SunnyDry Concrete and Masonry Foundation Waterproofer Sealer Review
About one year ago we applied Wall Firma’s SunnyDry Foundation Waterproofer to seal more than 500 sq ft. of mostly below-grade cement block in our basement. Our goal in applying SunnyDry’s Sealer was two-fold: (1) to eliminate a small amount of water seeping through the block and pooling near the base of the exterior walls, and (2) to eliminate dampness on the block and reduce overall humidity in the room.
We applied a competitors’ product, Thoro Company’s Super Thoroseal, to a different 500 sq. ft. of below-grade wall space in the basement. This review focuses soley on our experience with SunnyDry. Super Thoroseal is reviewed separately, at that link. In the picture here, Sunny Dry is gray, and Super Thoroseal is white. The wood studs sitting in front of the wall are anchored at the top and bottom of room, and are not anchored to the block walls (this would compromise the waterproof seal).
Selection Reasons and Overall Evaluation
We chose SunnyDry for its economical price, its 10-year guarantee to stop water and dampness in below-grade applications, and its relative ease of application over other types of waterproofing methods (trenching and sealing from the exterior, installing a french drain inside, etc).
Overall, we are extremely pleased with the results. SunnyDry’s Foundation Waterproofer completely sealed the basement walls. We’ve had no water seep through the block; the walls aren’t even damp. Humidity in the room is substantially reduced.
Purchase Information & Price
We purchased SunnyDry Concrete Waterproofer from our local Lowes in 60lb. “contractor size” buckets for $28.98 each (2007 price). The sealer is gray, both in powder form and when it’s dry on the walls. The dull color isn’t particularly important in our application–our walls will eventually be drywalled–it only serves to distinguish the area of the wall covered by SunnyDry’s Waterproofer from the area covered by Super Thoroseal.
Applications for the Waterproofer Beyond Below-Grade Walls
SunnyDry is a a portland cement-based powder waterproofer designed to seal exterior below-grade walls. Wall Firma advertises that their product will work on concrete, brick, stone, or masonry. Our review is limited to concrete block. While not applicable to our application, SunnyDry can also be used in potable water installations (e.g. drinking water tanks), bird baths, fish ponds, fountains, and pools. If we ever build a fountain, they’re top on our list to seal the inside.
How Portland Cement-based Waterproofers Work
SunnyDry’s sealer has chemicals in it that, when activated with water, react and subsequently dry to a water tight seal. The Waterproofer actually seeps into the pores in the concrete block and keep water trapped behind the block. Super Thoroseal claims their product will stand up to 200PSI of water pressure. Wall Firma makes no PSI claim on their Foundation Waterproofer. For comparison, most latex-based waterproofers that you “paint on” seal walls to approximately 20 PSI. I assume that, based on the technology employed in Super Thoroseal and SunnyDry, SunnyDry has a similar waterproofing capability. In our situation, we have french drains built into the exterior front of the house that drain to the rear, so we don’t have a pressure build-up concern.
Foundation Waterproofer Preparation Experience
Overall, preparation was relatively easy, but a bit time consuming. SunnyDry recommends four steps to prepare the walls for applying the waterproofer:
- Clean the surface of the block with a wire brush to remove any loose mortar, paint, or dust on the walls. We didn’t have a wire brush handy, but our walls had never been painted, and were covered with insulation ever since the house was built. There was very little, if any, loose mortar to deal with, so we skipped this step.
- Remove any efflorescence using Sunny Dry Concrete Cleaner or a mild acid. We used a competitor’s product available at Home Depot, which sufficed just fine. Essentially, the acid we purchased is mixed with water and sprayed using a pump sprayer. After application, hose down the walls and vaccuum up the excess water.
- Plug any large holes, cracks, or active water leaks with a quick drying hydraulic cement. Sunny Dry recommends their Hydraulic Leak Stop Cement. We had no large cracks or leaks, so we skipped this step.
