Caulk and adhesive are two unsung heroes of many building projects. Mostly unseen they soldier on to make our creations stronger, more weather resistant, and better looking. Throughout the late 90’s and early 2000’s I used Bostik Chem Calk on a number of jobs. I was impressed enough to make the statement “If you want caulk that will survive a nuclear holocaust, use Chem Calk”. While that statement was probably over the top, I’ve got 20 year old beads that have maintained their integrity, and still look good.
The main problem with Bostik products, is finding a supplier. While they are available online, I haven’t seen them in any local retail locations. A search for distributors, turned up 3 possible locations within a 100 mile radius of my North Georgia home. Remembering my fondness for Chem Calk, led to contacting the PR department for Bostik. They came thru by generously providing us with four of their products. If you are still awake, read on to see how they worked.
Bostik Home Heavy Duty Construction Adhesive
As the name indicates, this is heavy duty adhesive. It has good body, flows well, and quits running when pressure is released from the gun. I used it primarily to build wood surrounds for 4 vinyl replacement windows. Drying time was good, and the slight overruns from the joints exhibited good bonding. To get a better idea of how well the bond would hold, I glued a 4″ lap joint between 2 pieces of 1×4 treated. After curing, the 24″ long “bridge” was laid across 2 concrete blocks, and carried my 150 lbs. with no problem. Not real scientific, but I’m confident the glue works like it’s supposed to.
Bostik 2000 Advanced Urethane Sealant
Touted as the ultimate in hybrid technology, the 2000 is available in 4 colors and designed as an exterior sealant suitable for most siding. I used it on vinyl and vinyl coated aluminum, and it worked well. Moving to the inside, to caulk the gaps around the windows, the results were not as good. The first attempt was with a tube that had been used on another project. The tip was cut square and too large. I had a 1/4″ gap to fill, and thought it would probably work. In short, the caulk went everywhere, except where it was supposed to.The 2000 has a creamy consistency, making it harder to force into a crack, and smoothing the bead with a finger, forces it out and around instead of in. Hell bent on redemption, for me and the caulk, I cut another tube and tried again. The results were better but not what I wanted. The gap around the window was too deep, and with nothing to flow against, a good bead just wasn’t meant to be. In hindsight I should have used a filler around the window, and the results would have been way better. Paint with latex.
Bostik 915 Polyurethane Sealant (Professional Grade)
Available in 9 colors the 915 is another heavy duty, all around sealant. Suitable for most applications; including roofing, siding and concrete, I didn’t find much it couldn’t do. Used sparingly on inside trim and around windows it worked pretty well. Bostik recommends against using on cracks less than 1/4″ or to fill nail holes, but I did both, and the results were fine. The polyurethane base is sticky, making it hard to get off unfinished wood, and the heavy consistency makes for some hard gunning. Being heavy and sticky made it ideal for “gluing” turnbacks on window aprons. Outside I used the 915 on metal roofing, around vinyl windows and as an impromptu crack filler on a block foundation. According to Bostik, the 915 can accommodate joint movement up to 50%, great for the settling, expanding and contracting all houses go thru. This a good, go to caulk, that I wouldn’t hesitate to use in most any situation, and its paintable.
Bostik Chem-Calk 1200 Commercial Grade Silicone Sealant
Silicone is the traditional sealer in high moisture control situations. I had several projects, ideal for it’s use, and was anxious to try it out. Light bodied and free flowing, the 1200 was easy to gun, and good beads were achieved. I used it to seal a few stray nail holes in a metal roof, as well as the open end gaps under the ridge roll. In a more technical role, vinyl siding around a large electrical panel and meter base called for a little strategy. Some custom flashing and a tube of 1200 later and it was ready for the perfect storm. Like all silicones it skims quickly, so best results were had by running one section at a time and then smoothing. Do overs don’t work well. Also, like Most silicone, you can’t paint it. Available in white, black, and clear.
For info on the many products Bostik offers go here http://www.bostik.com.sg/Products/Construction/Adhesive/ChemCalk_Sealant.
Keep it tight—————Ron