ArcaMax

Dear James: Our old wooden back door is worn out from years of kids and pets. What is the best way to replace the door on a house which has aluminum siding? -- Cory K.

Dear Cory: Replacing an old exterior door is a weekend project most DIYers can handle. Installing a more durable insulated steel door might be a good choice if it still gets abuse from your children and pets. Make sure to select a door that also has durable magnetic weatherstripping.

Starting with a prehung door, which is already mounted to the side and head trim of the door (called a jamb) is probably your best bet. This eliminates steps of fitting the hinges and squaring the door which are often beyond the skill level of many do-it-yourselfers. Some prehung doors already have a threshold along the bottom.

First you have to remove the old door and its jambs, and you may have to make a new rough opening if your new door is larger. To remove your old door, take it off the hinges. Remove both sides of the door casing. With a reciprocating saw, cut through the nails that hold the jambs. If there is a threshold plate, cut it loose, too.

After the rough opening is ready, test fit the new door by centering it in the rough opening. The door is heavy, so you will probably need assistance for this. Be sure the door is plumb. It is important to maintain even spacing between the jamb and the door.

Next, trace the outline of the molding onto your siding. The molding is a milled trim piece that covers the gap between the frame and exterior finish. Remember, if your siding is vinyl or metal, enlarge the outline to make room for the extra trim these types of siding require for a professional, finished look.

Cut the siding along your outline using a circular saw. Set the depth of the cut on the saw so that it does not cut into the sheathing. To prevent damage to the siding, finish the cuts at the corners with a sharp wood chisel instead of trying to use the saw.

Slide 8-inch wide strips of building paper between the siding and the sheathing at the tops and sides of the opening. Bend the paper around the framing members and staple it in place. This will shield them from moisture.

Apply several layers of silicone caulk to the subfloor at the bottom of the door opening and over the building paper on the front edges of the jack studs and header.

Center your door in the rough opening and push the molding tight against the sheathing. From inside, place pairs of wood-wedge shims together to form adjustable flat shims. Also insert shims into the gaps between the jambs and framing members and at the lockset and hinges every 12 inches around the jambs. Fill in any other gaps with loosely packed fiberglass insulation.

Check again to make sure your door is centered and then nail it in place. When you are finally finished, send the kids to play at the park!

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Send your questions to Here's How, 6906 Royalgreen Dr., Cincinnati, Ohio, 45244 or visit www.dulley.com. To find out more about James Dulley and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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