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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.

Unfortunately, you can’t fix the glass on one side of a double glazed window. That’s because they’re sealed units – once one pane of glass is broken, that will break the seal and its thermal insulation properties will be lost.

The good news is that if your window frame is still looking great, there’s no need to replace that. You can simply replace the glass in the window, which will cost much less. You can look to spend around £250 on a sealed unit, whereas a whole replacement single window may cost up to £600.

When an installer comes to replace the glass in your double glazed window, they will survey the inside and outside of your home around the window, then move any furniture by the window so they’ve got access. They should then pop a dust sheet down to stop any debris from getting on your floor.

Then, the installer will carefully remove the beads from the frame. They will then lift the glass out of the frame and put it somewhere safe before cleaning out all of the dust and any debris that has found its way into the frame. Using spacers at the bottom of the frame, the installer will make sure that the sealed unit is square in the frame to get a good fit. Once they’re happy, they will replace the beading and make sure it looks perfect before cleaning up their tools.

You could have a go at replacing the glass on a double glazed window yourself, but it’s not recommended. Leave it to the professionals who will know exactly what to do and will be able to do it quickly and safely.

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.

uPVC is unplasticised polyvinyl chloride. It is a favourite amongst homeowners and manufacturers for its cheap production cost and excellent benefits. uPVC is used for window frames, conservatories and doors. In fact, uPVC can be three times cheaper than wooden frames and is also the most energy efficient option.As well as this, uPVC is now available in a range of colours other than the typically seen bright white finish. It can also be recycled, is durable and resistant to changing weather conditions.

Did you just purchase a double glazed window and confused about how to have it installed? Fitting the window yourself can be quite easy with the help of this step by step guide. However, if you lack proper training or experience, we’d recommend you reach out to a trustworthy professional who can guarantee the best results for help. That said, now let’s take a look at the process.

• Remove the old windows by detaching the old beading and glass window safely. Then make some interval cuts using a hand saw before using a crowbar to pry it out.

• Cut the external double glazed window seal. Once done, take a measurement of the window area’s width once empty. Then transfer the measurement to the window sil to face outside and cut using a handsaw.

• Seal the window sil. Add a bead of clear silicone along both inside lip as well as the centre to seal the sil.

• Screw the double glazed window to the sil. Position the window on the top of the lipped section that was siliconed. Then pre-drill them together and screw in three places. You should make sure the screws do not go totally to the sil’s bottom.

• Install the double glazed window. After successfully screwing the double glazed window to the sil, you can now fit in the double glazing. Make use of packers to make sure it’s even in the slot.

• Screw the uPVC window to the wall. If you’re happy and satisfied with the position of the window, you can then pre-drill through the frame of the window and the brick wall. Once done, simply screw it in place using masonry screws or Spax screw as they do not require crawl plugs in bricks.

• Seal around the window. To do this, simply fill any gaps with expanding foam, wipe out the excess and seal with silicone.

How long your aluminium windows will last depends on their quality. They should last 20 -30 years at least, but have been known to stay in good condition for up to 45 years. This is considerably longer than uPVC and wooden double glazing.

If you’ve got a problem with condensation and don’t have double glazing, you should find that getting new windows will help. Condensation is caused by warm air meeting a cold surface which then turns into water droplets. With two panes of glass, less heat will escape from your home and keep the window warmer, meaning when steam from the bathroom or kitchen touches your windows there should be less condensation.

Most window installers will be able to provide you with one double glazed window and fit it for you. If you’re replacing one double glazed window in your home, ask them to try and source the same windows that you already have or find one that’s very similar. Externally, you probably won’t be able to notice the difference, but if your existing windows are very old there may be some exterior discolouration and the locks and handles might look slightly different.

If you want one double glazed window so you can fit it yourself, there are lots of online companies that can supply you with one window. However, window fitting is a skilled trade and you might want to consider whether you have the right tools and experience to fit it yourself. Of course, you’ll save money on installation costs, but if something goes wrong, you might end up shelling out to get it fixed anyway.

The other thing to consider is that any replacement windows need to be certified that they meet Building Regulations. If you fit the double glazed window yourself, you’ll need to apply to your local council building control officer to get a certificate that confirms that you fitted the window within the regulations. You’ll have to pay a fee for this, and it will be even more expensive if Building Control say that the window hasn’t been fitted within the regulations and you have to start again.

The alternative is to ask a reputable window installer that is registered with a self-certification scheme, like FENSA, to install the window. That means that they can self-certify that the window meets building regulations once they’ve finished the installation.