- Dampen the walls with regular water using a pump sprayer or garden hose. We highly recommend using a hose, as a pump sprayer simply doesn’t put enough water on the walls. You want the walls to actually be damp during application. It ensures the block doesn’t absorb the water out of the waterproofer too quickly, and as a bonus, it makes SunnyDry easier to spread. You will need to repeat this step throughout application, so run the hose inside.
Foundation Waterproofer Application Experience
Applying the sealer is relatively simple, but very tedious. In a nutshell, applying SunnyDry boils down to a few easy steps:
- Mix the powder with several quarts of water; use a wire-frame style mixing blade to mix. Add powder until the mix reaches a mildy thick pancake batter-like consistency. Note that Wall Firma says you can use a paint mixer. I highly suggest going with a drywall mud mixing blade, as some paint mixers like the ”the squirrel” available at home depot, will clog. Drywall mixing blades are available at the big box, or you can pick up this heavy duty version from Robert’s on Amazon.com.
- Dampen the walls. We used a hose and found this to be a very good method.
- Spread SunnyDry using a Tampico-fiber brush, starting at the top of the wall and working down.
Coating & Coverage Experience
SunnyDry recommends two coats in order to obtain the best waterproofing performance. We found this true. After one coat, we still had some water seeping through the wall. After the second coat, the dampness was eliminated. We actually applied a third coat, something SunnyDry indicates may be necessary at the base of walls or in tough-to-waterproof spots. We did it because we’re paranoid about future leaks.
SunnyDry claims 265-340 sq. ft. of coverage for the first coat on porous surfaces and up to 440 sq. ft. on second coats and non-porous surfaces. We found their claim to be spot-on. It took us approximately five 60lb. buckets to cover our 700 sq. ft. area with three coats.
Final Thoughts
After 12 months of use, many products have left us wanting more – a feeling that we really didn’t get what we paid for. SunnyDry Foundation Waterproofer has left us feeling just the opposite. We’re extremely pleased with the results, and 1 year later, we’re enjoying a dry, relatively low-humidity basement space. Way to go, SunnyDry!
Related Sites
What do you think? Have you had a good experience with a basement waterproofing product?
Comments & Conversation on this Article...
16 Responses to SunnyDry Concrete and Masonry Foundation Waterproofer Sealer Review
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July 3rd, 2008 8:57 am
Hmmm … sounds like a great product. I’m just a bit concerned about the effects — if any — on the color. If it dries gray like that, I’m thinking it would darken all my bricks.
Will be looking to seal my new brick porch and walkway later this summer so your timing on this couldn’t be better!
July 3rd, 2008 9:03 am
Nicole — This product is completely opaque – not a clear sealer that you would apply to brick that will remain visible on an exterior or finish interior room. The difference being that this is a permanent waterproofing solution, where as the brick sealer you would use on a porch and walkway is actually a temporary sealer that will wear off after several years. (SunnyDry is guaranteed to prevent leaks for 10 years).
July 4th, 2008 6:55 pm
Sounds like a great product. I’d argue there’s NO WAY they can maintain 200 psi!! However, using a portland cement based product is definitely the way to go. Portland cement reacts with water and hydrates to create a very strong bond to other portland cement products (block, concrete, etc). The big problem with sealing from the inside is it’s like trying to plug a dam, it’s much more effective to do from the outside. I’m glad it has taken care of your small water problem.
July 5th, 2008 12:21 am
Todd- I wish there were a way we could test this easily to determine whether Super Thoroseal meets its claim of withstanding 200psi (note, just for clarification, that SunnyDry never makes suchs a claim).
And, you’re right about plugging from the inside being a challenge. In most cases, giving this stuff a shot first is the easiest solution. If it proves to hold tight for a good period of time, you get to save all the money/work associated with “fixing it right.”
