How to: spot repair of painted chipboard flooring

[LilyWai]

When I bought my current home the flooring was painted grey and looked fine but as I have dogs as soon as Winter came and I had muddy dogs padding around the house I realised what material the paint was covering - chipboard.
As soon as I tried to wash it I noticed the paint was starting to slough off on my mop and after a few areas around the dog's water bowl got wet disaster struck and the chipboard swelled resulting in several circular areas - the largest is about 2 inches across & several smaller spots as well - of damaged chipboard.
The same thing has occurred in areas in the bathroom too where shower water over time has caused spot damage resulting in swelling and parting of the chipboard material.
I have had to stop washing the floor as it was just making it worse and when you have two Labradors you REALLY need to be able to wash the floors!

In lieu of full house replacement of all the flooring I am hoping their is some way to spot repair the small damaged areas, repaint all the flooring and covering it with a good strong coat of polyurethane to seal.

What would be a good option for DIY repair of these damaged areas? Wood putty has been mentioned but I'm not sure how hard wearing it is for flooring & whether you can paint over it?

**Attached is a photo of the damaged areas.

 

[freddiemercurystwin]

Cut out the damaged areas and replace with new board, then put vinyl down over the floor.

 

[foxhole]

You need to change the flooring, painted chipboard is unsuitable flooring in any situation. Certainly totally unsuitable for washing.

 

[Deleted member 174758]

Chipboard? WTF? Chipboard is fine for a sub floor and is used in millions of houses and commercial buildings, but it always requires a flooring material (e.g. vinyl, carpet, tiles, laminate, etc) to be fitted. Never heard of anyone simply painting it before

If the raised areas aren't too soft you might get away with power sanding them back and treating them with wood hardener before covering them with a more suitable finish flooring. Other than that it's case of cut out replace, then cover. Pity the builder didn't use a better grade of chipboard, though. Stuff like P5 chipboard isn't affected that way (although still not suitable as finished flooring no matter what you paint it with)