, and we price every job from a free survey. For the wider picture across the town, see our main double glazing prices guide, or go back to our Merton Park glazing page to see every service we offer here.
What affects glazing prices in Merton Park
Local homes shape local prices. Most of the houses we price here are Edwardian houses of the John Innes estate, Victorian villas and interwar semis, and the age and build of a home decide how much work sits around each frame.
- Postcodes we cover: SW19
We note access, parking and any upper-floor work on the survey, so the cost of getting frames and glass to your home is in the quote from the start.
Starting prices for windows and doors
The figures below are starting points, not quotes. Each one is for a standard size in a standard finish, supplied and fitted. Your price will depend on the size, the style, the glass and the work around the frame.
- uPVC casement window: from £400 fitted
- Sash window: from £650 fitted
- Composite front door: from £1,200 fitted
- Bifold doors: from £3,200 fitted
- Conservatory: from £8,500 fitted
- Skylight: from £750 fitted
We do not add a call-out charge for the survey. Once we have measured, you get a written, fixed quote with each frame listed. The price on that quote is the price you pay, unless you ask us to change the job.
How the style of window changes the price
The style you choose has the biggest effect on cost. Some frames use more profile, more hinges and more glass than others.
- Casement windows are the lowest cost style. They are quick to make and quick to fit, and they suit most houses built after the war.
- Sash windows cost more. A vertical slider has two moving sashes, balances in the frame and often a run-through horn or a deeper sill. Timber-look foils and heritage hardware add more.
- Bay windows need extra work. We may need to check the bay roof, fit a new bay pole or support, and join three or more frames at an angle.
- Tilt and turn windows sit in the middle. The hardware costs more than a casement, but the frame is simple.
If you live in an older house in Merton Park, the style that suits the front of the home may cost a little more. On the back of the house, a plain casement often gives the best value.
Doors, bifolds and larger openings
Door prices rise with width, weight and the number of moving parts. A single composite front door is the simplest job. It comes with a solid core, a multi-point lock and a choice of colours and glass.
Bifold doors cost more because each leaf runs on a track with rollers, hinges and seals. More leaves mean more parts. Aluminium frames cost more than uPVC, but they have slimmer sight lines and stay rigid over wide spans.
Large openings may also need building work. If you want to widen a gap for new doors, you will need a steel or concrete lintel and sign-off from building control. We price that work on its own line, so you can see it clearly.
Glass, frame colour and hardware
Once the style is set, the spec of each part adds to the cost. Here are the choices that make the most difference.
- Glass type: A-rated units with low-E coating and argon gas are standard. Triple glazing, acoustic glass and self-cleaning glass all cost more.
- Safety glass: Toughened or laminated glass is needed in doors, low panes and next to doors. It is a small cost per pane.
- Frame colour: White uPVC is the base price. Foils such as grey, black or woodgrain add cost, and a colour on both sides adds a little more.
- Bars and leaded designs: Georgian bars and leaded glass take more time to make and add to the price per pane.
- Locks and handles: We fit secure multi-point locks as standard. Upgraded handles, key-locking handles and anti-snap cylinders add a small amount.
Access, making good and other site costs
Two homes with the same windows can still have different prices. The work around the frame often explains the gap.
- Access: Upper-floor frames may need a tower or scaffold. Tight side paths or no parking near the home can add time.
- Removal: Taking out old timber or metal frames takes longer than old uPVC, and we dispose of them safely.
- Making good: We seal and trim inside and out. If the plaster or render is weak, we may need to repair it. We tell you on the survey if we think this is likely.
- Sills and boards: New sills and window boards are priced per frame.
- Number of frames: A whole-house job uses our team well, so the cost per frame can come down when we fit many at once.
Planning and Building Regulations
Most window and door swaps in Merton Park do not need planning permission. That changes if your home is listed, in a conservation area, or a flat. In those cases, the council may ask for a set style or material, and that can affect the cost.
All replacement windows must meet Building Regulations Part L for heat loss. The limit for a replacement window is a U-value of 1.4 W/m²K, or a Window Energy Rating of band B or better. We are FENSA registered, so we self-certify the work and send you the certificate. You do not need to pay a separate fee to Merton Council building control for a like-for-like swap.
How to compare quotes fairly
A low price is not always good value. When you compare quotes, check that each one covers the same things.
- Is the glass spec the same, with low-E coating, warm-edge spacers and argon fill?
- Is safety glass shown where the rules call for it?
- Are removal, disposal, sills and making good included?
- Is scaffold or a tower included if you need one?
- Is the installer registered with FENSA or Certass, or a like scheme?
- Is there an insurance-backed guarantee, and who provides it?
Our quotes list each of these points. Every job comes with a 10-year guarantee. Payment stages are set out in the written quote, so you know what is due and when.
From survey to fitting
We start with a free survey, then send a fixed quote. Once you agree, we make your frames to size and book a fitting date. You can read each step on our how we work page. When you are ready, ask for your free quote and we will arrange a visit in Merton Park.
We have been trading for many years, and we fit double glazing across Merton as well as here.
Frequently Asked Questions
Why can you not give an exact price over the phone?
Every opening is a little different. Sizes vary, walls may be out of square, and access changes from house to house. We need to measure each frame and check the brickwork, sills and render. After a free survey, we send a written, fixed quote. That way the price you agree is the price you pay, with no extras added on the day unless you change the job.
How long does double glazing take to fit?
Most homes take one to three days. A team can fit several casement windows in a day. Bays, sash windows and wide doors take longer because there is more work around each frame. We remove one frame at a time, so your home is never left open for long. We clear up each day and remove the old frames when we leave.
Do double glazed windows cut road noise?
Yes, new sealed units cut outside noise well compared with old single glazing or failed units. For a busy road, ask about acoustic laminated glass. It uses a special layer that blocks more sound. Mixing two glass thicknesses in the same unit also helps. Good seals around the frame matter as much as the glass, so the fit is key.
Does the guarantee cover frames and glass?
Yes. Our 10-year guarantee covers the frames, the sealed glass units, the hardware and the fitting. We give you the guarantee papers and your FENSA certificate after the job. Keep them safe, as you may need them when you sell your home.
Do you need planning permission to replace windows?
In most cases, no. Swapping windows for a like style counts as permitted development. You will need consent if the home is listed. You may also need it in a conservation area or for a flat, where the rules are tighter. We check this on the survey and tell you what applies. If consent is needed, we can supply drawings and product details.