Swelling of laminated floorboards

Hi guys, my first post here.
The floorboards of our investment property started to swell around the edges all over the floor. The house is just one year old and the floor is still under warranty. A guy from the flooring company came for an inspection today and he straight away blamed the tenants for somehow letting the moisture getting underneath the boards. He was confident in saying that even if we get it inspected by the Australian Timer Flooring association they will come to the same conclusion.

But the tenants swear that they always dry mopped the floors and even used towels to wipe off any extra moisture immediately after mopping. And I trust the tenants as they take really good care of the property and always watch out for faults/issues. Moreover, the tenants are raising the question like why would you have such floorboards that swell/bubble even with careful mopping.

What should be my course of action in this circumstance? Thanks in advance.

The damage is not too bad yet. So, it's hard to show them in the photos. But I am worried they might get worse over time.

 

Mopping floors and leaving water will do that but its only on the short edges. Are these cut edges or as supplied eg is it just one board per "run" where its been trimmed ? Strange the length edges arent also affected....Its possible the board has a waterproofing but when its trimmed this is compromised at the cut edge. This issue occurs with undersides of doors and can cause curling on the lower door edges if the base isnt correctly sealed with the right (non water based) paint. Corinthian would knock back endless warranty complaints on that. If the base wasnt the same paint or sealer as both sides they would also knock it back.

 

It's moisture ingress and you always leave an expansion and contraction gap around the perimeter of your room. This gets covered with skirting

 

The flooring guy was saying the ATFA will charge me between $500-$800 for a visit?

 

So, should the tenants be responsible for the damage?

 

I would get a second opinion from another installer and then go from there, maybe straight to a solicitor but it looks like swelling from water to me.

 

If you're confident the tenant is not using excessive water on the floorboards it could possibly be a building defect with the slab i.e. slab edge dampness. If the footing is not adequately protected with a vapour barrier, moisture will be permeating through the slab causing damage to the flooring. I'm not sure if a membrane is required by the manufacturer for this particular product?

I would be inclined to get a Atfa rep out and have them check for dampness in the slab. This would be a building defect the builder needs to rectify under the home warranty.

 

This was my first thought. I think @vbplease is on the money.