How to Waterproof Concrete Brick | Ask This Old House

Ask This Old House mason Mark McCullough explains and demonstrates the benefits of waterproofing concrete brick.
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Time: 2 hours
Cost: $300
Skill Level: Moderate
Tools List for Waterproofing Concrete Brick:
Paint roller
Shopping List:
Waterproofing agent
Bucket
Steps:
1. Pour the waterproofing agent into the bucket.
2. Dip the paint roller into the waterproofing agent and apply it generously to the brick, bottom to top.
3. The agent will cure in 14 days.
Resources:
Mark applied Siloxane 20 solvent-based water repellant, manufactured by Umaco (www.umaco.com/).
Expert assistance for this segment was provided by MJM Masonry (mjmmasonry.com).
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How to Waterproof Concrete Brick | Ask This Old House
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[@construction-productscemen4935]

Thank you for sharing.

[@btrswt35]

I'm thinking they didn't remember to include what exactly the water proofing agent is.

[@dleivam]

It's in the description, siloxane 20 by umaco

[@groovejet77]

@@dleivam thanks I missed that bit

[@nafnaf0]

Seal-Krete is what you are more likely to find at the Home Depot

[@k.makininayoearle-headley8583]

I wasted mins of my.life trying to find out what the product was??????!!!!

[@gilessmith5057]

Not sure what they used but I’ve used similar and it’s Prosoco Siloxane

[@Bluecollarworker]

What product did you use? What product would you recommend for inside cinderblock waterproofing better than drylock?

[@chizo5097]

Great video

[@shahnazali9269]

I have my basement walls with this concrete brick and it seems to be in the weathered in some places pretty bad where the rain gutters drainage are placed above. Can I still water proof them? Also, this will water proof the side of the wall in basement; but does it also waterproof on the other side facing the soil because it is porous?

[@japan5865]

Beautiful

[@FatesRhysHoward]

these last for approx. 90 days so they are very good! :oo

[@cathiegoodenough3979]

What if you have a brick planter that you want to make into a water fountain? Can you apply that seal and then use epoxy grout on top of it to tile the inside of the planter? I wasn't sure if it would stick.

[@neiltropolis]

What sauce are you guys using. Anti Hydro? Thanks for the upload.

[@iBRiDGE380]

So best to apply during a streak of warm dry days?

[@dawn4109]

CAN YOU USE IT ON CINDER BLOCK? CAN WE USE IT OUTSIDE TO SEAL BASEMENT WALLS TOO?

[@medpub]

The water proofing agent is the most important thing and gets almost zero mention - I believe there are 4 types

[@ijazmohammed588]

It’s in the vid description

[@datmeme8967]

This is like a video titled "How to Bake a Cake" that shows them putting the cake pan in an oven.

[@AK-ru3sg]

Great explanation for school children. Mine are older than about 8 unfortunately but this will really help to educate younger ones. Many thanks.

[@chrisgraham2904]

Google the number of law suits that were launched against Bob Villa and the "This Old House" series when they were on television. "Once a HACK...Always a HACK"

[@abdullatifbinkhamees3069]

So what do you exactly applied? Is there a name for the material?

[@Engineer9736]

Lol they listened to my comment in another video about treating only half the wall to show the difference ;-) Good video. I’m already curious for years if such anti water stuff would help keeping the shower clean. No drying up water on the wall equals no limescale equals no dirtyness.

[@ben-vf]

Richard van Pukkem you might be onto something , It would certainly keep the grout clean .

[@finbarmathews9059]

Great idea

[@chrisgraham2904]

@@ben-vf A quality grout sealer intended for tile will seal the grout to shed the water and grime. All bathroom tile grout should be re-sealed every 3 years...but, nobody does. Many contractors never seal the grout the first time, because it requires them to revisit the site 3 days in a row to seal the grout with 3 coats. ....and that explains all the nasty bathrooms. lol

[@MikeTheMaker1]

Should you start at the top and work your way down? Sorta like shoveling snow if your on a hill. Any drips will drip down and coat the bottom.

