![\"\"](\"https:\/\/www.rightmove.co.uk\/home-improvements\/content\/uploads\/2020\/04\/window-replacement-2-1024x683.jpg\")
<\/figure>\n\n\n\nStep 1: determine what you\u2019re replacing<\/h2>\n\n\n\n
We\u2019re assuming you\u2019ll be buying the new window from a supplier rather than building all the woodwork or uPVC yourself. Most of the time, people will be replacing the sash (the frame that holds the window pane) rather than the whole frame or casing (the part that joins the sash to the wall). Opening or half-opening windows can be ordered whole so you can install the whole thing as one piece.<\/p>\n\n\n\n
Step 2: measure up<\/h2>\n\n\n\n
The most important thing here is never to assume your window is perfectly square. Measure it at three points horizontally and three points vertically, and make sure you\u2019re measuring the component you\u2019re replacing \u2013 don\u2019t measure just the sash if you\u2019re replacing the whole construction. Finally, measure it diagonally both ways. If both measurements are within 1 cm of each other, you\u2019re fine. If not, this is probably a professional job.<\/p>\n\n\n\n Now you can order the window from the supplier. Remember to subtract about 1\u20131.5cm from your measurement. You can easily fill the gap, but if it is exactly right or a bit too big, you\u2019ll never get it in place.<\/p>\n\n\n\n WEAR SAFETY GOGGLES AND GLOVES for this part, as glass can shatter at any moment. Unscrew any opening windows and put them to one side. For the fixed windows, scrape out any putty that\u2019s holding the panes in place, or remove trims, nails and edging that could be holding the panes firm. Assess how the frames are held in place. If they are screwed or nailed in, you might be able to remove them. However, as the sashes will be sealed and possibly painted, you might need to resort to a crowbar or heavy hammer to remove them.<\/p>\n\n\n\n Assuming the window is a whole single construction, this will be the first time you\u2019ll see if it fits. Hopefully, it will fit snugly in the opening. Screw your outside brick mouldings to the frame \u2013 they are usually finished at 45\u00b0 so they fit together like a picture frame. This will stop the frame falling out when you insert it from the inside. Next, place the new window panel in the opening, and press it against the mouldings. Check the window is level; if it isn\u2019t, place spacers under the relevant side at the base. Now you can screw the panel to the frame on all four sides.<\/p>\n\n\n\n There will be a narrow gap all around the panel, so you\u2019ll need to fill it with caulk for insulation and waterproofing. On the outside, insert the windowsill at the bottom to ensure rainwater drips over the edge of the wall and not into the brickwork (the edges don\u2019t need sills). Nail or screw it into place.<\/p>\n\n\n\n Finally, since there will be lots of exposed screws, caulk, spacers and possibly brickwork, attach all the trims you need inside and out, and finish off the joins with a waterproof silicone filler.<\/p>\n\n\n\n![\"\"](\"https:\/\/www.rightmove.co.uk\/home-improvements\/content\/uploads\/2020\/04\/window-replacement-3-1024x683.jpg\")
<\/figure>\n\n\n\nStep 3: ordering the window<\/h2>\n\n\n\n
Step 4: removing the old window<\/h2>\n\n\n\n
![\"\"](\"https:\/\/www.rightmove.co.uk\/home-improvements\/content\/uploads\/2020\/04\/window-replacement-4-1024x714.jpg\")
<\/figure>\n\n\n\nStep 5: installing the new window<\/h2>\n\n\n\n
Step 6: finishing off<\/h2>\n\n\n\n