How Do You Remove A Sash Window?
Have a look at some signs that you need to replace your sash windows
Windows are worn out
Signs of rot or warping on your windows or that the double glazing is failing are big indicators that you need to replace them.
Wooden window frames in particular can be tricky to keep in good condition. The trouble is, once rot has set into the wood, it can be pretty hard to halt the decay and keep on top of it. Rain becomes a nightmare and you might find it’s just too difficult a job to fix the window so it still looks good and does its job properly. Of course, if you just leave it, the rot will get worse, and it will become harder to open or close the window.
Poor quality uPVC windows may discolour over time and as they expand in heat they can become warped. If your double glazing is failing you may notice water leaks, condensation, cracks, chips, holes and scratches. This makes it difficult to regulate the temperature in your home.
Energy bills are high
Old or inefficient windows can have a significant impact on your home’s insulation and can lead to high energy bills. The more heat that is able to escape your home the more you will be using your central heating to compensate, and the same is true of using air conditioning. You can check this by standing next to your windows and seeing if it feels cooler than the rest of the room. If the glass is cold to touch then it’s highly likely you’re wasting energy. You should also look for gaps in the frame.
Older windows are often single-paned and therefore more vulnerable to leaks. It’s a very good idea to invest in double glazing with argon gas and low-emissivity (LoE) glass to reduce heat loss.
Fitting New Sash Windows
Option 1: Fitting Brick-to-Brick
This essentially means your window will be installed sandwiched between the brickwork either side of the opening. Windows installed this way may be slightly more proud – so if you have a stone sill, it may sit further forward, giving you less of a sill.
Option 2: Fitting within the Reveal
With this option, your window will sit behind the brickwork into the reveal either side of the opening. If you have a period house that originally had sash windows, this space may have been where the weights and pulley would have been. With this option, there’s more room on the inside of the house than the outside. I also recommend checking the depth of space you have available here against the depth of the window too – to make sure this option is totally viable.
Taking the Correct Measurements
Measure the external opening of your window, taking a minimum of 3 measurements across both the height and the width to check for any disparity. If there is, you should always use the smallest measurement.
If you’re fitting brick-to-brick, you should deduct 10mm to both the height and width. If you’re fitting within the reveal, add 40mm to the width and 20mm to the height. Once you have these measurements, re-measure and check the window will fit.
Removing the Old Window
If it wasn’t already obvious, you will have to remove the old window first. How your window is attached really depends on the type of window you have and how it opens. For our window which only has a very small top section which opens, we needed to remove the glazing to get at the screws. However, if your window fully opens, you may be able to see the screws when the window is in its open position and you won’t need to remove the glass. It is, however, often a good idea to remove the glass so the window weighs a lot less and will be easier to manage!
To do this, you’ll need a filling knife and a glazing hammer. Hit the beading around the edge of the glazing to pry it away from the glass.
Once you’ve removed all four pieces, you’ll be able to simply take the glass out and you can then access the screws hidden behind the glass. If you have expanding foam around your window, it may be necessary to remove this as well. We had lots of plastic trim on the outside which also needed removing too. Again, a filling knife works great for this!
Once you’ve removed any excess trim, you can untighten those hidden screws and simply remove the whole frame from the window opening.
Removing the old Sash Frame
If the original sash frame is still hidden behind your window, then this will need removing too. Sadly does indeed removing the original weights too, and yes, I was sad about this – but the way I see it is that the original window is long gone, I can’t preserve what’s now been left, so the best thing I can do, is installing a new period window to put back some of those original features.
To remove the old sash frame, you’ll need to cut away the wooden sides and pull out the weights (don’t worry, we plan on using ours as decoration elsewhere in the house!). You’ll also need to remove the old wooden sill, leaving the new window to sit directly on the stone sill.
Step 2.5 – Packing the Sides with Wood
If you’re fitting your new sash window within the reveal, then you won’t need to do this. But, as we have an original shutter casement around the window, we aren’t able to push a window into that space as the casement protrudes too much. So instead we’re using the brick-to-brick method, but packing the sides with wood and fitting it flush against that.
We selected some wood that was the perfect depth to match the brickwork. We then cut this to size and screwed in place, filling the gap of the frame we just removed.
Step 3 – Levelling the Base
You’ll need to sit the new uPVC sash window onto a level base. The recommended approach for this is either to use shims place across your sill or sitting the window on a bed of mortar. We felt the shims approach was much easier.
Lay several of them across the bottom of the opening and use a spirit level to make sure it’s perfectly level. If it isn’t, you may need to use different sized shims to even it out. Make sure you use a shim in each corner below the jambs as well.
Step 4 – Lifting the Window into Position
Sash windows are much heavier than usual windows, so you’ll need a minimum of two strong people to lift the window. If you’re lifting the window particularly high, it may be necessary to use a platform.
Lift your window onto the shims or bed of mortar you laid in the step above, and position it centrally, so there’s an even gap either side. If you’re using the brick-to-brick method like us and measured the opening correctly, there will be about a 5mm gap either side. You may have a larger gap if you’re fitting your window within the reveal, but you want to make sure the window looks central from the outside of the house.
Step 5 – Packing the Sides with Shims
Your window must be absolutely level in order to work properly, so although we’ve levelled the base, you’ll now need to make sure it doesn’t have any lean inwards or outwards. Use a spirit level to check this, as you continue through this step!
Providing your window is level, you should then pack the sides of the windows using the appropriately sized shim. This should be the perfect size for the gap, so when slotted in, it’s holding itself in position. You may have to use a couple of shims together if you have a larger gap and don’t have the correct size shim.
The packing shims will stop the frame from being pulled into the bricking (bowing it) as you screw the window to the wall. If the frame is pulled in, the sides of the frame will push out towards the brickwork and you’ll end up with gaps either side of the actual sash window. Make sure to pack the sides out really well and ensure you use shims in the locations where you’ll be adding the screws too.
Step 6 – Screwing the Window Into Place!
The recommended approach to fitting a uPVC sash window is to using fixing brackets. If you can use the brackets, they look incredibly easy to use – but they aren’t fixable on every period property. As an alternative, screw through the frame, however, unlike other windows, a sash window has spring either side concealed within the frame, so you’ll find there are very few suitable spots available to place your screws.
If you would like to look at our outstanding range of sash windows, get in touch with us today.