Some ideas on how to mouseproof house

Is there any insulation that is mouseproof? In dismantling buildings I find that mice have cleared large areas of studwall insulation and packed it along the sill to make nests. The type of insulation was either wood or glass wool. Since I am now reassembling one of the buildings I would appreciate knowing of a mouseproof insulation product.

Ray Ferriss Ilion, N.Y.

Inorganic insulation as animal food is, of course, not in this picture. Untreated organic insulation may feed mice, but such material is not commercially usual.

By all means use an inorganic or properly treated organic insulation in the reassembly of that old building.

Mouseproof? That term falls into the same category as fireproof. Almost anything will burn if it's heated enough. Mice can gain access into just about any building by one way or another. A mouse-resistant structure may be a better term.

How do you make a building rodent-resistant? Not so much in the use of any particular insulation as in inhibiting rodent access to the structure.

Do not leave any holes or cracks for mice or rat ingress. Provide escutcheons at all pipe piercings of the walls, ceilings, roof, and floor. Pipes in oversized holes penetrating the structure otherwise may provide entry for rodents.

Undoubtedly there are tricks of the trade known by pest-control operators to prevent of rodents from entering attics, walls, and below floors. Have a talk with a veteran pest-control operator. He may deal you some interesting permanent prevention cards on your specific rehab.

I plan to coin a new phrase concerning mouseproofing, to wit: ''An ounce of mouse prevention is better than a pound of pest cure.'' Remember, you read it first in ''Ask a builder.''