My husband and I are in the process of buying a home and had the inspection yesterday. Most of the main floor is a hardwood flooring, but the inspector noticed it is wavy- I guess that may be called cupping. He said it was from moisture and didn't seem overly concerned (but it is not his money). Any advice on what to do now? Have the crawl space moisture measured? ask the owner to fix/remove and reinstall? Run? Do cupped floors ever un-cup if the moisture problem is fixed? Any insights would be greatly appreciated, we need to make a decision soon. Thanks, KH

If its a new house it was more likely fast building with no hvac up before install situation. Id still check under the crawl space and check for signs of excessive moisture. Some cupping in wide planks is normal and expected, hard to qualify "normal" without knowing if it is permanent of seasonal movement. Id have a flooring contractor with a moisture meter go and inspect the floor both above and below. If its bad it wont go away and is a reason to start some negotiations. Have the flooring contractor to give you a bid on the repair.

This depends on type of floor, subfloor and cause of moisture. I agree, I'd have a flooring contractor look at it.

If it's solid hardwood on top of plywood, it's probably no problem and can be sanded and refinished to get rid of most of the cupping and there may be some areas that need wood replacement....that is, if it's not an ongoing moisture issue and it was a one time thing.

On the flip side, if there is water or moisture coming from below this could be a serious issue and could mean full replacement as well as other issues. Of if it's engineered hardwood, it may need to be replaced.

I had a customers several months ago that brought me in due to cupping. House was built on a slab, never properly sealed and installed incorrectly on 1/2 plywood. Floors and subfloor needed to be replaced and concrete sealed. The buyer and real estate agent built that into the offer price. I think they took $20-$30,000 off to account for this.

Debbie Gartner aka The Flooring Girl
http://TheFlooringGirl.com
Westchester County NY

Depends, is the cupped appearance caused from edge compression(installed too dry), or a moisture gradient. The inspector said "caused by moisture" Did he document how much moisture?

Or did he say could be moisture?

A compressed floor can be sanded, but a moisture gradient has to be remedied.

How long has this home sat, unoccupied while being on the market?


The only way you are going to know, is buy a good pin type wood moisture meter, or hire a inspector that specializes in wood flooring.

Crawl space fixing can be complicated and depending who you use and if they think overkill is the best option, costly.

Conditioning the crawl space is also an option.

Why buy other peoples problems? Walk away.

Sounds like something to walk away from .it's possible that sanding and re finishing will solve the problem but I can't gauge that without testing the RH above and below the flooring as well as testing the sub floor for moisture content.

Keep in mind that sanding a cupped floor takes a lot of life off the floor because you are removing a lot of material from the edges before they get flat again.

Also very possible that someone used a steam cleaner on the floors trying to salvage their appearance instead of paying for an outright sanding or recoating. Never underestimate the cheap measures people will go through to "save money".