July 5th, 2008 4:52 pm
My take is it’s impossible. Maybe from the outside and most likely that’s where their claim comes from. The other argument/reasoning they may be using is that most tensile strengths of concrete are about 10% of the compressive strength. So…if you say the stuff has a compressive strength of 2000 psi then maybe you can say it has a tensile strength of 200 psi. At any rate it at least is working for you so that’s great. I tell people that these paints/sealers are a great second line of defense and a great way to keep out small amounts of moisture.
July 8th, 2008 12:42 pm
I’ve got a couple places where something like this could be very helpful. Thanks for the review, Fred. I’m looking forward to the follow up on Thoroseal.
April 25th, 2009 9:13 am
We have a farmstead cheese making facility. SunnyDri was used in 2003 to plaster all the interior walls of a 60×30 block building and a 28,000 gal. block water supply cistern built and Sunny Dri covered in 1998. We have been EXTREEMLY pleased with the results. The interior walls of the facility are washed everyday and of course the cistern is wet and holding a lot of water. BOTH structures meet FDA regulations and have remained bright white[non yellowing], non stained even with chlorine and chemical use. We are now finishing our 2nd farm cheese facility and will guarantee SunnyDri will be on all outside surfaces including the milking parlor. The first facility is in Ohio[now owned by our son] and our second one is in Kentucky and will be named Kentucky Farm Cheese. This building is a remodel of an existing block building that had been painted but last year we put the Sunny Dri over a small painted wall against the weather to test it. It has been washed, frozen, super heated in summer , chlorined and is still super hard and white. The rest of the building is to be done this week. Next is the block foundation of our new home. NOW THERE! That makes us all feel good… sure could use more Sunny Dri
August 26th, 2009 5:45 am
Where’s the Thoroseal review? Been more than another year now. Both still holding up?
August 30th, 2009 7:14 am
I can not find this product on the shelves anymore ?
September 22nd, 2009 9:32 pm
I applied Sunny Dry as per instructions. Everything seemed to go OK.
Now 2 days later the area is “weeping”. I’m guessing that the moisture
I’m seeing bleeding from the treatment is water. Is this normal? How
long before the treated surface will be dry. We’ve had no rain for weeks
hence the “weeping” liquid is not external water coming through the wall.
January 31st, 2010 3:58 pm
Where can I find Sunnydry products ?
January 31st, 2010 9:35 pm
SunnyDry products are available at Lowes.
February 1st, 2010 10:22 pm
Thanks for the review Fred. I’ve been doing some research on how to seal my basement to bring down the humidity and can’t decide which way to go.
I read that the paint on sealers can be pushed off the surface by hydrostatic pressure and start to flake and crack, but they are cheaper.
Did you consider any of the silicate sealers? The premise is that they penetrate deep into the concrete and seal it internally by reacting with lime and alkalis. The silicate mineral seals the gaps permanently. They supposedly bond, strengthen, and waterproof concrete and stop efflorescence.
February 3rd, 2010 7:48 pm
G – We didn’t look into other options such as a silicate sealer. That said, my understanding is that SuperThoroseal and SunnyDry work the same way you describe here…. by bonding with the cement and closing the pours.
Super Thoroseal claims a 200 PSI waterproofing capability… That’s about 10X the typical paint-on sealer’s claim.
May 7th, 2010 12:57 pm
Do you know of a waterproofing product that I can apply to the exterior (below grade) concrete block basement?
I have a finished basement and the cost to tear everything out….
I am going to dig up the outside and attach the leaking problem from there.
Any advice would be greatly appreciated.
Thanks,
Matt
July 22nd, 2010 10:56 am
I’m presently in the process of applying SunnyDry on my basement walls. The walls are hideous looking and SunnyDry has completely transformed the look. Since my house is nearly 100 years old and there was flaking paint (I am using proper procedures to remove as much paint as feasable) I still have some old color bleeding causing some spots to show through. I have already applied 2-3 coats and am wondering if I could paint the walls? This would also soften the very rough texture.
Thanks
Chuck