Find a Window Installer you can trust in Leatherhead.

Yes, of course! It’s common for people to replace just one double glazed window. One reason that people want to replace one window is that the sealed unit inside has failed. You’ll know if this has happened because you’ll be able to see condensation on the inside of glass, which gets frustrating because you can’t wipe it away. In this case, you can choose to simply replace the sealed unit or the entire frame, which you might want to do if it’s looking past its best.

When you’re replacing just one double glazed window, if you know the brand of your current windows you could ask your installer if they can source the same ones. This will help to keep them looking as similar as possible, although if your existing windows are very old you may notice some discolouration on the exterior compared to the new one, and locks and trickle vents might look different.

Replacing just one double glazed window shouldn’t take a qualified window fitter long, and could cost as little as £400. If you want to simply replace the sealed unit, that may only cost around £250. You could try to fit a new window yourself, but it’s worth bearing in mind that all replacement windows need to be certified that they’ve been installed to meet building regulations, so you’ll need to apply to your local building control officer who will come and inspect the work then issue a certificate. If you ask an installer who is registered with a self-certification scheme (like FENSA) to fit the window for you, they can issue the certificate themselves when they’ve finished the work.

The energy efficiency of windows is measured using ratings, varying from A, the most efficient, to G, the least efficient. This scheme is run by the British Fenestration Council (BFRC). To comply with Building Regulations you’ll need windows of energy efficiency at least level C.

• Washing up liquid
• Glass cleaner
• A lint-free cloth or rag
• A putty knife
• A paper plate
• Acetone

These days, buyers expect homes to have double glazing. People recognise the benefits of installing double glazing, so if you don’t have it installed you should consider it. You’ll increase your property’s value and give it a better chance of selling faster, since single glazed properties are also more likely to have problems with damp and mould which could put buyers off.

On the grand scale of things there isn’t a huge difference between B-rated windows and A-rated windows. Consumer watchdog Which? have calculated an extra 6.5% would be saved on energy bills with A rather than B rated panes. Be aware that A rated windows are slightly more expensive, however.

Using a Fensa registered installer isn’t compulsory but it helps to protect you from cowboys and rogue traders. It will also make life a whole lot easier in regards to Building Regulations. Replacement windows must meet a certain energy efficiency rating and once fitted you need a certificate to show your installation complies. By using a Fensa registered company they’ll issue this certificate, otherwise you’ll need the council to look at the new windows.

Whether you’re hiring a professional to replace your double glazing or are considering DIY, it’s a good idea to know how to fit a double glazed window.

You need to start by assembling your window. Fit any handles and cut the outer sill to size by measuring the outer wall depth. Then, screw the outer sill to the window frame and attach the frame fixers. Screw the ventilation grilles onto the inside of the frame and fix the vents on.

Next, you need put the window into place, using spacers to wedge it in. Use a spirit level to check it’s level horizontally and vertically, adding extra spacers if needed. Then, fix the frame into place at each fixing point using a drill, wall plugs and screws. Measure and cut the interior sill, and check that it’s level, adding spacers if needed. Then fix it using screws, masonry nails or adhesive.

Finally, fill in any wide gaps with foam filler and small gaps with sealant. You can get interior and exterior trims to cover these up, making your window look neat and professional.

• Thick gloves
• A hammer
• A broom
• A vacuum cleaner
• Thick-soled shoes
• Safety goggles

1. Put your gloves on and use the hammer to remove the rest of the glass. Make sure you hit the glass away from you.
2. Using the broom, sweep away any loose glass from the area, making sure you do both inside and outside.
3. Use your vacuum cleaner to remove any small pieces of glass that you might not have been able to see.