Summer is an eagerly anticipated time, but the season is not without its frustrations. In addition to the mosquitoes and sometimes oppressive heat, homeowners often find that a wooden door will no longer open or close properly.

High humidity will cause these doors to absorb moisture and swell. If the door is not properly sized or the hinges have loosened over time, the door may become stuck in its jamb or fail to close tightly.

A few simple steps can often resolve the issue of a sticking door. If the problem persists, you may have to remove the door and trim it down to size.

When humidity is the root cause of the problem, you can often unstick a door by bringing down humidity levels in your home. The home improvement professional Bob Vila says a hygrometer will let you measure moisture levels and determine if they are particularly high. Wet basements, poor ventilation in the kitchen or bathroom, and even a large number of houseplants can all produce a lot of humidity. Addressing these issues or using a dehumidifier might bring moisture levels down enough to get the door back in line.

Over the course of countless openings and closings, the hinges of a door can gradually become loose. Tightening them might be enough to put them back into alignment and bring the door back to its proper fit. The magazine Family Handyman recommends tightening screws with a screwdriver instead of a drill, since the power tool can strip the screw or its hole.

If the screw is stripped, you can replace it with a longer one. Three-inch screws, or screws that are about an inch longer than the current ones, will usually work well.

Longer screws can also help draw the hinge in and adjust the door placement. Replace the central screw on the hinge, drawing in the top hinge if the door is sticking near the top and the bottom one if it is sticking at that end. If the door rubs against the side of the jamb, you can draw in all of the hinges.

The jamb can also be drawn in, although this is a more laborious process. You'll need to drive a screw or two into the jamb near the center of the area where the door is rubbing. This will pull the jamb closer to the wall framing, but will also leave screw holes that need to be plugged.

When the screw hole is stripped, you can plug it with new wood to provide more purchase for a new screw. Rebecca Zacks, writing for This Old House, says you can fit a splinter of scrap wood into the hole. Use wood glue on both this piece of wood and in the screw hole; once it has dried, it will provide a reinforced surface in which you can fasten a screw.

Check to see if the door's weatherstripping is causing the door to stick. Amy Howell Hirt, writing for the National Association of Realtors' home improvement site HouseLogic, says weatherstripping installed to keep out wintry drafts may need to be removed or adjusted in the summer.

If the simpler fixes don't work, you can trim down the size of the door. This process is more involved, since you'll need to remove the door from the frame to work on it.

Find out where the door is sticking. Vila says there should be about one-eighth of an inch of space between the door and the jamb, roughly equal to the width of a nickel. You can mark where the door hits the jamb using a pencil or compass.

After the door has been removed, trim off enough of the edge to make it fit properly. Family Handyman says this process can be accomplished with a belt sander or planer. Use sandpaper to get down to the demarcated line and to smooth out any rough edges.

Be cautious when planing or sanding the door. Zacks says a considerable gap can be left when the door shrinks in the colder months, making your home draftier.

Add paint or finish as quickly as possible after you have gotten the door to the size you want it to be. If you skip or delay this process, the exposed wood can soak up more humidity and expand once again.

Rehang the door once it is ready. Vila says it may not be perfect after the first try, and that you may need to do some more sanding before it fits correctly.

If controlling the humidity, adjusting the hinges, or trimming the door don't work, the issue might be stemming from your foundation. A settling foundation can put more pressure on your doors, making them harder to close.