Dear James: Our home has real plaster walls. There seem to be quite a few cracks that need to be repaired. We were wondering if we should try to repair all the cracks or replace it all with drywall? -- Larry J.
Dear Larry: It is almost impossible to avoid cracks in a real plaster wall, but don't remove it and install drywall. This would be a substantial project and plaster is clearly superior to drywall. The only reason plaster is not used more today is its higher cost. If one's budget were unlimited when building a house, I would always recommend plaster walls.
Plaster is a much harder material than drywall, so when there is some movement in the underlying support structure, cracks may form. They often start at corners of windows and doors where there is the most movement from season to season.
Many of the cracks you repair will never crack again, but others will gradually reappear over time. This the nature of the hard plaster material and a small inconvenience for its benefits. If you ever have to remove wallpaper from a plaster wall, you can really soak it to remove it quickly. If you had drywall, the job would take three times longer.
Repairing cracks in plaster is somewhat similar to fixing them in drywall. First, make sure the wall structure is sound in areas where there are many cracks. Tap on the wall and you may be able to hear or feel if it does not seem to be well supported. Also, check for termites. I have seen them consume the sill plate on the foundation which allows the walls to sag.
Fiberglass drywall joint tape is good to use over the cracks. For fine cracks, this may provide enough support to eliminate any future cracking. Some of this tape has an adhesive coating to hold it in place while you are working on it. Once you get the feel of working with it, the adhesive-type will not be a great advantage.
Sand the area over the crack to slightly more than the width of the joint tape. This will give it a good surface to adhere and it will allow it to be recessed. I have seen it put directly over the crack, but when lamps are on at night, the shadow from the slight bulge may be apparent.
You will have several choices of drywall joint compound to use over the fiberglass tape. Premixed types are available in a small pail at most home center stores. This is easy to apply with a trowel (slightly wider than the tape) and to sand smooth with a sponge sanding block.
A better, more durable compound is a dry powder type that is used by professionals. It is available in several grades with different setting times. Professionals use fast-setting compound, but a slower-setting one may be better for you to try. If you have trouble finding it, contact these manufacturers: Georgia Pacific, (800) 284-5347, www.gp.com and or USG (800) 874-4869, www.usg.com.
Plan on applying several layers of drywall compound over the tape on the cracks. Work the first layer into the fiberglass so it adheres well. The next layers are just to add more strength and to smooth it out.
Send your questions to Here's How, 6906 Royalgreen Dr., Cincinnati, OH 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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