20 Best Chimney Waterproofing Products (2022 Updated)

I saved myself approximately $400-$500 on a chimney crown repair using this product. The instructions are easy to understand and follow. The product can be applied with a 4″ paint brush. The danger is working on a ladder or a roof.

I have a ranch home, so I felt relatively safe. There are YouTube videos showing this product being used. A normal crown repair would involve removing the broken concrete from the chimney/roof and getting rid of it.

Then mixing concrete on the ground and transporting it to the roof. Then pouring the concrete into the wooden form created around the chimney to hold the concrete as it dries. This product being sold creates a pliable, yet hard seal over any cracks or pieces of broken concrete located in the chimney crown.

No need for new concrete or building forms around the top of the chimney. My repair has withstood large summer rainfalls. A Michigan winter is approaching, yet I feel confident.

My chimney was sealed seven years ago by a professional at a cost many times what I paid for ChimneyRX alone. Directions were easy and straight forward. That I followed to the “T”. The old product was blistered and cracked that had to be removed.

I spent far more time in preparation making sure that I reached the bare mortar. After wetting the surface with water from a spray bottle. I applied a light first using a 3″ paint brush. Then started the same process on the second chimney.

After I put the first coat on the second chimney i added a heavy second coat to the first one. Waited an hour and applied the finish coat to second chimney. A long afternoon well spent. Looks good and after a weeks wet weather I could see that I solved the leaking issue.

I will inspect the chimneys regularly, and hopefully will last for a few years.

This is a preliminary review. It has not yet been tested meaning rain or hit with a hose. The product applied exactly as expected. It is definitely thick! I threw the brush away afterwards. I followed the instructions and the coating is even and it also tightly seals all the surfaces it touches.

Of course you need to work it in, then smooth it out. It leaves what I’ll describe as a rubberized texture on the chimney crown. My initial impression is this is a solid product.

Product went on just as advertised. Did both my own and my parents cap. Went up and checked a week later to confirm good adhesion, no cracking etc. Chimney cap looks new again. Just don’t let your chimney get too bad and you’ll save yourself money in the long run.

It is very easy to use. Clean the surface with a wired brush then apply it with a three inch brush. If you have a much deeper area to apply what I did was fill it up with mortar cement then finish it up with crown repair.

this repellent is the best. The multi surface aspect is wonderfull. This stuff works on anything ! I proofed a cab for an atv and now staying dry as hot sand on miami beach. One 12oz. can will do quite a large area.

The aerosol can is very convenient to avoid messy cleanups.

This product worked great on sealing my glass block wall. I cleaned the glass blocks with regular window cleaner. I applied two coats on a non-windy day, allowing drying time between them. The next rain.

not a drop of water leaked into the house!.

Why is this so expensive compared to Ace? Don’t pay this price.

I got this stuff in hopes that I could repair my favorite raincoat after the arm had been torn. It worked like a charm. I was worried that since I was going to be patching a sleeve that it might seep through the tear and attach to the other side of the sleeve.

I put some wax paper on the external tear site and I sprayed some patch onto the inside of the sleeve. I gave it the evening to dry. My two concerns were: 1) How tacky it would be if my skin were to come in contact with it 2) would it be able to hold the frayed edges together so that it wouldn’t be noticeable on the outside.

I felt no real difference from the raincoat that wasn’t patch and the area that was patched. First concern was not an issue. I have to really look to see where I patched it on the sleeve. Everything is holding well and it is waterproofed.

The tear was only about 2″ long so it was not huge but it was definitely large enough to give me a soaked arm when it rained. Since I have patched the sleeve I have no leaky arm.

The patch and seal spray comes out extremely thin and runny. It is difficult to get it to spray where you want it because of how thin and runny it is. You have to use several coats to get it thick enough to not run all over.

It sprays out nicely with an even stream ,similar to spray paint. It does dry very well. It doesn’t leave any sign of a cover up, you can’t see where it is after it dries. It does keep a watertight seal , no leaking appears around or underneath the area.

Just not happy with how thin and runny it sprays out.

I really enjoy using this product for outdoor sealing of cracks. Gorilla Glue brand is always trusted so I wasn’t surprised to find that this product worked as advertised. Application is very simple and it can be stored away without using all at once.

Glad there is more on the shelves than the flex seal so I definitely recommend this to others.

I got this tape to fix the siding on my mobile home skirting. Over the years the weather takes a toll on our skirting and siding. I used this clear tape to patch up some holes in the skirting. I recommend reading the label before ripping it off and not being able to.

I used sharp scissors after measuring what size I needed and they worked really well. I would suggest a sharp pair to cut through the thickness. The backing came off easy and went on and sealed up nicely.

I didn’t find any faults with this brand of tape! I prefer it for heavier projects. I have not seen any leaking and noticed a difference in the air flow for the better!.

We love to go camping and always had duct tape with us in case we needed to mend something on the fly. While that seemed to work OK, this Gorilla Waterproof patch & seal tape works SO much better. Hole in your tent? Hole in your shoe? Backpack strap break? It will work for any of these things and get you through until you can get a real replacement (or, sometimes it will work so well you won’t even need to get a replacement).

