Paintable Silicone at Low temps.

I have some leaks in my porch that need caulking, as it drips inside my basement when this leaking occurs, and also could cause rotting of the underlayment.

I see GE makes a Silicone II paintable 100% silicone caulk, and silicone caulk is supposedly able to be applied down to -20 degrees (it’s currently between 20 and 30 in Michigan right now, where I live), but their website says use at 40 degrees or above. Is this just hedging on their part? The site makes no differentiation between the paintable stuff and the pure unpaintable silicone as far as installation temps, but as I said, I have read that 100% silicone is usable down to -20 degrees, although curing time may be extended.

I have got to seal this up, and this is my best bet. I don’t want to use clear, white, grey, almond, or black unpaintable caulk, as it would clash with the colors on my porch. I am hoping to apply the caulk now and paint it in the spring/summer when it gets wamr enough to paint again. (I don’t care about the clashing when it’s covered in snow).

Any advice would be appreciated.

GE’s websiteis not encouraging:

They do have a support phone number you can try calling: 1-866-275-4372.

Otherwise, is there anything you can do to keep the leaky area dry for the next couple of months?

Yeah, I got that info from the website. Note that it says their ACRYLIC caulks are the oens which must be applied when it’s 40 degrees or higher, and that theri silicone CAN be applied in 40 to 100 degree weather. I will try the support number, because short of closing off my porch (and relocating my mailbox, which is up on the porch) and making the front of the house look like crap (like it did for a few months earlier this year while I completed the reno of the porch), I won’t be able to keep it dry.

An alternative might be to look at marine sealers, in particular the Sikaflex range. These are a moisure curing polyurethane, and used to seal boats. Sikaflex290 is used for wooden decks and can be applied down to +5 C, but with extended cure times. It is paintable. Not cheap however.

A friend of mine sealed his old and leaking hot tub with a few tubes of Sikaflex291.

I think non-paintable silicone caulks have a lower application temp. Paintable ones usually have some narrower working temps.

I’d use the paintable stuff. I’d keep it warm and toasty inside and use it when the sun was on that side of the house that needs the caulk. It might be 35 out, but the area right where you need to caulk could be higher than 35. Even if were close, but not 40, I’d caulk it.

The temp affects working time, ease-of-use, cleanup, spreadability, etc.

I’d probably build a heated hooch using tarps. Is hooch the right word? Anyway, a cheap, temporary enclosure that you could stick a portable heat source in. We always called it a hooch when we were welding in one. A Coleman lantern throws some pretty good heat if you could contain it.

You know, that’s not a bad idea…I have a small space heater that could work for that, since it only needs a few hours to cure, it would probably work out ok. I hate to run a space heater for 4 or 5 hours (it has to get up to temp, too…) but it beats the alternative of a leaky porch.

If it were me, I’d just staple up some blue tarp over the leak, let the snow fall on it, and wait until spring for permanent repairs. Doing a repair in suboptimal conditions just means that you’ll have to redo it again when the first repair fails. As you noted, your neighbors are already resigned to your porch looking like a work in progress.

The problem with that is that I would basically have to cover the whole porch floor in a tarp. In conditions that are already slippery, that doesn’t seem like such a good idea.

Success!!! OSI makes a product called QUAD VOC Window, Siding, and Roof sealant. IT is usable down to 20 degrees F, so this should be perfect for me. and it’s paintable.

For those interested:

To see the 20 degree requirement, you have to download the tech sheet from that page.

The only cautionary note (which you may already know) is that silicone will not adhere to concrete well. So if your porch butts up to any stone or masonry work, I’d pick a different product.

No masonry, so I am all good!