Home>Discussions>BATHROOMS>Caulk clarification
8 posts / 0 new
Last post
Smudge
Caulk clarification
Smudge

I am removing old caulk from around the perimeter of a bathtub and partially up the tile walls. If the caulk is in good condition on most of the tile wall, do I need to remove all the way up the wall can I just stop? The old caulk is silicone. And which caulk do you recommend under the circumstance? Thank you.

dj1
Re: Caulk clarification
dj1

Silicone is hard to remove.

Wait until our member SPRUCE reads your post...

HoustonRemodeler
Re: Caulk clarification
HoustonRemodeler

I use only 100% silicone as it never molds (inside the caulk - mold will grow ON anything)

Cut out enough to make space for the new silicone to fit in between and have a good bite and not just lay on top.

Some really nice guy wrote a caulking tutorial you might find helpful

Mastercarpentry
Re: Caulk clarification
Mastercarpentry

Here we go again :p We're pretty evenly split about silicone, but if it's in good condition there's no need to remove any type of caulking. There's a silicone caulk removal liquid available but I've never needed or used it. Once the bulk of the old silicone is gone, a slightly damp terrycloth rag and some vigorous rubbing will remove the residue, then you can re-caulk. With any caulk at tubs or showers two things you must do is ensure there is absolutely no moisture behind the caulking. Water can hide in gaps and behind tiles or sheet goods and whatever you put on top of it will fail or mildew if it's not absolutely dry. Second is soap scum, a TSP wash will cut through that and leave a surface caulking will adhere to. My preference here is silicone. It's not easy to work with but it has more elasticity than any other type of caulking and it never hardens.

I happened to be back at an old job today where 5 years ago the owner had me caulk the tub surround with a "Tub and Tile" non-silicone caulking. I can't say how well that lasted, but in the interim someone came along and blobbed silicone all over and it looked a mess. Water had gotten behind it all and mildewed. Getting the silicone off took maybe 15 minutes but the old caulk had mildewed under it and was hard as a rock. Getting that darkened stuff off took me an hour, carefully chipping at it since nothing else was working. Finally I applied a nice bead of silicone and experience tells me that it will be good for at least 5 years, and when renewal time comes the whole job won't take me 15 minutes.

For a nice bead of silicone, apply it very evenly then mist the bead on both sides with water before tooling with a finger. You can tape off the edges if you wish. You get only one shot at it without re-misting so try to do it all in one smooth motion. If you taped, pull the tape toward the bead at a 90 degree angle as you remove it. For a perfect bead of any caulking, tape both sides with a good painter's tape where you want the bead to stop. Caulk and tool to shape being sure that the bead is even with the tape at the edges, not thicker. Now let the caulking dry completely, 2 days if you can but at least 24 hours. Now the trick- don't pull the tape but use it to guide a razor blade to cut through the caulking, then pull the tape away slowly, cutting again at any spots which need that. When you're done it will look like a factory-made gasket and last as long as the caulking is capable of. If a gap is wider at one end, make the entire bead that width with the tape as that looks better than a tapered bead.

I'm ducking out now before the anti-silicone crew arrives :cool:

Phil

Smudge
Re: Caulk clarification
Smudge

Let me just clarify my caulk clarification question. I am removing all the caulk around the perimeter of the tub. There is also a bead of caulk up the tile walls but I did not want to remove the entire strip as the part toward the high ceiling is not failing and thus very hard to remove. Can I stop half way up the wall, cut a clean line in the old caulk and smooth the new caulk into the old caulk?

Some nice guy said use a tsp wash...what is a tsp wash? I don't need to use that bath and not in any rush, so how long after cleaning all the caulk should I wait to ensure all is dry before applying new caulk?

Thanks for all the hints. Never used silicone caulk and can use all the help.

HoustonRemodeler
Re: Caulk clarification
HoustonRemodeler

Tri Sodium Phosphate

keith3267
Re: Caulk clarification
keith3267

When you say "up the walls", you do mean at the corners where the walls intersect and not between the tiles themselves in the field. The tiles should be grouted in the field. Only the corners get caulked.

If you are not removing all the caulk, then you should use the same caulk as a replacement. If you want to use a sanded bath caulk to match the grout, then you need to remove all the old caulk and replace it all.

Smudge
Re: Caulk clarification
Smudge

Yes, the caulk is only at the corners going up the wall. There is grout between the tiles. I was afraid it was just not done, replacing only the failing caulk and not the entire length. Thank you.

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.