How to Rebuild Your Old Windows

This article will show you how to fix older windows that have more problems than just broken sash cords. It will help you complete the job and make the windows look as good as new.

Difficulty: Challenging

Instructions

Things You'll Need:

• Goggles to protect your eyes
• Pliers to pull tacks
• Razor blades
• Chisel
• Rubber hammer
• Glass cutter
• Paper towel
• Glazing compound
• small tools available
• flat corner brackets

1. If you are thinking about replacing these old windows it must not just be because one or both sash cords holding the weights have broken in one or more windows. The windows with broken cords are now guillotines that can hammer your fingers in free fall just because you do not always remember which windows have inadequate counterbalancing weight. If one of the weights is missing, the window tilts to one side, making it hard to slide up. Replacing the cord is easy but can generate a paint job, because the removable sections of the window frame usually have layers of paint that have filled in the gap between pieces of wood. If you do not have the original paint, you will likely be painting the window frames over. Since you will likely need to paint one or two window frames, it will be wise to replace the sash cords for all the windows in a given room at the same time.
   
   That was the good news now comes the real reasons why people want these windows out:
   1) The top window is welded by paint and refuses to move.
   2) In trying to force the window to move, usually the bottom of the window frame separates from the rest of the frame.
   3) Pieces of grout (glazing compound sealing the glass to the wood from outside) are missing, letting cold air pass through.
   4) The locking window hardware is loose because the wood is falling apart and no longer holds the screws
   5) The storm windows chew up your fingernails and make you want to scream.

2. Let us assume that you can manage to remove the windows and want to start fixing them.
   Soon you will discover that the reason why the bottom of the frame comes off is because the wood is rotten at the lower corners. The good news is that you can add metal corner brackets (outside) that reach into the healthy wood and strongly hold the frame together.
   That old glazing compound is no joke. Your ability to remove that glazing compound will let you know if you are capable of fixing these windows. I have fixed over thirty of these windows and can tell you that removing the glazing compound is the hardest part. The stuff is hard as rock and is welded to the wood. If you try to separate it from the wood by force, it will instead split the wood in places where you cannot afford to lose any wood. Some windows have 13 different pieces of glass individually framed within the larger frame. Removing the hardened glazing compound from these skinny inner frames requires the use of different techniques. I would advise against using a torch to soften that glazing compound because you can start a fire. I have used a rotary saw with a small radius to cut in between and separate the wood from the glazing compound. If you use a similar saw, you will have to keep a safe distance from the corners. You do not want to cut the inner or outer frame corners. Use another method to remove the hardened glazing compound from the corners. Try a chisel without the hammer, grinding drill bit, etc.

3. I had it easy with the glass only after I stopped trying to save the old glass. At first I only replaced the broken pieces of glass. Once the broken pieces were replaced, I soon realized that the "new" glass was clear while some pieces of old glass had a layer of dust that was embedded in the glass and was not attractive at all. I found myself replacing these pieces as well.
   Since I had been a picture framer for years, I knew how to cut glass and I recycled glass from other discarded windows that were not as old as the ones that I was fixing. Finally, you need to be able to replace the rot with epoxy. If you need to fill in a gap in the wood, try to first screw some anchor screws below surface height. When the surface level is flat, it is easy the match the epoxy to the shape of the wood. However if the rot was located in a curved part of the frame, you will need to use the following procedure. Find a section of that curved molding that looks perfect. Mix enough epoxy to make a rectangular prism that is about 3/8 of an inch thick, 3 inches long and wide enough the cover all the curves in that molding. While the epoxy is still soft, spray some lubricant on the perfect section of the molding. Now, place your soft epoxy block on the molding and use a piece of glass to press down on it gently. Let the epoxy harden on the lubricated molding.
   Once that piece of epoxy hardens it become the piece (the stamp) that you will use to duplicate the curvature of the molding at every location where you fill in with epoxy.
   Remove the rot and fill in the gap with soft epoxy, and then gently press down on the soft epoxy with the hardened lubricated epoxy block.
   It would be a good idea to relocate the locking hardware after filling the holes left by the old screws as well.

