Just bought a house, a reno job. Prior owners had put in a rather nice bathroom in the basement with a soaker jacuzzi tub but they botched the job and I’m having to do a tear out due to massive mold under the tub and in the wall adjoining the shower (due to improper sealing of joints).
When I opened up the wall I found that they had placed fiberglass insulation (the yellow stuff) around the tub and Im wondering why this might be. It wasn’t attached to anything, just placed between the exterior walls of the tub and the surround.
I’ve never seen this in any tub I’ve had (although I must admit to only ever having had one jacuzzi tub before and it was a very basic model).
Is this normal?
The tub is in a basement so maybe this has something to do with it? (The exterior walls are insulated, so this is extra).
Was it an attempt to keep the water warm longer?
Finally, after I clean it out, should I put insulation back in?
In order:
Not unheard of, though probably not universal.
Maybe, but I believe it’s not uncommon in any room. Most people like tub water above room temperature no matter what room.
Yes.
Your call. I don’t see any drawback, and might save a bit on hot water bills.
I was told by design engineer from Whirlpool that insulation provides sound deadening for appliances. The more expensive models of appliances are given longer life parts and more sound deadening features of which insulation is a big part. Some insulation is there to stop extreme heat transfer. It’s in appliances for noise reduction and regulation of heat loss. The specifics of this conversation where not on a jacuzzi, but something similar.
I don’t like having to keep replenishing the high temperature with additional hot water. There is alway fiberglass insulation left over from building a house and it can easily be disposed of under and around the tub/shower.
Capiche ?
The fiberglass insulation had nothing to do with your problem. If you like to soak hot as economically as possible, yes, replace the insulation.
Well my concern is whether or not I’ll have this much moisture collecting again.
I know the problem had nothing to do with the insulation, but I’m worried about a repeat of the mold if it leaks again (This problem seemed to come from slow seepage over long time. The insulation in this case acted like a wet sponge on the wooden frame).
Having said this, any suggestions as to what alternatives for insulation that WON’T act like a sponge?
Bathtubs are usually up against a wall. Could the insulation serve to reduce the chance of heat from the water causing the seams between boards to expand and contract? I can see that possibly causing minor structural damage over time.
A friend of mine who built his own house used polyurethane foam (spray-on) insulation on the backside of his tub. He swore it kept the water toasty warm for quite awhile. Also, I wouldn’t think the polyurethane would hold water like fiberglass batting.
As someone who has been involved in both boat construction and house construction, polyurethane foam and fiberglass batts, I’m telling you that regardless of the habitat you may be providing for mold, you need to direct your concerns towards the area of moisture ingress. Any confined space within a primarily wooden structure that is allowed to take on moisture without any drying cycles will rot and facilitate negative biology. Period.
Every tub/shower I’ve seen allows for wall exterior overlay and caulking. If this is not done thouroughly and properly, your bathroom will experience biological decay over the long haul. Regardless of insulation, you do not want to trap a hidden moisture environment in your home
If you like toasty long baths I’d suggest a cast iron tub(with someone else getting it in place) They hold heat much better. It is not unusual to see insulation around a tub. Like mentioned earlier it’s simply a good easy place to throw excess insulation and it might even have a possitive effect.
If you want to insulata around your tub intentionaly, I’d suggest polystyrean sheets. If you really want to pack it in there you could use ‘great stuff’ or similar. Jacuzzis use something similar to great stuff to fill in between the skirt and the tubs.
One further note. The Boston Whaler brand of boats are well known for the superior application of polyurethane foam. I’ve repaired fiberglass breaks in at least a hundred Boston whaler huills and every time I’m fighting moisture and the rotten smell of a septic tank.
Unfortunately the people that did this “upgrade” may not have thought this through completely.
The tub has nothing of the sort. It seems (to my untrained eye at least) to be meant for non-shower situations. A stand alone as it were. There’s nothing that a vertical surface can be sealed to.
To make things even more interesting, they built a ledge around the whole thing out of 2x6 and tiled it over. So there is about 4-5" tiled surface around the whole tub before you hit a vertical surface (solid sheets of a corian type manufactured surface. Pretty).
As if THAT wasn’t enough, the tile is pretty much below the tub edge throughout, so anytime someone uses the shower, the water pools.
To prevent seepage they placed their trust on grout, plumbers putty and silicone. None of it very well placed as far as I’m concerned.
Having said this, I really don’t want to take the thing apart if I can avoid it. I have enough expenses and work to do without redoing this too. Particularly since I think it was in surprisingly good condition all things considered. I’m hoping that a PROPER silicone seal will prevent water from seeping under at least for long enough to let me finish the rest of the house.
Frankly I’d appreciate any suggestions if anyone has them.
Look, I’m not 100% sure about what you are facing, but if you have other renovations with a higher priority, why don’t you leave the jaccuzi in the basement open so that you can moniter and develop a course action for the future. If you’re leaking water behind it you’ll at least have a chance to mop it up and dry it out.