When we left off last time, I was agonizing over paint colors for my building’s front door, but I hadn’t actually made any progress toward painting the door. (Thanks, by the way, to all of you who offered color suggestions – I still haven’t bought paint, so you’ll have to wait for another post to see what color(s) I end up choosing.) This past week I finally started in on the long list of prep work that needs to be done before I can actually paint the door.
I decided to work from the top of the entryway down, so the first order of business was reglazing the transom window above the door. The window sits about 12 feet above the front steps, making it completely inaccessible with the short step ladder we had on hand. I ended up buying a new, 22-foot multi-position ladder to reach the window. Each side of the ladder can be adjusted independently, allowing it to be safely positioned on the steps. With all of the tall ceilings and narrow staircases in my building, I have a feeling this ladder will be getting some serious use even after this front door project is finished.
When I finally got an up-close look at the transom window, I found that it was a mess of cracked, crumbling, and missing glazing putty. Up until a few months ago when I reglazed a salvaged french door, I had no idea what glazing putty was. It turns out it’s an oil-based putty with the consistency of bread dough that was used to secure and seal panes of glass to the frames of old divided light windows. It’s no longer used on modern windows, most of which are not true divided light windows with separate glass panes. As glazing putty dries out over time, it can crack and flake away from the window, providing an opportunity for water to seep into the frame and rot the window. So every few years the putty needs to be replaced. And the putty on the transom window over the front door was long overdue for replacement.
The putty was in such bad shape that I was able to remove most of it by gently scraping it away from the window panes with a putty knife. I was worried about cracking the glass, so I was careful not to get too vigorous with my scraping. I removed the last, stubborn bits of old putty with a heat gun – the heat softened the putty to the point where I could easily scrape it off the window. If you ever find yourself reglazing a window, it’s technically possible to leave some of the old putty behind so long as it’s securely attached to the window, but it’s easier to apply the new putty without any of the old putty in the way. As I scraped away the old putty, I uncovered the glazing points – little metal triangles stuck into the wooden dividers around the window panes that act as clips to hold the glass in place. I made sure to keep all of the glazing points in place to prevent the glass from falling out of the window while I worked. Once I’d removed the putty and scraped away some of the surrounding loose paint, I was left with this:
There seems to be some disagreement about whether it’s necessary to prime the exposed wood dividers before reglazing the window, but I figured it couldn’t hurt. So I taped off the windows and primed the dividers with an oil-based primer (this is important since the putty is also oil based). Once the primer was dry, I finally got down to the business of actually glazing the window. Most guides to glazing windows suggest removing the window from its frame and glazing it on a horizontal surface. That wasn’t really an option here since the transom window is built-in. So I glazed the window in place, which wasn’t so bad, although standing on a ladder working with my hands over my head for a few hours turned out to be exhausting.
Glazing technique is pretty straightforward, but it takes some practice to get the hang of it. I worked on one side of a pane at a time, packing the glazing putty into the corners between the glass and the wood divider with a putty knife. Then I ran the putty knife along the edge of the divider, removing excess putty and creating a sloped edge. The putty is forgiving – it can be smoothed out with a finger, or scraped out and reapplied if it becomes mangled beyond repair. Here’s the window after I finished glazing around all 10 of the panes:
Once the putty has dried, I’ll clean off the oily residue on the windows left behind by the putty (the smudges in the pictures above). The instructions on the glazing putty suggest waiting 7 to 14 days for the putty to dry before priming and painting, but if the hot, swampy weather we’ve had in Boston for the past few days keeps up, it’ll probably be at least two weeks before the putty has dried enough to be painted. In the meantime, I’ll continue scraping the loose paint off of the door and surrounding trim.