[@JeffreyFeyh-rb4xk]

Thompson water seal clear multi surface Waterproofer is one that I know of. They used to have a display at my local Ace hardware with a concrete block that was coated half with the sealer and half without. You could see the difference.

[@King_TuTT]

how long does this water proofer work for till it needs another coat?

[@Sanayas_world]

What kind of waterproofing agent did you use🤔?

[@beholderer]

Can you render or plaster those bricks after waterproofing?

[@zaidkashour]

how to water proof your wall bricks? Use a water proof agent ¡

[@bryant8602]

What products was used for waterproofing brick wall

[@falsealarmno]

I was told that bricks on a house are meant to be porous to allow proper ventilation of the house. & the gutters were supposed to protect the brick from water.

[@HelloWorld-yy6fi]

Rain frequently strikes the sides of houses at a slight angle. As such, the gutters are effectively useless on this angled rain. Gutters are used as a means for directing water away from the bricks and foundation of a structure.

[@chrisgraham2904]

ventilation is provided by the space behind the brick wall and the weeping holes along the bottom row of bricks, not through the bricks.

[@daisywilde5353]

Can I paint over this with drylok?

[@danielgehring7437]

So... Step 1 apply product. Got it. Love TOH but come on.

[@callen7436]

I accidentally spilled some Thompson water seal onto my concrete slab patio area. It's about the size of a sheet of notebook paper. Will it harm it? How do I get it off cause it's a dark spot. The seal was clear

[@grandinfinite5921]

You didn't even mentioned what is the brand name?! What is the name of the liquid you are rolling on the brick? I want to paint my house, but, don't know what product to use. Can you please tell me the name? Thank you.

[@MrJohnweez]

So what if it rains during the 14 days? Do you have to cover it for 14 days?

[@Engineer9736]

jasen ratnam Then what should one do with the 14 days of curing information?

[@Engineer9736]

jasen ratnam What kind of abuse can you do after those 14 days, that you cannot do before it? If you do any brick modifying action, it will be damaged anyway no matter how long you waited. So if it’s safe for rain after one hour, what can you do more to the wall during the 1+ hour to 14 days period?

[@cup_and_cone]

Just think of it like any glue. There is "set time" and "cure time". Set time is before it's safe to let it be, cure time is full strength.

[@killagauil4096]

What type of clay do you use to make the bricks

[@MrPierre8081]

What waterproofer have you used and does it allow the brick to breath?

[@familiardave6540]

All he said was 'a waterproofing agent'.... :/

[@TXEducation]

Would this work on a water fountain?

[@user-in2jw7du9j]

Can you apply this product on top of older concrete block that has been painted?

[@latinreuben]

Is it more water proof than Protectosil Chem-trete BSM 400? I live in NYC area so Umaco product might not be available to me in my area.

[@mac1294]

Hi what would happen if you applied it and it rained a few days later would it ruin it.

[@aslo4812]

How long does this last outside in the weather on a retaining wall?

[@ClassicBMWFanInQuebec]

How long does the protection last before you need to re-apply it?

[@williambiggs2308]

90 days

[@dogfacedponysoldier6040]

William Biggs hahaha.. good one 😂. Actually this type of sealer lasts 10-20 yrs. That's if the brick and mortar joints stay structurally stable. It won't prevent water intrusion if a crack develops in the mortar joint.

[@GDanielCho]

Not very long, I would be surprised if it lasted a season. I tried these spray products which is the same thing in a can and it fade within 2-3 weeks. Exposing it to the elements 24/7? Geezsh I dunno if it will last a season even with such a thick coat.

[@crunch9876]

GDaniel then you are spraying cheap shit. They make epoxy dealers that last 10 years. I’m sure your using indoor sealers. Look up life deck they make good products I think their web cite is lifedeck.biz

[@greatove]

William Biggs t thought 2 weeks lol

[@lucky1206]

The video should be called 'how to waterproof a brick that you will never know what we used'

[@juanquiroz9669]

What is the name of the sealant that was used ?

