What is a good Flexible Rubber Sealant (Like Flex Seal or Leak Stop?)

[ohland]

I need to close up some unsealed corners on a roof. Yes, I have searched on the correct way, but the ideal of playing on the back of the house (very short run from dormer to edge) is not very comforting. Bond to asphalt shingles, wood, foam insulation.

I don't care if the color match is imperfect, or if there are bubbles or imperfections in the coating, as long as it stops water.

I positively hate playing near the edge. I am a HATER.

[scarry scarney]

I was going to suggest the spray flex seal. Then I read the consumer report. YMMV, but it worked for me.

http://www.consumerreports.org/cro/magazine/2012/06/flex-seal-claim-check/index.htm
The claim. Flex Seal “stops leaks fast and is the easy way to coat, seal and protect almost anything,” the manufacturer says. In a promo video, pitchman Phil Swift applies Flex Seal to a screen door inserted in the bottom of a rowboat, then launches the boat with himself as skipper (left side of the photo above). It floats, of course. A 14-ounce can of the liquid is supposed to treat 2 to 12 square feet.

The check. Imitating the video for Flex Seal, we made our own tiny rowboat with a screen bottom, sealed the screen, and launched the boat in our lab “pond.” We also used Flex Seal on a copper pipe with drilled holes of different sizes, on an unsealed gutter, and on a cracked flowerpot. And we checked claims that the product is flexible and can be painted.



Bottom line. All aboard. Flex Seal floated our boat, and Teddy stayed dry. But with other uses, we hit rough seas. It took three coats of Flex Seal to plug the pipe holes, and larger holes blew out under water pressure. Even three coats didn’t seal vertical sections of our gutter’s end caps and joints: The product dripped down. Flex Seal was flexible but tore when bent too far. And although it sealed the crack in our flowerpot, we had to use two coats of spray paint to conceal our handiwork.

[duckey]

Cool patch has worked for me

[ole 5 hole group]

I used the flex seal sold at Home Depot and it sealed the rivet leaks in a 16' Lund fishing boat. It's held now for 3 years and not a drop.

[CT-shooter777]

stop at the auto-body shop or PeP boys and buy some auto undercoat in a spray can, works great, sticks to everything, including your hands........

[PULSARNC]

Look for a good polyurethane seAlent Granger has them in their catalog

[Alstep]

I have had good success with a leak-seal product made by Rust-Oleum. Got it at Home Depot. Had some cracks in my concrete foundation that always seeped water when it rained. Doug it out and wire brushed the area of the crack, then applied several coatings. Hasn't leaked since.

[Plate plinker]

head out to meandrous and ask for non asphalt roof sealant. They used to sell some stuff that really bonds it might be polyurethane or neoprene. applies white then dries clear. Ive used it even thought it cost double of asphalt, because it performs very well. So well that I tore aluminum before the bond gave out ( yes its that tuff).

[ohland]

head out to meandrous and ask for non asphalt roof sealant.

Like Sashco?
http://www.sashco.com/products/through-the-roof/

Yes it is slightly more expensive than asphalt...

[Plate plinker]

That's not what they had when I was buying that type of thing. Probably good stuff though, like I said just ask them for some non tar based sealant. And not just silicone that won't last long enough.

[SeabeeMan]

I've used flexseal with good success to seal overlapping flat surfaces. I can't speak to its ability to fill holes, though.

[ohland]

That's not what they had when I was buying that type of thing.

Not in stores, pick up at store only.

SealBest Duck Coat White Flexible Roof Coating

Duck Coat is a white, highly elastomeric, rubber roof coating that provides a waterproof sealant over flat roofs. Duck Coat is formulated to hold up to ponding water conditions on flat roofs. Duck Coat can be installed on most roofing substrates including built up roofing (BUR) metal, concrete, EPDM Rubber, TPO, APP, modified bitumen, polyurethane foam, PVC, asphalt, wood and more. Duck Coat can be applied in cooler temperatures as low as 35 ºF.

Highly elastic and withstands roof contractions and expansions
Superior tensile strength forms a tough rubber membrane
Highly reflective finish lowers energy costs
Can be applied in cooler temperatures as low as 35 ºF
Freshly applied coating unaffected by rain or dew and will not wash off
Will not wash off even if rain occurs immediately after application
Helps extend the life of the roof and reduce building energy costs by increasing solar reflectance
Covers approximately 70 square feet per gallon

[ohland]

https://www.amesresearch.com/pdf/HIE_2-20_INV_Roof_Coatings_w_AD.pdf

[Shawlerbrook]

Can’t beat plastic roof cement for the price. Works even on a wet roof and will last as long as the expensive stuff. Most brands are good.
https://www.homedepot.com/p/Roofers-Choice-0-90-Gal-Plastic-Roof-Cement-RC015142/202091024

[Burnt Fingers]

Can’t beat plastic roof cement for the price. Works even on a wet roof and will last as long as the expensive stuff. Most brands are good.
https://www.homedepot.com/p/Roofers-Choice-0-90-Gal-Plastic-Roof-Cement-RC015142/202091024

After five years I think they found what they wanted.

[Winger Ed.]

Clear spray can Flex seal works well for small gaps/cracks.

The roofing 'goo' at the box box or hardware store in a paint can or calk tube is better for wider cracks.
But be careful with getting it on your clothes or skin. That stuff sticks like poop on a baby blanket.