Cupping wood floors

10 years ago

I live in a suburb of chicago in a ranch house. Our bedrooms are on a concrete base and the rest of the house is right above the basement. We had wooden floors installed in March, when it was still very cold and dry - oak, 3.75" wide. The installer did not put a moisture barrier between the concrete and the plywood. Spring and summer this year had a lot of rain. By the start of summer the floors in the bedroom (on top of concrete slab) started cupping and by the end it was very aggravated. In the rest of the house, the floors are fine. Once we started running the heaters and the moisture levels dropped the floors have started flattening out a little. Our original installer has offered to sand and refinish the floors again - and he wants to do in the first week of Dec. I am not sure if that's the right timing and if it will help at all other than a few months of flat floors. Does anyone have any advise ?

Sort by:Oldest

Comments (4)

User
10 years ago
1) Have someone with a high quality moisture meter (the type that makes little holes in the floor) check the moisture in several locations, in the wood floor (top and bottom of the boards) and in the subfloor. There's no point in refinishing the floor if the moisture is alarmingly high. If your installer doesn't have a decent meter you might have to track down a certified floor inspector.
2) I generally recommend waiting until floors have gone through an entire year of seasonal changes before refinishing.
gregmills_gw
10 years ago
Its good that ur guy is willing to make things right but i agree to let the floor wait a bit before resanding.
Related Professionals
Alpine Flooring Contractors · Anaheim Flooring Contractors · Chalmette Flooring Contractors · Chelsea Flooring Contractors · East Haven Flooring Contractors · Lathrop Flooring Contractors · Palm Valley Flooring Contractors · Pearland Flooring Contractors · San Jose Flooring Contractors · Temple Terrace Flooring Contractors · Mitchellville Carpet Dealers · Cumberland General Contractors · Leavenworth General Contractors · Norman General Contractors · Syosset General Contractors
lazy_gardens
10 years ago
Sanding and refinishing will NOT fix the problem. There should have been a moisture barrier between the concrete slab and the flooring. Sanding and refinishing doesn't make this moisture barrier magically appear under the floor.

Tell him he needs to take the floor out and install it properly, replacing any boards he damages. He needs to start with the kind of moisture barrier specified by the manufacturer, then do the rest of the floor.

He's supposed to be a professional! He should know how to handle concrete slab flooring.
glennsfc
10 years ago
There obviously is a moisture problem and a difference in the relative humidity levels above and below the wood planks. I have been working to convince the trustees of a church to rip out their 80 year old floor and properly prepare the slab underneath and install new. Their oak strip floor cups whenever it rains. However, sometimes people are like horses...you can lead them to water, but you can't make them drink.

A floor such as the one here may be alright if resanded, but probably not. Although I have never had moisture compromised floor planks 'crown' after refinishing...I have seen it and that is a possibility. Doesn't look worse than cupping though; at least it feels smoother when walked on.