remove latex caulk

Old 12-03-02, 03:39 PM
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remove latex caulk

How can I remove latex caulk from tub?
Old 12-04-02, 05:23 PM
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Replacing caulk

The Winning Strategy: Remove the old caulk, clean the surface meticulously and THEN apply the new caulk.

The best way to keep your caulk in tip top shape is to apply it properly in the first place. So, the first step in replacing caulk is getting all the old caulk off. Though you can do a patch job that will last for a brief period of time, a complete job gives the long lasting results.

Pre-clean the work area...

This is a vital step to a successful job. By pre-cleaning the area with a good combination bathroom surface cleaner / soap scum remover before removing the caulk, you will introduce less moisture around the tiles than you would if you cleaned afterwards. After the old caulk is off, the final cleaning will be done with alcohol... more on this later.

Remove the old caulk...

Try to determine the kind of caulk... it will help you to plan the removal! Get a sharp knife and try to cut it. If it is very rubbery and somewhat soft, it is most likely a pure silicone caulk. If it seems to be very hard, then it is probably one of the latex caulks, such as Polyseamseal, Phenoseal, or one of the hardware store brands.

If you have a silicone caulk, it can be removed with a sharp, single-edged razor in a razor blade holder. Be very careful to keep the razor angled low so that you don't scratch the tub or shower pan, especially if it is a plastic or fiberglass. A utility knife can also be used to cut the caulk from between the tiles and the tub if the razor can't quite get it out, especially in deeper pockets and corners! Sometimes, if you have a porcelain tub, little black lines will appear on the porcelain as you scrape off the caulk, even though you know you didn't scratch the surface. These marks usually come off with the alcohol wipe. If they don't, use a little scouring powder or Soft Scrub... with a minimum of water.

If you are struggling with a latex caulk, a heat gun can be a helpful tool. The heated air will soften the caulk to ease removal. Set at a low temperature (under 300, or your guns lowest setting), to protect the surfaces and your hands. Keep the heat gun moving to prevent overheating of any area... you want to heat and soften the caulk, not cremate it! Work your way around the enclosure, softening the caulk first and then using your tool to remove it. This strategy is unnecessary for silicone caulks because they are softer and easier to remove.

Once the caulk is scraped off, the area should be thoroughly cleaned. Wipe the joint down with denatured alcohol and allow it to dry for a few minutes. The alcohol does a good job of cleaning off any remaining soap scum, grease, or other nasties and yucks that may have crept under loose caulk or you may have missed during precleaning. Use a vacuum to suck out any bits of pieces of caulk that may be lurking under the edge of the tile.

Unfortunately, the alcohol will not kill mildew. If the area was heavily mildewed, you may want to spray it with a concentrated mildew killer after the alcohol wipe. The alcohol cuts the soap scum better than most anything, and gives the mildew killer a fighting chance to knock out any residual mildew. Let it sit for a few minutes, then wipe off any residue with a sponge, rinsing frequently in hot, clear water (no soap). Then, you can use your heat gun to blow dry the area to be caulked if you are in a hurry, or just wait overnight and proceed tomorrow!

It is always a judgment call whether or not to wait overnight before recaulking the enclosure. If you are replacing the caulk because of leakage, or if it was obviously falling off, you would be wise to put a small fan or heater in the enclosure and let it dry out at least overnight.

If you are replacing the caulk for cosmetic reasons... the main one being mildew... you may be able to recaulk immediately, as long as you are using a latex caulk, and in your judgment there was no leaking into the wall. Latex caulks will still adhere if surface is slightly moist. If you are using silicone, then there is no debate... the enclosure must be dry as a bone or the caulk will fail!.

If you have a recurring mildew problem... reappearance in a few months or less... let the enclosure dry more thoroughly next time you caulk, as long as a week in some cases.

Time to choose the new caulk...

If you are working with a completely ceramic enclosure, you can use either the silicone or latex caulks. If you have a fiberglass tub with ceramic tile walls, or a completely fiberglass sectional enclosure with caulked joints, you may be better off using a 100% silicone product.

There is a product from a company called Phenoseal that is advertised as mildew proof. Skeptic that I am, I tried the product in my own home before inflicting it on customers. The stuff deserves high praise. It does indeed stay mildew-free longer than any product I have ever used, and under the most adverse conditions... my kids' bathroom!! I have used it successfully in all types of enclosures, though you will have to use a heat gun to remove it in a fiberglass enclosure, as mentioned earlier.

Because it is relatively soft, pure silicone caulk is the choice of manufacturers of fiberglass enclosures. It is easy to work with and has good smoothing qualities. However, the silicone leaves a slimy residue on your hands that will not wash off with anything I've tried every solvent, soap, and hand cleaner, and none work! Even the GE Silicon web site is silent on this!! The only cure for the silicone greasies is that tried and true cure of many of life's torments... time.

I am not a real fan of the so-called siliconized caulks. These are latex caulks with a small amount of silicone processed into them. I just don't see any advantage to them, advertising notwithstanding. Since silicone is a product designed so things don't stick to it, how can mixing silicone and latex improve the product, other than give the manufacturer a new advertising angle? So, I do not routinely use these chameleon-like products.

Applying the new caulk...

This is the part of the project that separates the mice from the rats. It's a sad truth that, no matter what pains you go through to prep the enclosure, carefully pick the proper caulk, terminate the mildew... all anyone is going to notice is your artistic application of the caulk!!

Having a caulk job look professional is a tall order, mostly because there are few professionals at caulking. In new tile installations, joints that should be caulked are grouted, only because it is a pain to leave the horizontal and vertical seams grout-free for caulking.

Caulking is more of an art than a craft, a mixture of finesse and experience. And every job turns out a little different... some better than others. Even the type and texture of the tile can affect the quality of the job. And using white caulk with colored grout is about as frustrating as you can get!

However, don't loose heart! I can give you a few guidelines that may help you do the best possible job:.

If you don't plan on making caulking a profession, you don't need to use a caulking gun to do your enclosure. The small, plastic tubes of caulk are usually adequate to do an entire enclosure vertical and horizontal seams, along the shower doors, and along the outside floor and walls, if necessary! Though I have become quite skilled with the guns, the fact is that the tube is more easily controlled by the novice and pro alike!! I use the gun myself because I use so much caulk that the large capacity gun cartridges are more economical!

Don't cut too large an opening in the end of the tube... the larger the opening, the more likely you are to overcaulk the joint. The trick to neat caulking lies in not applying too much caulk to the joint. When you smooth the joint, any excess caulk tends to slop all over the place. It's not the end of the world, just makes getting a neat job all the more difficult. You can always add a little more caulk in any spots that need a touch more.
Forget about the ice cubes and special "smoothing" devices that look like gynecological instruments! Raise up your hands and look at them... you are seeing ten custom made tools for smoothing caulk! The technique I use is simple:

For latex caulk, have a small bucket with a damp sponge nearby. The sponge is to wipe off your fingers as they accumulate caulk, and also to keep your finger "tools" moistened so they slide on the caulk without sticking to it.

For pure silicone caulk, have a roll of paper towels handy as well as a damp sponge. With the silicone, the towels are to wipe off any caulk that may get on your hands (remember, the silicone is not water-washable), and the sponge is to moisten your clean fingers for smoothing, as with the latex caulk.

Do both vertical seams in a tiled enclosure first, then the back wall, then both sides. The outside of the enclosure is done last. On a sectional fiberglass enclosure, the pattern is the same.
Apply a bead, no more than inch wide right into one of the joints. Remember... not too thick... you are going to have to get the feel of this. Use a finger, moisten it with the damp sponge, and glide it along the joint, pressing the caulk evenly into the joint . If you have applied the right amount of caulk, the gap between the end of your finger and the joint will smooth the caulk to a neat, even appearance.

If you overapplied the caulk, this is where things get messy! You will have to try to remove the overage by using your finger and the sponge to wipe it off. If you really overdid it, you may want to completely wipe the caulk out of the joint and try again, rather than fudge the job! Needless to say, the latex will clean up better than the silicone... another good reason to not overapply the caulk.

As you finish a section, if there are any spots that seem to have too little caulk, add a little and smooth it in with a finger. Work quickly, because you only have a couple of minutes before the caulk begins to "skin" over!!

Plan on doing the whole job at once. Take the phone off the hook, and put the dog outside. If you stop mid-job, the start-stop seam may not adhere well... a entry point for water and mildew growth!

Let the caulk dry at least overnight and, for God's sake, take a shower!!

CAULK ALL THE TIME... PEOPLE THINK YOU CRAZY!! The Natural HandyMan. Retrieved 04 December 2002.

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