4. Once the frame is rebuilt, I suggest that you reassemble the window using he following procedure:
   1) Clean each piece of glass on both sides before placing it in the frame.
   2) Buy staples that are 3//8 of an inch long. The staples should have pointy tips (not square) that can penetrate the wood easily. Use a utility knife to separate each staple from the string, by slicing them loose one by one.
   3) With the window frame laying plat on a table, place a piece of glass into the frame. Place a staple on the edge of the glass with the pointy tips facing the wood. Grab the body of a chisel firmly in your fist with the handle pointed up near your thumb. Use the tip of the chisel to gently push the single staple into the wood. You should have a good grip on the chisel allowing you to control how far the staple travels into the wood. You want the part of the staple that is not inserted into the wood to trap the edge of the glass. But, you do not want that exposed part of the staple to project so far that it sticks out of the glazing compound that will be applied next. The alternative is to use tools that drive tacks by impact. These tools routinely break the glass.
   4) Now it is time to apply the glazing compound. Use the palm of your hand to roll long strips of glazing compound.. Push these strips all around the edge of the glass on the back part of the window. Make sure that you do not miss a spot and press the glazing compound firmly against the wood. It will be wise to repeat this procedure (do it twice) for every piece of glass. In others words, it will be best if you remove the glazing compound that you just placed around the frame, reshape it into long strips and reinstall it. The first time you apply the glazing compound , it makes contact with all the loose wood particles. By removing and remixing the putty, you are sending all that wood dust in the interior of the putty. The second time around, the putty makes direct contact with clean wood and gives you a perfect seal.
   5) Now, you want to make sure that the window looks good. The shape of the glazing compound that you just applied will yield a beautiful or an ugly window. Pickup the window and have it stand vertically. Have the interior of the window face you. Look straight at the glass. If you can see any glazing compound, then you have applied too much. The bottom line is that you must use a flat object to press down on the glazing compound and slope it just like the hypotenuse of a triangle.

5. I have used one and a half inch wide strips of glass for that job. Some strips were as long as the smallest inner window frame, and some were 10 inches long. You can use the shinny part of a ceramic tile. You will need to lubricate the glazing compound shapers with water if you do not want them to stick to the putty. Frequently look through the window from the inside to make sure that the gazing compound does not extend beyond the interior molding. From inside the room, the glazing compound should simply be invisible. Once you seal each pane of glass, you need to clean the glass immediately to remove all the fingerprints that are made of glazing compound residue. If you let them dry up for a day, these fingerprints could stay permanently. The best way to remove the glazing compound residue is to cut lots of small (2 or 3 inch) squares of paper towel in advance. Fold these square pieces a few times until you obtain a rigid pointy tip. That rigid pointy paper towel tip will allow you to clean one of two inches on the border where the glazing compound meets the glass. You can unfold and refold these squares once to obtain a second pointy rigid tip that is made of clean paper. Use each paper square once or twice and discard it. Once you clean around the border, you can clean the interior of the glass easily.

6. 6) Now that it is clean, I would let it dry for a day before painting. I usually stand the window up in order to paint over the glazing compound area. I paint all the lower horizontal parts of the frame then rotate the frame to position unpainted parts horizontally I use a small foam brush and paint as close to the glass as possible. In order to avoid painting the glass, leave a strip of unpainted glazing compound that is 1/16 of an inch wide near the glass. If you try to completely cover the glazing compound you will be spending a lot of time wiping out wet paint from the glass, or will end up having exterior paint showing when looking from inside. The good news is that assuming that no glazing compound is showing, you will be able to scrape off excess dry exterior paint.
   7) Before reinstalling the window scrape off all paint buildups inside the window track. Clean the tracks to make sure that it is not too narrow for the newly painted window. I sometimes use some lubrication on the very top to make sure that the top window does not get stuck. I also slide all the windows up and down once a week for a month until the paint is bone dry. Usually the windows get painted and the frame also gets painted, increasing the possibility of paint jams.

Tips & Warnings

• Do not try this on the kitchen table. Try it in the garage or pay the piper. As you can see, This could take some time. If you choose to have it done by the pros, they will also be capable of duplicating the molding in a wood shop. But, they also use epoxy extensively. I wrote this piece to help those who want to tackle the job by themselves. When my wife told me about her retired friend who had to go back to work just to pay for windows restoration at her house, I was not surprised. It took me three days or longer to rebuild a set of fancy windows.
• Always clean the surface of the working table with a brush or a broom. do not use your hand because small invisible pieces of glass will puncture your skin and could be difficult to remove.

[cherold598]

on 9/12/2009 Great tips for rebuilding windows.