Repairing water damage to wood floor

[promark747]

Came home the other day and discovered a pool of water under the pedestal sink in my powder room.  Turns out the hot water supply valve had a leak.  I removed the sink and cleaned up the water, but I can tell there's been some seepage underneath the surrounding oak flooring, as the boards have started to cup slightly at the edges.  I would say the affected area is maybe 2' by 5'.  The floor (standard 3/4" thick oak planks) is unstained/natural and coated with a satin polyurethane.

I'd like to tackle this with my existing Festool sanders and was looking for advice on grits and methods.  I own the RO90, RS2E and RTS/DTS400.  Once the floor is sanded smooth, any tips for blending the new coats of poly into the surrounding areas without creating obvious lap marks?

Thanks!

 

[tiralie]

I would wait for it to dry out before I did anything.
This will take a while.
Then I would figure out whether I would need to sand to level or just re-coat.
Tim

 

[mouppe]

I think the main problem is underneath the boards and the cracks between them. I'd lift a couple of boards if possible to let the sub-floor beams etc. thoroughly dry out.

If the boards are cupped you may want to see if the cupping disappears after they have dried out before reaching for a sander.

 

[epicxt]

+1 on waiting. Had this happen about a year ago at my parents place (faulty hose fitting in the dishwasher) and it took 4-5 months to lay back down. Barely noticeable now and will just need a light leveling sanding and recoat of Osmo Polyx.

 

[Walk On Wood]

+1000 on waiting.  I see this all the time. The biggest mistake you can make is sanding before its dry, doing so mean the boards will crown when they dry out.  Wait til it's dry, it can take 3-6 months depending on what part of the country and what season.  You can also verify with a moisture meter.

If you're in a hurry, you can rip out the wet boards, let the subfloor dry out (it's much faster, maybe a week or so), reinstall new boards, and sand and finish.