Q: My house has old, wooden double-hung windows. Some are hard to open, while others are simply stuck. Are there people who can fix these, and is it worth it?

Potomac

A: Sometimes it’s fairly easy to get stubborn, old double-hung windows to operate smoothly. Other times, it can be pricey but worth it, especially if you live in an older house where replacing the windows with ones that look the same can be expensive.

Easiest to fix are windows that operated correctly until a recent paint job. Wait for a day when the air is dry, because humid weather causes wood to swell. On each side of the window, run a sharp utility knife between the lower sash (the framed glass section that should move up and down) and the inside stop (the narrow trim piece alongside the sash). Then jiggle the sash along the top and bottom and see whether you can get the sash to move up.

If that doesn’t work, try cutting where the top and bottom sash meet to break any paint that has sealed the sashes shut there. You can also place a board underneath the top of the sash and gently tap on it; be careful not to hit the glass.

Next, try gently prying the sash from the outside. Place a wide putty knife or a thin piece of wood on the sill (the bottom piece of the window frame) to prevent dents, and gently pry upward using a thin-bladed tool, such as the Shark Eight-Inch Prybar and Nail Puller ($15.97 on Amazon). Work close to one side, then the other.

If the window still sticks, or if you can’t access the window from the outside, remove the inside stops. Cut through the paint between each stop and the adjoining window trim, then use the wide blade of the pry bar to loosen the wooden strip. Place a wide putty knife or a thin piece of wood under the pry bar to protect the window trim. Once the stops are out, you should be able to move the sash or determine where paint still sticks so you can cut through it.

Then you can decide whether a functioning lower sash suffices, or whether you also want to free the upper sash. To do that, remove the lower sash by disengaging the mechanism that allows it to move up and down — usually ropes with knots that fit into recesses on the sides. Work each knot out of the recess and hold on until the knot stops against the pulley at the top. Then, on at least one side of the window, remove the parting strip that separates the upper and lower sashes. The parting strip is a thin piece of wood that fits into a groove, so it isn’t easy to pry out. It might split, so be prepared to replace it with new wood.

Once you have removed both sashes, or just the lower one if you decide that’s enough, remove any nails you freed. Use diagonal pliers or crosscutting pliers; their curved blades grip the nail and act as a miniature pry bar. Then use a paint scraper to smooth off any paint crusts on the sash and surrounding framing. When you are working with old wooden windows, there is a high likelihood the paint contains lead. Family Handyman has safety tips , which you can find via a Google search for these two phrases: “how to remove lead paint safely” and “family handyman.”

Then put the window back together.

Or you can hire someone to do this for you. Search online for companies that specialize in wooden window repair, then call to make sure these companies are interested in repairing old windows, not just replacing them.

One option is Victor Faustino Handyman Services in Laytonsville, Md. (301-343-4090; victorfaustino.com). Owner Victor Faustino said it might take five minutes or an hour or two to free a window. He charges $120 for the first hour and $85 an hour thereafter.

Virginia Window Repair in Lorton, Va. (571-228-7551; vawindowrepair.com ), typically charges around $200 to repair old double-hung windows with steel weights that move up and down on ropes. But the owner, Alex Diany , said he is booked until December.

Color Alchemist Company in Glen Echo, Md. (202-679-5525; coloralchemist.com ), charges a flat $50 an hour, with a maximum per window of $3,600. That maximum is a hint that this company specializes in completely refurbishing old windows. John Learnard, the owner, said when he’s done, windows move up and down “with two fingers” and look gorgeous. His crew strips lead paint, replaces scratched glass, reglazes all glass panels, installs new, hidden weather stripping, and repaints the sash and trim using oil paint made by Fine Paints of Europe.

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