Why more insulation over unused rooms?

Q. Our two-story, older-type house with full basement has R-19 attic insulation. All windows have storms. Where do we go from here? Do we add additional insulation in the attic even though we do not heat upstairs; or do we invest in wall insulation? We completele close off the upstairs rooms in the winter. Raymond Brocis Portland, Ore.

A. I wouldn't install any additional attic insulation over an unused second-story area. You wouldn't get any real benefit from it.

If the perimeter walls are stud-framed, then go to a reputable insulation contractor in your area and get a price to install exterior wall insulation. Will its cost give you sufficient insulation benefits to warrant the outlay? Your local utility company should be able to help you answer this question.

When the insulation contractor comes out to price the wall insulation, discuss with him the feasibility and cost of installing insulation between the joists that separate the heated first story and the unheated second story.

Again with the help of the utility company, compare the benefits with the cost.

You might also ask about the cost and expected benefit if you were to install insulation between the first-floor joists and the basement, assuming it, too, is unheated.

Of course, be sure to weatherstrip all windows and outside doors.