You might want to put a drop cloth on the other side of the window too, just to be safe.
If you’re wearing goggles, make sure they wrap around your eyes to protect them from all sides.
If the glazing is tough to get off, try heating it up with a hairdryer or heat gun. This can soften the glazing and make removing it easier. [4] X Research source You could also use a razor or utility knife to get the glazing off.
If the pane was already broken, then you might not have to crack it more. If you can get a grip on the pane, then you can just pull it out. If you’re removing a pane in a loose window sash, the wooden part that holds the panes, then you can place it on a workbench, cover the pane with a rag, and hit it with a hammer instead of taping it. [7] X Research source
You’re only trying to crack the pane. You don’t have to smack it hard to try and smash it.
If there isn’t a spot to grab the pane, then try going to the other side of the window and pushing it out. Even though you taped the glass, some shards might still break free as you remove the pane. Check the floor and pick up any loose pieces. Some windows use hooks or other small metal pieces to keep the panes in place. If you see any of these, pull them out as well.
Keep your gloves on while you’re sanding. If you missed any glass pieces, you could get a serious cut.
Since wood expands, leave a bit of extra room to allow for that. In general, subtracting 1⁄8 in (0. 32 cm) from your measurement leaves enough room. So if your sash space is 12 in (30 cm), get a pane that’s 11 7/8 in (29. 7 cm) for some extra room. If you can’t get a pane that fits into the sash, you could also get a larger piece of glass and cut it to fit into position. Hardware stores will also cut the pane for you if you bring your measurements in.
Work quickly after this so the caulk doesn’t dry before you put the glass in. In general, silicone or polymer caulk is recommended for windows. These are flexible enough to expand with the window and make a weather-tight seal. You could also use butyl rubber. [14] X Research source
Make sure the pane is completely in the sash before letting go of it. If it’s still loose, it could fall out and break. Do your best to line up the pane perfectly the first time. Removing it to reset it will make a mess and could break the glass.
You can get glazer’s points at hardware stores. If the pane is 12 in (30 cm) or longer on any side, then put points every 4–6 in (10–15 cm) instead.
Putty usually comes in pre-made ropes. You can get it from the hardware store. Window putty or glazing also comes in a caulking tube. You might find this easier to work with. If you use it, apply it the same way you would apply caulk. [18] X Research source
Don’t worry about keeping the putty neat. You can clean up the edges afterward.
If any putty gets on the glass, scrape it off with your blade before it dries. If you can see putty sticking out from either side of the window, then there’s a bit too much. Scrape this off as well so the window looks nice and neat.
When you’re picking up your drop cloth, fold it up carefully and carry it to a garbage can to dump out. Check carefully for any shards of glass that might have fallen out while you were working.
Don’t try to paint until the putty is completely dry. Scrub the window when you’re done to get rid of any excess paint.
