mold that smells of ammonia/cat pee smell?

[redbopeep]

OK, I haven't "seen" a mold causing this...but can smell ammonia/cat pee strongly where some Meranti marine plywood (BS1088 btw...) used as a subfloor has gotten wet. The two different places both got wet when we had quite a bit of rain and hatches were open. In both cases soaked and in both cases strong cat pee smell immediately. One place the plywood has a synthetic tile on top of it (bedded with a silicone sealant) and the other place the plywood is sealed with Smith's CPES but the top material (some teak) hasn't been installed over it.

So...I know that ammonia smell as we've owned cats but I also know my own cat never had any opportunities to anoint these particular locations and he died about a year ago.

I also suspect a mold because last year (cat already passed) we had a smell of ammonia in some bedding and clothes (that we hadn't used) and I ended up doing lots of laundry to make sure the smell was gone. With no cat in the boat, it was a real mystery and now this "new" smell is also a mystery.

Any clues? Appreciate anyone with similar experience letting me in on what this could be.

[Bob Smalser]

Dunno about Meranti, but there are no shortage of woods with unpleasant aromas. Yellow Cedar smells musty, and both holly and boxwood smell as you describe....like urine.

I also recently visited a renovation jobsite having OSB subfoors that were badly stained with what must have been dried-up pet urine, because after an hour of steaming wallpaper, the ammonia and formaldehyde fumes (from all that phenol glue) were most impressive.

[MiddleAgesMan]

I wouldn't assume mold. Could be the meranti or one of its adhesive's chemical components. Might be the silcone you used to bed the tile. Might be the tile itself since you said it was some sort of synthetic material.

I'd say get it dried out and see if the smell goes away.

[Michael D. Storey]

Is there insulation under the sub? Insulation of the fiberglass variety can often smell like that

[redbopeep]

No insulation and the smell is already going away as the wood is drying up. It is still damp in the location where there is just the plywood and it smells more than the location where the tile is. The tile location only smells in one spot where I had a small bucket sitting and it was wet under the bucket. Wet wood=smelly. We have used the exact same Meranti plywood in a variety of places and none of the other stuff stinks when it gets wet though. We are beginning to wonder if one of the boatyard cats could have pee-ed on some of the plywood or somethings...a real mystery.

[Ian McColgin]

Sounds like the urethra breakdown of the plywood's formaldahyde glue deteriorating - or whatever that chemistry is. I've seen and smelled it before. It's possible that the CPES not getting everywhere actually accelerated this.

[Jay Greer]

I agree with Ian on this one. Urea resin glue is most likely the cause. One wood that smells like urine is that which is known as "Piss Elm". It is nasty smelling stuff when cut on on a table saw or routed!
Jay

[redbopeep]

Considering that in both cases it is really "built in" to the boat, should I just dry it out as best as possible and add CPES to the area that doesn't have a covering and...humm...seal up the seams better in the tiled area? Sorry I can't recall the name of the tile, it's not vinyl but anyway is similar but much stronger. I can remove the tile, seal, and reset new tiles. Hate to do that since I've got plenty of other things to do.

[Jay Greer]

You could hang up one of those automobile deoderizers that are shaped like a pine tree.
Sorry, I couldn't resist!

I think that the CPES after the wood is dried out is a plausable solution.
Jay

[Don Kurylko]

I'll go with the boatyard cat theory. Good plywood shouldn't breakdown that quickly. Dampness always seems to highten unpleasant odors - think of damp bath towels that have been left up a little too long. Yuk!