Doing away with the grate can increase the efficiency of a fireplace

Q My husband insists on putting a three-foot log on top of a fireplace grate, then lighting a fire with kindling beneath it. Eventually the log catches fire. He says he believes that if he builds the fire on top of the grate, more heat would go up the chimney. What is the proper way to build a fire in a fireplace?

A reader Los Angeles

We got in touch with a specialty house called the Fireplace of Bend, located in Bend, Ore. The company says that no grate is the greatest way to go, adding that a grate induces inefficiency, which results in higher wood consumption. Reason: more air gets to the burning wood.

The fireplace expert goes on: ''Begin with about one inch of ashes on the fireplace floor. Build up the fire directly on the ash bed. This way less air goes under the wood and less heat goes up the chimney. Don't clean all the ashes out of the fireplace.''

We are told that the manual of the Vermont Castings Company, Randolph, Vt., recommends that no grates be used in its wood stoves. That's enough for me. The next time I build a fire in my own fireplace, I'll opt for the no-grate method.

Q I need more light, not ventilation, beside my desk. A high, narrow opaque fixed window is insufficient, and a louver window replacement involves both security and appearance problems. Would glass blocks be the answer?

Marion T. Bryant Oceanside, Calif.

Glass bricks or blocks, which come in various sizes and transparencies, may just be your answer.

Check your Yellow Pages under ''mason contractors.'' Look for a reliable masonry contractor in your area and give him a call. Make sure that the mason who installs the glass brick is experienced in that line. Either he or a friendly carpenter can remove existing glass and prepare the opening to accommodate glass brick.

If you have a question on designing, improving, or maintaining your home, send it to the real estate editor, The Christian Science Monitor, One Norway Street, Boston, Mass. 02115. Forrest M. Holly is a longtime California builder now living in southern Arizona.