Q. We live in an underground home and need your advice. We bought this home six years ago and bravely undertook a gut renovation, out to the concrete walls and down to the sand. We were too ignorant (and romantic) to think we couldn’t pull this renovation off, so we did. We are very happy with the results, except for one issue: sound control. When the floor was laid, we installed radiant heat and then poured a polished-concrete floor. The great room is 28 by 28 feet, capped by a concrete dome with a large central oculus skylight. We have drywall over the concrete walls. We think the concrete floors under the dome are behind the noise problem. The sound of our grandchildren playing or people talking fills the space. We might add new flooring, but we absolutely want to preserve the radiant heat. Would bamboo flooring be a good choice? Or cork? Ants have found their way into the house where the expansion joints in the floor have failed. How impermeable do we need to make the underfloor before adding new flooring? Is there a particular kind of expert who deals with these materials?
A.S. & C.N.
A. This sounds like a very interesting house with very unique challenges. First, I would be concerned with the ants. Once they have established a foothold under the slab, it could be an issue getting rid of them. I would use a urethane caulk made for expansion joints to seal things up, and then call an exterminator. A good program may be to have the perimeter of the house sprayed once a year.
Regarding noise control, anything to absorb the sound generated instead of it reverberating back will help. Rugs in select areas that cover enough of the floor would do better than any type of wood floor. If you do opt to cover the floor completely to mitigate sound, cork or vinyl-plank floors are better than solid wood, which is thicker and will prevent the heat from radiating through. You would have to be mindful to keep the floor around 80 degrees, but no higher. Radiant heat is rarely set that high, so it should not be an issue.
Mark Philben is the project development manager at Charlie Allen Renovations in Cambridge. Send your questions to [email protected]. Questions are subject to editing. Subscribe to the Globe’s free real estate newsletter — our weekly digest on buying, selling, and design — at pages.email.bostonglobe.com/AddressSignUp. Follow us on Facebook, Instagram, and Twitter @globehomes.