Bathroom musty smell - toilet sewage smell or crawlspace?

[Hiltxan]

I've always noticed a smell in the bathroom, I'm not sure if it's sewage smell or musty smell from the crawlspace from the base of the toilet.

I replaced the wax ring before. When I was replacing it, I noticed that the flange was rusty and broken, so I bought a kit from home depot and just installed it on top because I didn't want to replace the flange and metal. DANCO Perfect Seal Toilet Wax Ring with Bolts 10826X and the seal seems fine because I don't see any leak from the back of the toilet. Then I also caulked about 80% of the toilet, leaving 20% uncaulked in the back because I can't reach it. Before I caulked it I could always feel a draft from the base of the toilet. I still notice a musty smell in the bathroom whenever I first walk in.

Can the smell be coming from the crawl space? I have not noticed any leak whatsoever for the past 6 months from the back of the base of the toilet, but can it still be a small leak going between the subfloor and floor? Should I caulk all the way around the toilet then?

Thanks!

 

[Geofd]

Check your crawl space, I would also caulk the rest of you feel a draft, you just need to check the crawl space from time to time anyway

 

[Bird Doo Head]

Ventilate the crawl space?
Many building codes require it to prevent mold & bacterial growth and wood rot. (Most likely the source of the odor, since you ruled out a leak.)

If you fit in the crawl, maybe kill the existing mold that's causing the smell by spraying the wood with a quaternary ammonium. (Restaurant supply houses sell unscented & some of the Odo Ban products have it but stink of perfume for a few days.) If the water closet did leak onto your wood below, it will kill mold and all except a non-enveloped virus (rare) and clostridium difficile.

I also suggest a 6 mil vapor barrier on the ground & a foot or so up the walls. Check with the local building inspector or a good builder for recommendations about the vapor barrier & venting. (Depends on the climate where you live, I think.)

A fun afternoon project? Not so much, but neither is replacing rotted joists & sub floors (or getting sick).

Hope This Helps
Paul

 

[Hiltxan]

Crawl space is ventilated - it just smells like an underground basement or wine cellar, musty. I can crawl down to go check to make sure.

Is there anyway to test whether or not the odor is sewage? How likely is it that there's a leak around the wax ring (if I've never seen water come out from the base of the toilet)?

Thanks!

 

[Geofd]

You would see wet or damp spot in the dirt

 

[Hiltxan]

I tried to reach the place the other day in the crawlspace. I couldn't get to it (too many pipes, ducts blocking passageway).

The crawlspace didn't really have a smell and so the toilet smell is different than what I was smelling in the toilet. Is there anyway to tell if the smell is sewage from a detector (similar to how gas is detected with a digital meter/reader).

Also, now just debating if I should caulk the last 20% of the toilet towards the back, but want to make sure there is no leak I am missing. It's been close to a year without any signs of dampness or water that I can see in the bathroom. Thoughts?

 

[Twowaxhack]

Pour peppermint oil down the roof vent. Or have someone do it while you stay inside with all fans and ac turned off. Pour about $25.00 worth down the pipe followed by a quart of warm water.

 

[Mitchell-DIY-Guy]

What's the inside of the tank look like? Underside of the tank lid? I've seen some Nasty insides full of organic growth. Worth a cleaning if they show growth...