Find a Window Installer you can trust in Dunfermline.

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.

Removing a double glazed window can be quite labour intensive. If you decide to try it yourself, make sure you give yourself plenty of time, and wear gloves and goggles.

Begin by unscrewing all opening windows at the hinges and removing them. Then take away the beading and putty around any fixed panes and take them out too.

Once you’ve removed all the glass, use a saw to put angled cuts in the frame, and a bar and hammer to remove it in sections. You should remove the sill if you’re going to replace that too.

Finally, cut through any screws holding the frame into place with a hacksaw.

You can only repair blown double glazed windows in the sense that you can replace the sealed unit (the glass part of the window) instead of having to replace the entire window.

When a double glazed window is blown, it means that the seal around the window has failed and is now letting air in and out. Often the first sign that the sealed unit has blown is condensation on the inside of the window, which is annoying since there’s no way to get rid of it! When your sealed unit has blown, you’ll be losing heat out of the window, meaning you could be spending more on your energy bills.

As a temporary fix, you could see if you can buy a misting repair kit online, but the condensation will eventually occur again as the air gets in. The best thing to do is ask a window installer or glazier to replace the sealed unit for you.

It's simple to replace the glass in a window – the specialist will remove the beading around the window, remove the blown glass from your window frame and set it to one side. They will then clean up around the frame before adding spacers in, then fitting the new sealed unit into the frame. They’ll make sure it’s a snug fit before replacing the beading back around the window to secure it.

There's no reason to put off repairing a blown double glazed window since the cost is generally much less than replacing the entire thing. A sealed unit with installation costs an average of £100, whereas a completely new window will cost around £400. You’ll soon notice that it’s less draughty and will be able see out of your window once you’ve had the blown glass replaced.

1. Using a rubber mallet and a strong pallet knife, remove the beading around the window. You might think they’re part of the frame, but they’re actually separate on the inside of the frame and can be taken out by using pallet knife to prize them out. Start with one of the longest beads first and leave the top bead until last.
2. Give the glass a little tap to loosen it if it doesn’t come out straight away, then the whole unit should slide out easily. Just make sure it falls towards you and not back out onto the ground below!
3. Clear any debris that has found its way into the frame with a brush. Add spacers at the bottom of the frame – these could be pieces of plastic.
4. Get your new sealed unit (make sure you measure the glass before you buy one so you know which size to get) and carefully take it out of the packaging. Look for the British Standard mark – that shows you the bottom of the glass.
5. Lift the glass into the frame, starting with the bottom first, and make sure that it fits square in the frame before taking the spacers out.
6. Use a little washing up liquid to spread along the beads to make it easier when you slide them back into the frame. If they simply push and clip back in, you can use something like a block of wood to help you push them in correctly. Put them back in reverse order to how you took them out.

To install one small double glazed window, it will take anywhere between two hours and half a day. It will depend on whether one installer is fitting your window or two. And if you’re doing it yourself and don’t have any professional experience, it will take even longer.

When the window fitters arrive, they will make sure they’ve got safe access to the window and move any heavy furniture if they need to. Any good installer will lay down a dust sheet, but it’s a good idea to check that they’ve got one laid down before they start.

The first step any window installer will take is to double check the measurements of the new frame against your existing one. Hopefully it should match up, so then they’ll take the old window out. Then, they’ll insert the new frame into the aperture and bolt it into the concrete. They'll check it with a spirit level to ensure it’s even before moving onto the glass sealed unit.

The installer will place the glass into the aperture, then fit the beads to secure the glass in the frame. They’ll then use silicone and trim on the inside and outside to ensure the window looks perfect. You won’t be able to see where they’ve used sealants or trims because they’ll colour match them so it’s not noticeable. Then, they’ll tidy up all of their tools and the working area and let you know what needs to be done in terms of proving that the window meets building regulations. Most good installers are registered with a self-certification scheme, so will be able to issue a certification once the work is complete.

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.