Can standard floor joists hold up to a 400-pound appliance?
We've been looking for a new, more powerful stove, but the ones we're interested in weigh about 400 pounds. Can the 2x10 floor joists in our 10-year-old Cape take this kind of weight?
— Sharon, East Kingston, NH
Tom Silva replies: Based on the age of the house, I'd guess that the floor should be strong enough. But in order to know for sure, I'd need more information: the spacing between the joists, how long they run between supports (their span), the wood species (assuming they're solid wood, not engineered lumber), and the thickness and type of subfloor.
If you have any doubts, or just don't want to take any chances, it's easy enough to reinforce the floor under the range from the basement. Use some dry 2x8 or 2x10 blocking held flat against the subfloor by 2x4 cleats nailed to the joists. Or, instead of 2x blocking, you could cut plywood strips off the 4-foot edge of a ¾-inch sheet, then glue them to the bottom of the subfloor before you nail on the cleats.