Misted or blown double glazing replaced
Misted, foggy or blown sealed units replaced from £185 a unit, fitted. Price yours online in about a minute.
Mist or droplets between the panes mean the seal has failed. We replace the sealed unit, not the window. Enter your sizes, choose your glass and see your price, with no obligation.
Step 1 of 6
Where is the glass going?
Choose where the glass is, so we can offer the right glass.
Bifold or sliding patio door glass? We price those from photos: bifold door glass from £510, sliding patio door glass from £765.
Step 2 of 6
What colour is your spacer bar?
The spacer bar is the strip you can see between the two panes, around the edge of the glass. It's usually silver, black or grey. We match it so the new unit looks like the others.
Warm edge spacers lose less heat at the edge of the glass.
Step 3 of 6
What size is your glass?
Enter the measurements in centimetres.
Your glass preview
📏 How to measure your glass
Only measure the glass you can see, from the frame or beads on one side to the other. To the nearest centimetre is fine: we measure properly at the visit.
Step 4 of 6
What type of glass?
Choose the glass that's right for the place it's going.
Your glass preview
Choose your pattern:
Patterns from the Pilkington Texture Glass range, plus frosted (satin) glass. We confirm your pattern at the measuring visit.
🛡️ Safety glass needed
Building regulations say glass in doors must be safety glass, so we've switched off the glass that isn't.
Step 5 of 6
Add Georgian bars or leading?
Choose Georgian bars or leaded glass for a traditional look.
Choose lead pattern:
Choose lead colour:
Your glass preview
🏠 Inside view
🌳 Outside view
Bar colours and widths depend on our glass supplier. We confirm them at the measuring visit.
Step 6 of 6
Your estimate
Check your glass units below, then add your details to see your price.
⚠️ This is an estimate. We confirm your price at the measuring visit, before we order anything.
- ℹ️ Prices are worked out from your sizes and choices, using our London prices. They include VAT, supply and fitting, and 3 or more units in one visit are 20% off. The measuring visit is free.
- ℹ️ Every unit is priced with Low-E glass and argon gas between the panes.
- 📞 Laminated glass, cut-outs and other extras: ask us for a price.
Add your details to see your price
We'll keep a copy of your estimate and get in touch to arrange the measuring visit.
Thanks. Here's your estimate.
We've got your details and we'll be in touch to arrange the measuring visit. To speed things up, send us photos of the windows on WhatsApp.
We couldn't send your details just now. To make sure we get them, please send this estimate to us on WhatsApp, or call us on 07946 160555.
You've changed your estimate since you sent it.
Estimates include VAT, supply and fitting. Every price is confirmed at the measuring visit, before we order anything.
Rather not measure? WhatsApp us a photo instead
See the difference
Before and after, from a job by our sister company, Dr Glass, outside London.
Why double glazing mists
A double-glazed unit is two panes of glass sealed together around the edge, with dry air or gas between them. Over the years the seal can fail. Damp air gets in, and you see mist, droplets or a white film between the panes that you can't wipe away.
Once that happens the unit has failed. It won't clear for good, and it keeps the heat in less well.
The fix: a new sealed unit
We take out the failed unit and fit a new one in the same frame. Your window stays as it is: same frame, same hinges, same handles. It's quicker and much cheaper than a new window.
Save 20% on 3 or more units in one visit, so if several windows have misted, it's worth doing them together.
Our 4-step replacement process
- 1
Price it
Use the price estimate above, or send us photos on WhatsApp.
- 2
We measure
The measuring visit is free. We measure each unit and confirm your price.
- 3
We order
Your units are made to measure. Nothing is ordered until you've agreed the price.
- 4
We fit
We agree a fitting date with you. Fitting is usually done in one visit.
Misted glass lets the heat out
Once the seal has gone, the dry air or gas between the panes is replaced by damp air. The window insulates less well, the inside pane feels colder, and the mist won't clear.
A new sealed unit puts that right, with Low-E glass and argon gas as standard. Because we only replace the glass, it costs far less than a new window.
Misting or condensation? Wipe the glass on both sides
It wipes away on the room side
That's condensation from the air in the room, not a failed unit. Opening trickle vents and airing the room helps.
It's between the panes and won't wipe away
The seal has failed and the unit needs replacing.
It's on the outside on cold mornings
That's normal with modern glass, and a sign it's keeping the heat in.
Still not sure? Send us a photo and we'll tell you.
Landlords and letting agents
Privately rented homes in England and Wales need an EPC rating of E or better, unless an exemption applies. The government plans to raise this to C by 1 October 2030. Misted windows are also one of the first things tenants report.
Send us your tenants' photos and we'll quote in writing, arrange access with the tenant and invoice you. See repairs for landlords and letting agents.
Why choose Dr Glass London?
Made to measure
A new A-rated sealed unit, made for your frame. We take the old unit away.
Low-E glass and argon
Low-E glass and argon gas between the panes, as standard. It keeps more heat in than the failed unit.
Your window stays as it is
Same frame, same hinges, same handles. Quicker and much cheaper than a new window.
A fixed price before we order
We confirm your price at the measuring visit. Nothing is ordered until you've agreed it.
20% off 3 or more units
Save 20% on 3 or more units in one visit, so it's worth doing several misted windows together.
5-year guarantee
On every new sealed unit we fit.
Sealed unit prices
Fitted, with VAT. The price estimate above works out the price for your sizes.
-
Standard sealed unit
For most windows.
from £185 -
Obscure unit
Patterned privacy glass, for bathrooms and halls.
from £205 -
Toughened unit
Safety glass, for doors, beside doors and low down.
from £225 -
uPVC door glass
A new sealed unit for a uPVC door.
from £255
Save 20% on 3 or more units in one visit
Prices include VAT, supply and fitting. 'From' prices are for standard sizes. We confirm the final price from your photos or at the measuring visit, before any work starts.
Questions people ask
Can you just clean the glass?
No. The mist is inside the sealed unit, between the two panes, so it can't be reached to clean. Replacing the sealed unit is the lasting fix.
Do I need a new window?
Not if the frame is sound. We replace just the glass unit and keep your frame, hinges and handles.
How accurate is the online price?
It's worked out from your sizes and choices, using our London prices. We confirm the price at the measuring visit, before we order anything. If the size or the glass turns out to be different, we tell you the new price first.
Do I need toughened glass?
Glass in or beside a door, up to 1500 mm from the floor, and any glass lower than 800 mm from the floor has to be safety glass, which is usually toughened. The price estimate only offers safety glass for those places.
How long does it take?
Two visits: one to measure and one to fit. Your units are made to measure, so we agree the fitting date with you. Fitting is usually done in one visit.
Can you match obscure glass?
Usually, yes. There are lots of obscure patterns. Send a close-up photo and we'll match it or suggest the nearest pattern. Obscure units are from £205.
Do you do Georgian bars and leaded units?
Yes. You can add Georgian bars or leading in the price estimate above and see the price, or send us photos. Units with bars or leading are made to order, so we give you a fitting date when you book.
Areas we cover
From our base in Watford we cover west and central London and the areas around Watford, including: