Working With Integrated Metal Weatherstripping

Integrated metal weatherstripping is the mac daddy of the weatherstripping world. It is extremely effective, very long lasting, and fairly difficult to work with. Installing new integrated weatherstripping on a window that did not previously have it is beyond the scope of this post, as it requires precise modification of the sash with routers and very careful templating.

However, restoring a window with this type of weatherstripping requires some additional knowledge that I can share with you about how to safely remove and reinstall both the sash and weatherstripping without damaging either. Let’s look at some of the tools you need to get the job done properly.

• Hammer
• Trim Pry Bar
• 5-in-1 Tool
• Needle Nose Pliers
• Nail Set
• Cat’s Paw Pry Bar

If you’re a more visual learner, and who isn’t these days , then you can see the whole removal process in action in the video below. I don’t cover the whole restoration process of the window jamb and sash in this post or video, but you can watch the whole step by step process in my intensive, self-paced teachable course called The Window Course where you get all the goods on restoring historic windows.

How to Remove Window Sash

It would seem that a sash with this type of weatherstripping are permanently stuck in the jamb since it appears to be trapped in the weatherstripping fins on the sides, but that is not the case. There are just a few more steps before you can remove the sash without damaging it.

The first step to any of this is to have both sash cut free of excess paint or caulk, because the sash need to be able to be moved up and down during this process to access the nails on the metal weatherstrips. So, start with getting the sash at least somewhat moveable again if they are stuck, and then you can proceed with removal.

If you’re not sure how to do that then checkout my resource page DIY Window Restoration for detailed instructions. In this post my focus is on the special consideration for working around this unique metal weatherstripping.

Step #1 Remove Stops

Just like on any other other sash, remove both interior stops by scoring the paint and prying them off the jamb.

Step #2 Remove Lower Sash & Weatherstrip 

Make sure the bottom sash is in the lowest position possible so that you can access the the top portion of the metal weatherstrip on each side of the bottom sash. You should see one small nail at the top of the metal. Slide your flat pry bar or 5-in-1 behind the weatherstrip in this area and gently pry the metal out so that the nail pulls out from the surface a bit. Then, push the metal back, leaving the head of the nail proud of the surface enough that you can pry it off with your cat’s paw pry bar or a pair of needle nose pliers.

You have to be gentle with this weatherstripping because it is very thin zinc, which is relatively soft and can tear and bend easily.

Once the top nail is removed on both the right and left side of the jamb, raise the lower sash up enough to reveal the lower nails (usually just one or two toward the bottom) and follow the same procedure above to pull the nails out.

If you can’t get these nails to pry out, then the fail safe option is to use your nail punch to punch them into the wood through the weatherstrip so that the weatherstrip is now free of the nails. It may have a small nail hole in it, but that won’t affect the performance.

Once both weatherstrips are free, you should be able to slide them up over the stool and get the sash out of the jamb along with the weatherstrips. Cut or disconnect the ropes and your bottom sash is free. Label everything so that you know where it goes when you reinstall.

Step #3 Remove Upper Sash & Weatherstrip

Start by removing the parting bead on both side of the jamb, then make sure the top sash is in the uppermost position and using the same procedure above, remove the two lower nails from the weatherstrip on each jamb. There should be enough space to use a cat’s paw to pull the nails out once they are clear enough from the surface.  

Lower the upper sash to reveal the one or two upper nails, which will be located near the top of the jamb and around the pulley. Pry and remove these nails the same as before from both sides.

Cut or disconnect the ropes and remove the upper sash from the jamb along with the weatherstrips. Be carful that the weatherstrip does not fall, as it can be harmful to you or to the sill, stool, or hardwood flooring upon impact. Mark the location on the backs of each piece.

Step #4 Restoration of Weatherstripping

Once you have the sash out, you are ready to follow the sash restoration process that I teach in The Window Course with a couple of additions. There will likely be an interlocking piece of metal weatherstripping on the meeting rail of both sash that mates when the sash are closed.

I leave these in place because there is no reason to remove them. They can be cleaned up and realigned to make sure that they fit into each other without kinks or other problems. These can be easily bent if you’re not careful and before installation, double check to make sure that they are still lined up and free of any paint or other gunk that would impede operation.

I also leave the piece of weatherstrip on the top of the jamb and on the sill to be cleaned of paint in place and sanded smooth again. There is no reason to remove it and it usually causes more issues when it is removed because you’ll need realign everything later.

I also take this time to clean up the old weatherstripping with 0000 steel wool to clean off any paint or dirt and make them more attractive and ease the operation when they are reinstalled. Bend back any kinks and get them ready to go back in.

Step #5 Install Upper Sash & Weatherstrip 

Installation is made much easier with a helper to hold things in place. You can do it on your own, but it sometimes feels like you need three hands.

Start by installing both the upper and lower sash weatherstrips on one side of the jamb first (only do one side!) Nail them back where they went using the same or similar sized nails as they were originally attached with and nail in the same locations roughly. Then, install the parting bead on that same side.

Attach the ropes to the upper sash on both sides. Tack the rope in place on the sash with a nail for added security to keep it from pulling out.

While holding the loose piece of weatherstrip in the groove along the edge of the sash, slide the sash into the weatherstrip previously nailed onto jamb and pivot the sash into place against the blind stop. The loose weatherstrip should be pushed to the top of the jamb and fit against the weatherstrip on jamb header. Nail off the top of the weatherstrip at the top and around the pulley like it was previously attached.

Raise the sash all the way up and nail the bottom portion of the weatherstrip. Insert the remaining parting bead and test the operation of the top sash.

Step #6 Install Lower Sash & Weatherstrip 

Following much the same procedure as above, attach both ropes to the lower sash and tack the rope in place with a nail for security.

While holding the loose piece of weatherstrip in the groove along the edge of the sash, slide the sash into the weatherstrip previously nailed onto the jamb and pivot the sash into place against the parting bead. This time, the loose weatherstrip should be pushed to the bottom of the jamb and fit against the weatherstrip on the sill. Nail off the bottom of the weatherstrip where it was previously attached.

Lower the sash all the way to the sill and put a single nail in the top of the bottom weatherstrip. This one is usually a tight fit, so a nail set is best for getting this nail fully set.

Check that all nails are fully set but not punching through any of the metal weatherstripping. 

Install the two interior stops and then test the operation of both sash to ensure that you’ve got a smooth up and down. If you need to tweak the fit of the interlocking pieces on the meeting rail so the sash close fully, this is a good time. Also, it’s possible that the alignment is not perfect for the sill and header piece of weatherstripping that you left in place. They may also need to be tweaked a bit as well.

That’s it! You’ve just restored sash and maintained the most effective form of weatherstripping you can get. My hope is that this tutorial will encourage you to save not only your historic windows, but also that long lasting metal weatherstripping to keep them efficient for another hundred years.

If you’d like to learn more about restoring your historic wood windows check out my book Old Windows In-Depth or my course The Window Course. You can restore these old beautifies yourself, and with a little elbow grease you can save ten’s of thousands of dollars by DIYing it. That what this blog is dedicated to helping you do better!