How to Replace Greenhouse and Shed Windows

DIY window replacement in 10 simple steps

Most people can do a great job of replacing a windowpane in a greenhouse or shed if they have a little DIY experience. Here's how to do it.

1. Measure the dimensions of the window frame to make sure you get the perfect fit, then send or bring your measurements to us and we'll cut the polycarbonate or acrylic sheet to size for you
2. Gather together your equipment - a putty knife or old butter knife, heavy-duty work gloves, tape measure, razor blade, some glazing points, window putty or adhesive silicone sealant, plus your acrylic or polycarbonate replacement pane
3. It makes sense to protect your eyes with goggles, just in case, and cover the floor beneath your working area with newspaper
4. Remove the broken glass and sweep up all the broken bits – that's why you need thick work gloves. If there's old glass stuck in the frame take great care, gently hooking out the biggest shards first. and the small ones last. If it's stuck fast, you can often get a pane out by gaffer-taping over the outside of it, making sure all the shards are taped, then using a hammer to gently dislodge the pane. Goggles and gloves are a must at this stage
5. Loosen all the old putty using a putty or butter knife, making sure you get it all off to leave a clean surface. You can shave off any awkward scraps using a razor blade or craft scalpel
6. Remove the old glazing points and make sure you have a smooth, even and clean surface to fix the new pane too, otherwise, you'll compromise its structural integrity
7. Evenly apply putty or adhesive silicone sealant all around the edge of the frame, creating a uniform look
8. Gently press the new pane into the putty or sealant, using glazing points to make it sit squarely in the frame - 2 -3 glazing points on each side of the frame is good, more if the pane is a big one
9. Apply a final layer of putty or sealant evenly along with the entire frame and give the outer edge a neat 45-degree angle, using the face of your knife blade. This helps protect the junction and frame itself from condensation and rain
10. Remove any debris then let the putty or sealant dry fully

If you still aren't confident in installing the window yourself, then get a professional in!