This is perfect for camping, hiking, boating, wherever you might not have access to other tools and supplies.

Tried out this Waterproof Patch and seal clear tape. This tape is extra sticky, durable, and really sticks where you place it. When I was cutting a piece of the tape, it would stick to the scissors. It stuck in place very well.

I placed it on the bottom of my screen door to prevent cold air from coming in and it worked great. I felt no air coming in. Overall a really great tape that works extremely well.

Had a new driveway installed last Fall aprox $7000. Wanted to seal the concrete & brother referred me to the Thompson brand. 3 days later, the beautiful driveway is now blotching! What a disappointment! I hope the sun will bleach out the blotchiness.

Will never use the product again!.

This is not a good sealer. It might be easy to put on, which other reviewers mentioned in their writing, but it isn’t durable. It lasts a couple of years, max, here in the Midwest. Look for a spar varnish, a marine varnish, or a UV protectant polyurethane.

This isn’t the answer you’re looking for. If you want to compare it to other things, look at the ingredients.

Added a nice finish to our deck, easy to work with and only needed one coat. Very pleased with Thomson’s, a name you can trust!

I am trying to fix my glass window water leak during heavy rain. My glass window has 4 X 5 square panels (within the bigger windows) with aluminium strips separating each panel. In between the glass and the aluminium there is a rubber sealing which I think is the cause of the leak.

I could not figure out which panel is leaking. Hence thinking of sealing every panel. Each panel has rubber sealing running along with the glass and the aluminium. Hence the sealing needs to be done between glass and the rubber.

My windows is exposed to sun after midday. Do anyone know whether this spray might fix the water leak issue?.

I was looking to seal my 12-foot aluminum boat on the seams and rivets where I had slow leaks. I sprayed this sealant on pretty abundantly, and I attempted to use masking tape about 1. 5 inches from the seam thinking I could tear it off after it dried to give the seal a more presentable look.

I let it dry overnight, but when I went to pull the tape off the next day, the sealant kept stretching and coming completely off in several areas (didn’t hold too well too the aluminum). Also, inside the boat, water soon started seeping under the coating as I started to use the boat.

I’d sprayed the sealant during the warm summer, so the drying process overnight was during warm temperature. Maybe this sealant might work better for lighter jobs on non-smooth surfaces, but it is not meant for the job I attempted on semi-smooth aluminum surface.

And don’t expect a neat appearance. While spraying, splatter tends to jump at least half a foot away from the intended target. I used a sheet of cardboard to block most of the splatter, but I realized that quite a bit of the spray ended up on the cardboard.

Curious if the “as seen on TV” Flex Seal actually performs better?.

I have tried different brands of silicone over the years and most are pretty much the same, with the biggest variation being price. Caulking is a good thing given the caulk holds up and works. I find 100% silicone is very effective in sealing and being waterproof.

Lasts. Dries clear like it should. Fills the cracks like caulking is supposed to. A bit goopy, but that’s normal The clean up is a bit more than other acrylic caulking, you need mineral spirits. So wear gloves.

he only things you have to worry about when using it as a project adhesive: 1. If you’re using it to attach things for projects, it can come apart if it takes a sharp blow or falls. I don’t recommend it for areas which will be bearing a lot of weight or tension.

2. If you use it attach natural stones to something, be aware that very porous stones like limestone or sandstone may react adversely and dissolve over a few weeks. Silicone is more than caulk. It’s also a great adhesive.

I used this product to adhere mylar-backed bubble insulation to my garage doors. It sets up quickly and holds most materials. Most importantly, it doesn’t get hard, brittle or shrink, so it will last a very very long time.

I used this to seal up where the backsplash was separating from the wall. I hope to keep out water from dripping behind there and bugs from going behind there. I cut the tip to the smallest size because I didn’t want to create a goopy mess.

Dispensing the product was super easy. It might take a little strength to squeeze it out thought especially if you are using the smallest opening. But once you get it going and get the hang of it, it’s easy to use.

I squeezed out a line and was happy that it’s not super noticeable. The pics are before and after applying, but I went a step further and smoothed out the line (not pictured) to make things look a little neater.

That was easy too as long as you do it immediately before the sealant starts to cure.

I have found so many great uses for this sealant! I love that it’s clear. We have done a door frame repair, a window leak repair, and sealed up some old weather stripping with this stuff. It hasn’t failed us and does a great job even when it gets wet.

The sealant still holds. I will say that you need to be careful with the tube. Instead of squeezing it out, start by rolling the bottom a little at a time to get the sealant out. It will save you some frustration of wasting product.

But honestly, it is such a versatile sealant that you will find so many uses for. You’ll want to always have a tube of this around the house for repairs. I give it 5 stars without hesitation.

I used this about a month ago to ‘seal’ the corners of a 304SS reservoir holding water where the seam/weld had separated a bit. I had first tried JB weld (the metal one), and it didn’t quite do the trick.

This stuff painted right over that, and the sealed the corners. One thick coat probably would have been good… but I came back 2 days later and did a second coat… then waited about 4 days to fill the reservoir.

