If your house has old, double-hung wood windows, chances are some of them don't operate anymore. Or at least don't operate well.
Double sashes have a surprising number of parts, and when something goes wrong with any one of them, the window becomes a wall you can see through.
Some of the problem areas:
* Missing cords, chains, pulleys or weights that mean the sashes won't open or won't stay open.
* Broken or missing parting beads (the strips of wood separating the two sashes) that mean there's no definite track for the window to travel.
* Paint or dirt buildups that make the sashes stick or make them difficult to operate.
L * Missing or inadequate weatherstripping that allows drafts.
* Swelling from water damage or humidity that makes the sashes fit too tightly in their tracks.
* Excessive wear or damage that leaves sashes uneven or weak.
* Gaps (from weather damage, warping or wear) that allow drafts, or make the sash "out of square" so it doesn't fit properly.
Of course, if you have problems with lead paint contamination, you'll probably have to get a certified professional to deal with the windows. But if you don't have a lead problem, you can probably diagnose the trouble and repair it yourself.
Despite the array, most of the ills can be cured fairly simply. It may be a nuisance, but it won't be hard.
Sash-cord problems certainly fall into this category.
Most old double-hung windows have cords or chains attached to the sashes that run through pulleys at the top of the jamb and fasten onto weights inside the window frame.
We say "most" have cords or chains because in some cases, builders got lazy or saved money on the top floors of a structure and didn't install pulleys and weights. Instead, they fixed the top sash and attached wooden wedges to the inside stop, which could be flipped out to hold the bottom sash up.
If your windows never had weights and pulleys, you'll have to live with the old system or install new sash channels that operate by providing tension on the sashes.
If your windows used to have pulleys and weights, but the cord has long since broken, the weights are probably residing inside the bottom of the jamb. You can fish them out and reinstall them. If they're missing, you may be able to find replacements at an old-fashioned hardware store, a salvage place or junk store.
First you have to get the sashes out. Remove them from the inside by taking out one inside stop and swinging the sash out. Then pull the sash out of the other side.
If a cord or chain is still connected, fasten it at the pulley with a nail or knot so the weight doesn't fall down inside the jamb and take the cord with it. Loosen the cord or chain from the sash -- usually it's nailed or screwed at the bottom the groove along the side -- and the sash will be free.
To remove the top sash, take out one parting bead. (Be careful with the parting bead. If you break it, it may be hard to get an exact replacement.) Then swing the sash out, pull it away from the other side, secure any still-connected cords or chains at the pulley and detach them from the sash groove.
If you're replacing the cords or chains and weights, you need access to the inside of the jamb. Some old windows have "pockets," or small panels in the bottom of the jamb that can be removed to get to the weights. The panels may be painted over. Use a chisel or utility knife to probe around for them. If you find panels, you'll need to break the paint film to get them out. They may also be nailed or screwed in.
Once you have the panels open, you may be able to simply lift the weight out, untie the old cord or chain and fasten a new chain to it. (If you're not so lucky, you may have to fish for it.) If you feed the chain over the pulley, it should fall far enough to reach through the pocket. (Cords are so fragile that chains are the only sensible replacement.)
Getting the new chain the right length may be somewhat tricky. If you have an old cord or chain to measure, that's great. But often all you'll have is a piece. On the bottom sash, the weight should be close to the pulley when the window is down (so when you raise it the weight will travel almost to the bottom of the channel. If it hits the bottom, there'll be no tension on the chain and the sash won't stay up. Also, you'd be raising the sashes' weight against gravity, without the counterbalance of the weight inside the jamb.)
On the top sash, the weight should be near the bottom -- but not at the bottom -- so when the sash is lowered, the weight travels up to the pulley. If the top sashes' chain is too short, the sash won't go down all the way. If the chain is too long, the top sash won't be held tightly against the top of the jamb.