Ask an architect

March 8, 1985

Q We have just built a new home in an area where the woodpeckers are making holes in the siding and placing acorns in the holes. What can we apply to the wood to discourage the birds? A reader The only way I know to discourage these feisty characters is an owl. You can purchase ceramic or plastic owl statues through your local farm-supply dealer or catalog. Place it on a prominent perch on the eave or under the high point of the roof overhang. It should do the job.

Owls are also somewhat effective in keeping sea gulls from perching on your boat. Q Can you tell me something about the life cycle of the post and beam beetle and the best way to deal with them? I have tried surrounding the timbers of my log cabin with plastic and enclosing mothballs, but I don't know yet if that has worked.

Joe Hegarty

Mullica Hill, N.J.

You're dealing most likely with the powder-post beetle (Lyctidae). The adult beetles lay their eggs under the bark or in protected crevices in the wood. The larvae hatch and go into the pupa stage. The pupae chew their way into the wood and become adults, which, in turn, chew their way back out, pushing a ``powder post'' out as they progress.

The larger holes are where the adults have come out.

The treatment can vary with the severity of the infestation. The more extreme condition would require fumigation under a tarpaulin or tenting the entire structure.

A minor infestation could be controlled with the application of 5 percent lindane dissolved in a moderately volatile light oil, such as deodorized kerosene, at the rate of 1 gallon per 100 square feet. This may require repeated applications.

I would recommend using a commercially available insecticide that lists lyctid beetles on the label. To the real estate editor:

It's good to see the ``Ask a . . .'' column back again. Maybe I can add a bit of information regarding the job of resurfacing a basement floor, one of the questions appearing in the Feb. 1 issue.

The most cost-effective route for an interior slab depends on the overall levelness of the floor and the floor covering (if any) to be used.

If the floor is to be covered with carpet or roll vinyl, it may be sufficient to trowel or scree on something, such as Dependable Crack Filler (which, as far as I can tell, is simply plaster of Paris). At any rate, it is quite inexpensive. Work with small quantities, because it sets up fast. With larger holes, use a material called Deep Rock, made by the same company.

Alternatively, 4-by-8-foot sheets of plywood, laid over industrial adhesive, make a quick job. If the floor is less level, up to a three-quarter-inch sheet could be laid over thick beads of construction adhesive, which can be bought in standard caulking-type tubes.

Strip hardwood could be nailed directly to the three-quarter-inch subfloor, but if the floor is to be covered with parquet or used uncovered, a more durable material is needed. Then the expense of a latex topping mix is warranted. Go to a ceramic-tile supply store for the material.

The types found at building-supply places are far more expensive and harder to work with. The ceramic-tile supply store will carry a number of materials that need only to be mixed (rent a power mixer that goes in a big pail to get good results), poured on or troweled, and left to set. Again, work in small quantities and quickly.

You mention cleaning the slab. This is best done with a power floor-maintainer with sandpaper, wire brush, or grinding stones, depending on the amount of unsound material to be removed.

One last idea that may have an application for some people: If you plan to surface the floor with ceramic tile, nothing needs to be done at all, no matter how rough, loose, or uneven the surface is.

Spread a thick enough bed of fine sand to cover the irregularities, then lay the tile directly on the sand. Work in narrow strips. Then, using large plywood sheets for walking or kneeling on, grout the tile carefully to avoid shifting them. Believe it or not, as long as the edges of the floor are protected with wood sills, the floor stays sound.

If small tiles are used, they may not sit still while the grouting is being done. In this case (or if you are generally suspicious of the whole idea), mix dry portland cement with the sand (1 part cement to 6 parts sand) before laying the bed. After the tiles are down, lightly dampen the whole floor so the water seeps in and thoroughly wets the mixture underneath.

Give that a couple of days to set before grouting. You could drive a truck on it then.

Brian Zavitz

Toronto Q We wish to add a fireplace to our home which is on a raised foundation with a wood floor. We would like to do as little work as possible on the existing structure and prefer the look of used brick. Could you suggest something which will accomplish this project on a modest budget?

A reader

Use one of the many ``zero clearance,'' prefabricated metal fireplaces on the market which can be set directly on your wood floor, framed around, and brick veneered. The triple-walled metal flues and all of the pre-made caps and flashings make for easy installation.

Be sure the unit and the installation comply with local building codes. The cost of this type of installation can run to one-half to one-third the cost of a masonry fireplace.