1 month in and no issues. I think it worked. Hope this helps because basically couldn’t find anything on U Toob or internet where somebody did this same thing to coat the inside (only the seams) of a reservoir to make it water tight.

It’s about 10ft x 2 x 1 ft deep.

I have had a leaking roof near the seam between the roof and porch, and no matter what I’ve put on, it continues to leak. We actually need a new roof, but we can’t do that expense right now. I decided to try the Flex Seal on the portion that I thought was leaking.

I easily applied this with a brush and roller, but it is a thicker consistency than paint, so be aware of that difference. It seemed to dry pretty quickly, because when I checked on it a few hours later it was pretty firm.

It is like rubber so it really forms to the surface that you paint it on. I had a little left, so I also coated an old hammer handle and it seems to be adhered to it pretty good. We did get a small shower and it held up, but waiting until we get a heavy rain to see if indeed it holds at least for a year or so until we can afford a roof.

So far, I am impressed, and if it does hold up well, I am thinking about using it to paint my basement to make it moisture proof and then I can turn it into a game room at some point and not worry about mildew or mold smells.

When I went to buy brushes and a roller for this, the salesman at a large home improvement store had said that he used the product for everything and he highly recommended it. I can see lots of uses for this product, since it is flexible and easy to apply.

I’m usually wary of those “as seen on tv’ products, but I think this could be a winner. Pros: applies easily, flexible, not strong smelling, Cons: have to use mineral spirits to clean up, can dry quickly if you let the can open while working with it.

Seems lioke it gid a good job. good coverage. 3 gallons did my stone chimney 4’x4’x26′. Concentrated on mortar joint and 2nd coat hit the stones.

applied product to chimney – went on easily – hoping to care for condensation on inside of chimney in house – prompt service – items packaged well – 3rd time ordering from northline – will do so again

Applies easily with sprayer. Water beads on the surface when applied properly. Follow application directions. Northline Express a reliable company to deal with.

I used this Extreme latex-based waterproofer on my interior basement walls to complete the last half of basement. I love the way it coats–thick, so follow recommended coverage. If you have a rough surface, you will need to press hard to work it into the concrete.

I wanted the job perfect, so I applied the 2 coats and then searched for those pin holes to paint over them (you will have them, too, so find them and paint over them!). In year 2000, I did first half of basement with the oil-based waterproofer (no longer avail).

The Extreme is an improved product (mildew-resistant!! and better warranty and latex-based). You can feel the ceramic particles (but wear gloves). Clean up is difficult: hard to wash it off of hands, gloves, brush–consider a roller a one-time use; everything will dry crisp even if you TRY to wash it.

Before applying the Extreme, I used the DRYLOK Etch (don’t skip this product). Then I used the Sikaflex with a caulking gun to fill cracks and holes (small to medium; up to 1 inch or little larger–long story).

Sikaflex is also a great product, elastic and waterproof. It is easy to paint over (wait 72 hours before painting it). You will look at your finished walls and get that satisfied feeling: they look great, will perform well, and will keep your basement dry.

Get the Extreme product and don’t skimp to save a few bucks on a lesser product (not even the regular DRYLOK latex-based). The Extreme is the best.

package arrived early and was very secure in the box. Excellent service. Thanks.

Great product a lot easier to apply than the original which I have applied in the past and has a smoother texture, the key is in the preparation and the two-coat film thickness but the results speak for themselves.

Could not be happier with the results.

The Product worked as stated. Putting on with a brush is almost impossible for a very large area. I applied half the product with the suggested brush and the other half with a commercial knock down sprayer.

The knock down sprayer with the correct nozzle works best.

Wonderful product for my 800 gallon above-ground fish pond. I applied Thoroseal about 10 years ago and it’s just now showing some minor cracks. The orange metal bucket is the old packaging. The new container is a sturdy white plastic bucket.

Note that the old product formula has not changed, only the bucket.

Picks up tire marks very bad. Ruined a nice double coated driveway with full dirty tire tracks. I had used this same product several times over the years with no problems and great results, but they must have changed something, even though I waited 3 days to drive on it, it picked up every track.

Terrible. Hate it!.

this works really well for a damp basement floor but gets dirty sooooo easily. i did the moisture test with a plastic bag and there was nothing after 2 days. you will need to go over it with floor paint if using for a floor.

I did a garage floor paint and it seems to be holding up well. just don’t expect to paint this on and be done. even on the wall section we painted it yellowed very quickly. you will need to paint over it again so maybe another product might have been better for me but the moisture barrier is really wht I got it for and that works so I am happy.

Acrylic is a good water proofing p product. Have used for many years.

I bought a sample bottle and did a test on a single paver. Products like this take 3-6 months to properly evaluate since they are affected by sun and time but after only 3 days I am not impressed. The percent solids dissolved in the liquid seems to be much lower than competitive products that I have used and I would NOT buy that product to seal my pool pavers.

Been using this product for a number of years. Really effective and when the low sheen goes away, we take that as the sign to add another coat. Literally took minutes to apply with roller to porch and stairs.