Water Damage from Renter, who's responsible?

[Joel C.]

So here is the situation...

On October 1st my tenant mentioned their washer (purchased by them) was leaking and that there was major warping in the downstairs bathroom (also the washer/dryer room), bedroom, and hallway. When they brought this to my attention they told me water would leak from the ground every time there was heavy rain. I had a contractor come out and take a look and he could not find any issues, plus the tenant's unit is on 2 feet of concrete slab so I doubt that is the issue. I suggested the tenant get a second opinion since they could be liable for damages. The tenant never received a second opinion and when they moved out in the beginning of January I replaced the floor and sent the tenant the remaining portion of his security deposit with an itemized bill of work.

Here's what I know.

1. The tenant didn't report the issue immediately because the floors had already been warped.

2. The tenant had the option to get a second opinion but didn't get one. The tenant told me their washer was leaking a month before (September), and I informed him the washer is his responsibility and he must replace it.

3. After the tenant left I had a plumber come out to see what might have caused the damage. He did mention there was a slight drip in one of the valves but it could not have caused that much water damage.

Here's my question, ultimately who is responsible for paying the damages?

Thanks for your help.