Floors making a cracking/popping sound

Q: We have Bruce hardwood floors in the downstairs. The house is about 4 years old. When you walk on the floors they make a cracking/popping sound. I heard the hardwood floors popping somewhat from day one, but it is really bad now. Is there any way to fix this problem? Just wondering if the floor is too tight or uneven?

A: Since I don’t know if the floor was nailed down well and what the sub floor is, my best guess is that it is likely environmental. This time of year the furnace goes on and with generally lower humidity levels in the house some contraction will likely occur. Especially if the milling of the tongue and groove happened to be very tight you could get a popping sound from the pressure the board is under as it pulls slightly away from the matching rows. I would check the relative humidity in the home with a hygrometer (you can buy an inexpensive one at most electronics stores) and try to maintain RH in winter between 35-40%. You don’t want it to drop below 30.

Related Q: My tongue and groove flooring makes a popping sound in certain spots. The boards seem to have warped in some areas to the point the floor looks raised. These type of noises didn’t happen before, when I had carpet on the floor, even though there was no padding underneath.

A: It would appear your floor is under pressure from expansion of the boards. The only thing that can cause this is excess moisture in the wood. You either have a leak somewhere or extremely high humidity. You can check humidity with an inexpensive hygrometer. A dehumidifier may help.

Similar Q: We have an 11 month old home in Ohio. Our pre-finished oak hardwood floors pop and crack when we walk on them. We had the builder out, and they placed some nails in the seams of the worst areas, but it seems to have made it worse. This is a problem during all seasons, not just when the humidity is higher or lower. Is this the nature of the product or is there a flaw in the installation?

A: I could only make a guess at this point, not knowing what the floor was installed on top of. This can be important because some types of sub flooring material do not do a good job of holding nails well. It may well be the case here. Also, if not enough nails were used and there is a small dip in the sub floor, walking over that spot can cause some flex. This is particularly important near board ends. There is suppose to be a nail not more than 3 inches from the ends of each board.