Restoring Wood Windows: Weights and Weatherstripping

by Josh on December 31, 2009 · 10 comments

in Bedroom,Projects,Windows

Continuing the restoration of window frames and hardware I talked about in my last post, this entry completes the restoration of the frame portion of the project bedroom windows with new cord on the sash weights and weatherstripping that will keep these 86-year-old windows comfortably draft-free and energy-efficient.

Sash Cord and Weights

There is just something genuine about the mechanics of old double-hung windows. Their simple combination of pulleys, weights and rope achieves an amazing result: leveraging gravity to hold something up. Plus today’s windows with vinyl friction jambs just can’t compete with sash weights for smooth operation or longevity. Embrace your weights!

New sash cord on weights

To ensure a long-lasting restoration, I replaced all the sash cord with new 1/4″ nylon cord.  My local True Value hardware had both nylon multipurpose rope and cotton-over-nylon sash cord.  I chose the nylon for its superior strength and resistance to rot, though the look of the nylon casing sacrifices a bit of authenticity.

To tie the sash cord to the weights, I picked the bowline knot from my repertoire of old Eagle Scout skills. The bowline is a good choice for this application because it forms a loop that does not close– once the knot is tight, there should be no slippage that could take the weights out of adjustment.

Window weights installed

The tied weights then go back in their pockets alongside the window jambs, with the sash cords fed up and over the reinstalled pulleys.

Weatherstripping

My principal reference for how to restore these windows is a book I’ve mentioned before: “Working Windows” by Terry Meany. Meany recommends a combination of modern and traditional weatherstripping for old couble-hung windows that I have implemented here.

For the lower sashes, Meany calls for traditional spring bronze, sometimes called brass spring, nailed to the jambs.  Although this material is less commonly available than it once was, I had no trouble finding it at a store right in my neighborhood.

Setting nails in weatherstrip

Installing spring bronze is a bit putzy because it must be nailed every inch-and-a-half or so. It’s also important to use a nailset to sink the nail heads a bit or they will gouge up the sides of the window sashes. My spring bronze is cut to one inch longer than the height of the lower sash and trimmed to a curve on top to prevent damaging the sash or bending a corner on the weatherstrip when the sash is fully opened. To create the spring action in the spring bronze, run a slotted screwdriver down the groove you’ll find next to the nailing edge of the weatherstrip.

Weatherstripping installed

If you look closely at the picture above you’ll see a section of white vinyl weatherstripping for the upper sash in addition to the fully-installed spring bronze. The reason spring bronze isn’t ideal for the upper sash is that there is no way to use it around the pulley.  Adhesive-backed vinyl “V” weatherstrip fixes that problem– here’s how:

First, some background: the vinyl weatherstrip comes as a roll, typically sold in nice, round, 17-foot lengths.  The True Value hardware nearest to me had it in stock in both white and brown for just a few dollars a roll. Also, you may see it labeled as 7/8 inch wide, but this is the unfolded width.  Folded, it is… wait for it… half that width (7/16″). Because it is installed folded, 7/16″  is the more useful and accurate width dimension.

Folded vinyl weatherstrip

Unlike the spring bronze, which was installed on the jamb of the window frame, the adhesive vinyl is attached to the exterior stop.  The exterior stop is the part of the window frame that forms the outside edge of the “track” that holds the upper sash.  Correctly installed, the “V” of the weatherstrip will point to the corner.  The following picture shows proper installation and how this fixes the “pulley problem” I mentioned above.

Upper Sash weatherstrip installed

When the upper sash is reinstalled, I will close the “V” as the sash is positioned. The weatherstrip will then press against the upper sash and prevent air from infiltrating through the space between the side of the sash and the window frame. Although the vinyl material and adhesive attachment method are far less durable than the spring bronze, the upper sash is also a less demanding location than the lower sash, so I expect it to hold up well.

Paint removal was the most laborious and hazardous part of the window restoration I’ve undertaken so far. But if you have old double-hung windows that don’t require paint stripping– or if you can hire someone else to do that part of the work– I think many people would find weatherstripping an easy and affordable DIY project.

Disclosure: I was one of five bloggers selected by True Value to work on the DIY Squad. I have been compensated for my time commitment to the program and my DIY project as well as my posts about my experience. I have also been compensated for the materials needed for my DIY project. However, my opinions are entirely my own and I have not been paid to publish positive comments.

{ 10 comments… read them below or add one }

Eric December 31, 2009 at 4:03 pm

I’ve really enjoyed reading your window restoration. I remember playing with the weights as a boy when my dad would work on our windows.

What would you recommend using to lubricate wooden window sashes?

Reply

Michael January 6, 2010 at 11:22 am

Lubrication: I have found that candle or bee’s wax rubbed on the track works well.

Stripping: As long as you keep it away from the pane of glass, the Silent Paint Remover has been a real helpful tool as long as you wear a mask to keep the smell of burning paint away from everyone. For those hard to reach places, I have used Citri-Strip sealed under cling wrap (those moving rolls work well) – but you have to wash it off with water and it takes time to clean it off with a solvent afterwards.

I bought my Silent Paint Remover to hand scrape the entire exterior of our carrage house with wooden slat… and after using it on old wooden furniture and built-ins it’s a very efficient way to get chipped paint off of anything.

Reply

David March 19, 2010 at 10:26 am

Eric, friend of mine using bearing grease but bee’s wax working well too. Regards

Reply

justin April 12, 2012 at 1:03 pm

Hello Josh,

I’ve enjoyed reading your blog, keep up the good work and spreading the word about old windows!

Best regards,

Justin Smith – Owner, http://www.smithrestorationsash.com/

Reply

Scott March 3, 2013 at 11:27 pm

Nice article on weatherstripping. We’re getting ready to do a whole bunch of windows and I always like to read up and see what’s working for other folks. Gotta love those old windows!

Reply

Liz June 17, 2013 at 12:04 pm

Did you take off the whole side of the window to access the weights?

Reply

Liz June 20, 2013 at 11:35 am

Also, Terry Meany recommends installing the vinyl against the parting bead, not the exterior stop. Thoughts?

Reply

Debbie September 16, 2013 at 10:52 am

I was told by Terry Meany himself that the v vinyl goes on the parting bead and not the exterior stop. The reason being that when you lock the window it draws the sashes together compressing the v vinyl and making a tight seal. Placing it on the exterior stop will creat a wider gap between the upper sash and the exterior stop as the upper sash in drawn in when locked. Makes sense to me!

Reply

Josh September 16, 2013 at 11:10 am

Thanks for the helpful correction, Debbie (and Liz above). I’ll update the article.

Reply

John Sisk October 24, 2013 at 4:21 pm

Enjoyed the read keep up the good work :-)

Putting together notes on sash windows and casement windows on are website I hope your might find them interesting please see

http://www.sashrepairs.co.uk/info/

Kind regards

John.

Reply

Leave a Comment

Notify me of followup comments via e-mail. You can also subscribe without commenting.

Previous post:

Next post: