Sikaflex
Finally, good all-around caulk. Sikaflex-1a is a premium-grade, high-performance, moisture-cured, one-component, polyurethane-based, non-sag elastomeric sealant. It is simply the best there is for the money. I've used it for the past 10 years to seal windows, doors, siding and cracks in masonry. It is what silicone should be. It stays completely flexible and is paintable and easy to work with. It comes in many colors and is relatively cheap -- $4 to $8 a tube in good hardware and paint stores. The only disadvantage it has is that it can't be sanded.
Other caulk is either difficult to work with, sags or degrades over time. Silicone is especially frustrating. I've had to dig it out after a few years of exposure to the weather as it loses its adhesion and no longer provides waterproof protection. Goodbye silicone, hello Sikaflex.
Available from DHC Supplies
Manufactured by Sika Construction
Favorite (15)
james
Interesting that you say finally . . . and then follow that with I've used it for 10 years. I will keep it in mind though, thanks for the pros and cons.
Z
I used it for the first time a couple of weeks ago to glue Kerdi waterproofing membrane to the tub lip. It was recommended as a good replacement for the Kerdi-Fix proprietary sealant that runs $25/tube if you can even find it.
It is definitely something you'll want to put to tape down around if you want a clean joint, it doesn't tool anywhere as easily as say, Big Stretch, but few caulks do. And you'll need xylene to clean up any mistakes. But it is super tenacious once set and extremely flexible. No where near as messy or hard to gun as silicone (but maybe that's just me. I never liked working with silicone). Once I get some more time under my belt with it, it'll definitely be one of my goto sealants along with Big Stretch.
Another good thing about it? It's available at my local HomeyD. I recommend looking for it over by the concrete, where it seems all Sika products get stocked. Since it has a shelf-life (I think they recommend <1 year), look to see if it's got a manufacture date on it.
Some other highly recommended urethane caulks are Sonolastic NP1 and Vulkem. Depending on where you are, they might be easier to find. Some of them are available as a two part caulk which is probably best avoided for the inexperienced.
Davey
Sounds promising. I've tried every caulk I could find around the shower/tub, but still get mildew/mold within months. Any reason to think this one would be different in terms of mildew resistance?
Nick
@Davey: Sounds like your problem isn't the caulk, but the environment. Is it possible to improve the ventilation to exhaust the humid air after bathing? Installing a more powerful ventilation fan, or confirming that your ventilation exhausts properly (no kinks or extremely long runs in the ducting) would probably help. Do you find that you have moisture beading on surfaces after showering?
If you haven't already, try the after-shower sprays that contain a surfactant. This will help keep the shower area cleaner and give the mildew and mold less food. Clean the tub/shower area really thoroughly with a bleach based cleaner, then use the shower spray after every shower. It just takes 10-15 seconds to mist the shower thoroughly.
Wes
I will have to keep an eye out for it, and give it a try. My current favorite is Lexel, expecially for flashing around chimneys, siding joints, and roof vents, but Lexel is pricer than Sikaflex.
Fritz Gorbach
Never tried sikaflex products because I can't seem to find them around here, and I certainly can't be bothered mail ordering caulk, but I've had some great luck with the Sherwin Williams brand polyurethane caulks, and who knows, maybe sika makes them.
As for silicone, I regularly use two GE products. One is Sil-pruf, which I use quite often outdoors, in applications such as sealing new flashing over old, sealing electrical disconnects and meter boxes to buildings, ,(even works well with brick and concrete block, and sealing around penetrations for electrical conduit, gas pipe, or galvanized and plastic pipe. I use this at locations I have regularly visited, for several years and have seen no breakdown.
The other is a construction silicone, I think it is SCS 2000, but I'd have to go look at a tube to be sure, I could have it mixed up. It used to be a plain purple tube, and now it's a little more flashy and green. It only comes in clear, as far as I know, but I have been to jobs where this was used as a sealer, or even an adhesive, and 15 years later it is still intact.
The downsides, though, are that it is not cheap -8 or 9 bucks a tube, wholesale, probably only sold in cases, and you will have to find a professional builders supplier to buy it from, cause they don''t carry it at the big box stores, or any hardware stores I know of. None of theGE products available at depot, or lowes, even come close.
That said, I have found the (fairly)new GE paintable silicone, to be handy in certain applications, but it does sag, run, and drip worse than just about anything else.
Webb
Also the only product to use in your pool. This product was recommended to me by a pool intaller. I was having trouble with my in-ground pool joints. I applied it over 10 years ago and haven't had a problem since. It is impervious to chlorine.
Fritz Gorbach
Sorry. The proper numbers for the sealants I mentioned are -
Ge 2000 - Sil-Pruf, and GE 1200, construction silicone. Checked the tubes at work yesterday.
Paul
You don't want to use polyurethane caulking indoors. It's too gummy. Standard contractor practice is: polyurethane outdoors, silicone indoors.