Liquid Rubber L R Waterproof Sealant - Multi-Surface Leak Repair Indoor and Outdoor Coating, Water-Based, Easy to Apply, Original Black, 5 Gallon

If you want a sealant that can handle high water temperature and last the test of time, you found it. I used this to seal my homemade solar water heater tank back in early 2022. Today it still hasn't leaked although the tank has reached 130 degrees in summer. Four years of abuse and still reliable is a solid proof of its quality.

I did give it a 5 despite one issue- The positive first - Had a leaky flat roof (slightly racked) over my garage - Was going to have it done professionally for over $5000 ish. To replace the existing membrane. Well Liquid Rubber has a help line email so I asked them if this product would work well - and gave them details of my roof etc. - I got an immediate response and then ordered 10 gallons, based on the surface area etc. This was my bad - but to do I believe the recommended 5 coats it took about 6 gallons - since this stuff is bit pricey I could have ordered 5 gallons and 1 gallon and saved $. Good news is the roof did not leak anymore, and looked good. Here was the complaint- I had left a black rubber garden hose on top of the garage months after applying the sealant- maybe it was up there in the middle of August for 3 weeks- Well when I went to remove the hose it was stuck to the roof - It was not that hard to pry it away but it actually left kind of a stain on the roof. So my bad for leaving the hose there but I did not expect that. I have to check but I will have to do this again at some point-

Absolutely blown away by this product. I was used to those roof sealers made out of tar that never really dried, but just dried out. This product dries to a phenomenal rubber shield and it sticks to anything it comes in contact with. A slight word of caution. It took me several hours to clean out my spray gun after unsuccessfully trying to spray it with my airless sprayer. There seems to be no mention of any product that will act as a solvent for removal. Baby oil, patience and elbow grease is what it needed. After the spray gun fail, I purchased and threw out afterwards, some cheap dollar store brooms for application on my courigated metal roof. Recommend at least 3 coats for a lasting, worry free, seal.

This liquid rubber is definitely easier and less messy to work with than the Black Knight asphalt roof coating. Finishing looks great, ie. because of its viscosity, it's easier to apply and when dry looks like a good seal. I have applied 3 layers. Leaking seems to have subsided but still not 100% on the area where there's a puddle of water. Will apply another layer when weather is dry. Even though the problem is not entirely solved, based on what I see, I am still hopeful it will work after another layer.

Applied 4 coats to my osb timber shed roof within a 2 day period of no rain about a month ago.. We've had some heavy rain since and also some really hot days and so far so good.. have enough left for one more coat. My roof is 3m x 5m.. goes on brown then turns black quickly... Time will tell..