[@curiosity2314]

How often do you have to apply this? One of the reasons I might buy brick would be that I DO NOT want to paint. I would steer clear of this type of brick, money saved in the long run. We learn lessons from the past and repeat them later?

[@rikpaesschezoone1719]

I want to seal a water thank , wil my water be safe to drink if a use this produkt ???

[@owaisdilkifaryadhalisafdar4870]

Plz can u teach how to make a pool

[@md.abdulgoni153]

What kinds of waterproofing agents you are using?

[@eddyflo2978]

But no suggestions of what type of waterproofing to use was mentioned.? Diy'er would want some suggestions

[@clorindacordova4562]

does this sealer leave a smooth finish?

[@andyamysarizonaadventures5450]

What brand or type sealant!?

[@JosephTammaro]

Cathedral Stone Products, Inc makes a clear coat that doesn't change the color of the brick. R-97

[@thatdamnike]

Did you forget something, Like what was in the bucket?

[@Engineer9736]

That DAMN Ike! It’s in the description, with link to the product

[@Watching4Fun_]

Siloxane 20 solvent-based water repellant, manufactured by Umaco (www.umaco.com/) posted in the description.

[@Airborn14]

Found it here: amzn.to/2ENgZhg

[@anthonycruz9944]

can this seal from the inside out?

[@greggordon2721]

What product did he use?

[@janelbenning8514]

Should Install a waterproofing system

[@migo-migo9503]

Will the brick still be breathable just in case moisture gets in between the brick and the interior wall?

[@stinefibiger7515]

Vere important question.

[@chrisgraham2904]

No...Brick doesn't breath. A properly constructed brick wall has a venting space behind the brick and weep holes for drainage along the bottom row of bricks.

[@GoatzombieBubba]

1:30 ohhh heard in the background

[@ashkrikorian5753]

Is drylok basically the same thing? Im looking to add something to cinderblock to prevent it from absorbing moisture

[@latinreuben]

Looking into that myself. I'm deciding between Umaco here, Drylok - Siloxane 7 Brick & Masonry Penetrating Sealer, at $140/5 gal & Protectosil Chem-trete BSM 400 at $358/5 gal pale. Hard choice for a brick home

[@JeffreyFeyh-rb4xk]

If your talking basement. Drylok will only go so far. Especially if the exterior foundation is not sealed. They do have Henry foundation coating for that. Usually used in conjunction with an exterior French drain around the foundation of the house.

[@chandlerpiggs1006]

Wow that's great, now what's the NAME OF THE PRODUCT?????

[@johnnywadd7960]

Siloxane 20

[@medicalmanport1136]

what about cinder blocks I have a cinder block foundation can that be waterproofed

[@chrisgraham2904]

Not a suitable product for foundations. Find a waterproofing engineered system intended for foundations or hire a professional.

[@afrazkhan3189]

Hello sir, could you give me the name of water proofing agent name please

[@jackjonson2696]

What did you use ??

[@RubbinRobbin]

They didn’t explain what it was made of and what kind of damage it would be susceptible to.

[@dawnmitchell6368]

Can this be used on cinder block retaining wall that appears to be constantly wet?

[@johnnywadd7960]

Try Drylok

[@chrisgraham2904]

The problem is inadequate waterproofing protection on the side of the wall where the soil is piles up. You can dig behind the wall and protect that side, according to building code standards, or just make sure that the next retaining wall you build is built properly.

[@ivanmischyuk9813]

How often should this process be done to keep the water out throughout the lifetime of the wall?

[@xavier2268]

5-7 years

[@michaelzwick6335]

our backyard block fences are not sealed for water. I stuccoed my side and my neighbor didn't. He put planters on his side of the wall and it leaks through to my side. how can I prevent water from penetrating on my side. Help!

[@chrisgraham2904]

You can't. The problem has to be resolved on the neighbor's side of the wall.

