What service should we get to handle this issue?

Question

We have a townhouse in FL currently rented out. Last weekend, the tenant sent me a few text messages for concern of mold in the house.

Back in January, we have had the downstairs half bath toilet clogged once, and some water overflew but not too bad. We had the pergo laminate wood floor in the adjacent living room. Water was removed quickly, and didn't cause any damage at the time.

Fast forward to last weekend. Tenant reported that the pergo floor next to the half bath started to 'bow' a bit, and it has been getting more obvious over the last few weeks. It is still not bad, but getting noticeable. ALSO, they noticed there are some spots (grey-light brownish) showing up on the downstairs AC vent covers. The spots are not there on the inside of the vent covers, nor anywhere on the upstairs vent covers. They are concerned if it may be mold, so reported to us.

Given the fact that it has been almost 10 months since the water overflow issue, I can't imagine the bowing of the floor and the spots on the vent cover are from the moisture back then. But have got no other leads. What would be the best service person we should get to take a look? A mold guy?

Sophia Wang · Answer

Thanks so much, Matt and Luis!

Luis A. · Answer

I agree with Matt on the AC vent. It could be a combination of both dirt and mold. The mold can easily form from condensation from high humidity and also which direction the air is blowing. If this is an adjustable AC vent and it is slightly closed the air might be restricted and allowing condensation to form right on the grille. I had this problem and once I opened up the vent to allow full air flow the condensation went away.

All this should require is taking out the grill, giving it a good thorough cleaning and installing again and make sure it's completely open.

Matt Devincenzo · Answer

Sophia Wang I'm from FL originally and I've seen something similar to both of your issues.

The "mold" looks like it is more likely dirt and dust coming out of the register when the air is on, and due to the humidity in FL sometimes you'll get condensation on the metal register(metal gets and stays colder than everything else and small amnts of condensation form) and then the dust sticks to it. Most likely the filter needs to be replaced and that will cause the unit to run more efficiently and remove moisture better as well as remove more of the dust from the air.

The floor is wood floor going to the bathroom, I've seen buckle before when the install was done too close to the bathroom tile and not enough of an expansion gap was left. The wood will expand(esp if over concrete, which is common in FL with slab on grade foundations, since it gets a little moisture coming up through it) and the expansion gap wasn't large enough so when it presses up against something it buckles in the easiest direction: up and away from the tile. The solution for my rental was remove the transition strip between the two and cut the floor back about 1/4"-1/2" and reinstall the transition. Once the floor has the necessary expansion room needed it stops buckling.

In mine, on the one bathroom that was enough the other had buckled worse and I had to remove about a foot of the flooring just so I could reglue it down but otherwise the overall solution was the same as above.

Hope that's all it is as easy as that.

Sophia Wang · Answer

Thanks John!

Just figured out how to post image.

The Air Vent: (The thing that confuses me is that it is only on the outside, not inside. I would imagine if it is from the duct, it should show up on the inside first. )

Floor: (it is actually not too obvious. I got the images from the tenants, so will have to have my handyman to come out and check on it)

This second photo indicates up to her finger tip the floor is bending up.

John Espinosa · Answer

Consider calling your HVAC specialist and have them inspect the coils and ductwork of your cooling unit. Im guessing you have a heatpump in this rental. Florida can get up to 50% humidity up to 6 months a year, so there is a good chance moisture can build up.

Depending on the type of ductwork you have, some materials are more indusive for mold growth.

As for the floor, im not sure. Any pictures perhaps?