[@michaelzwick6335]

@@chrisgraham2904 thank you !

[@JleeA314]

what is the product? what's it called?

[@jjt3146]

What kind of water proofing product did he use?

[@johnnywadd7960]

Siloxane 20

[@RR_DM]

If you like the look of brick but building with brick is not ideal (for example in earthquake prone areas), you can lay a vinyl wallpaper with a brick veneer design😁😌

[@AdvantageVarnson]

I have old concrete brick foundation walls (approx. 130 years). The interior face, visible in the basement, is crumbly in some spots. In the past, someone had painted the walls, little of which remains now. I leave the walls unfinished and exposed now so that they can breathe. It looks bad. I’m trying to find a suitable finish for the interior side. Waterproofing from the inside wouldn’t be wise. Any knowledgeable people have an idea?

[@chrisgraham2904]

The reason the concrete brick on the interior of the foundation is degrading is because the foundation wall is not adequately protected from moisture on the outside of the building.

[@AdvantageVarnson]

Chris Graham - hi. Yes, I’m aware of why the problem is occurring. I live in a semi-detached on a tight lot. On the unattached side, I’m against the property line and my neighbour’s foundation is about 15” from mine. I’d love to replace the old brickwork with a proper wall with weeping and waterproofing but that’s just not in the cards right now. So some breathable paint is a good ‘for now’ sort of thing.

[@robineggblue-bp3rq]

What is the product??

[@jonock1]

Paint it with silicate paint. Lasts a hell of a lot longer

[@youwhobaby]

What is the product called

[@patrickwilson4902]

What's the best water seal for the bricks of my chimney??? SINCERELY You didn't say what you're using 😢

[@iketheranter9126]

Exterior brick ? I like to use Emperor Masonry Creme. Interior ? Drylock if you don't mind white brick.

[@julianarodriguez3635]

How about semi block

[@markfillery1002]

THE product is tompsons water seal here in the uk been around for years, last for 5 years i belive, all it is, is white spirit with some silicone in it

[@chrisgraham2904]

The original Thompson's Water Seal was paraffin wax dissolved in mineral spirits. The new "Advanced" formula may contain silicone. Usually good for 2 years on horizontal surfaces and maybe 3 to 5 on vertical surfaces.

[@oldtwinsna8347]

Why isn't Mauro the one doing the painting?

[@ratchet219]

How often do you re apply?

[@MrMYY]

Looking for answer!!! 🤨

[@chrisgraham2904]

Every two years on all horizontal surfaces and every three to five years on all vertical surfaces.

[@mattg188]

1:53 😂

[@joejr9653]

So I presume this can be applied to a concrete foundation? I'm guessing that you can't paint it after since it shouldn't absorb the paint.

[@ben-vf]

Joe Jr or plaster

[@esadlemes8936]

do u mean foundation as in foundation or basement wall?i don't think applying a coat on foundations is a good idea. a bituminous membrane is a time proven solution for foundations. closed cell insulation like xps is also sufficient waterproofing solution on it's own in less humid areas

[@chrisgraham2904]

Not for poured concrete foundations or for concrete block foundations as it does not provide adequate protection as a long term solution. Use solid or paintable membranes and proven engineered systems that are code approved for foundations.

[@nicholassmith82]

After working in the detailing business for over 15 years, I can tell you that the solution they're using is a genetic makeup of silica dioxide and other similar agents, which is highly water repellent. However, this is only going to be a temporary solution as it would only last for a few years.

[@ncooty]

+Nicholas Smith "genetic"? Do you mean "synthetic"?

[@nicholassmith82]

ncooty No, I used "genetic" in an ambiguous sense.

[@Rollie-go]

you sure you dont mean generic?

[@brettpriester4125]

Ok but what is the product?

[@johnnywadd7960]

Siloxane 20

[@SuperMan-xy8ui]

Silane Siloxane by Umaco - after the bead goes away, the sealer will continue to work in the pores for up to 7-10 years.

[@jballs1118]

What about regular brick from the year 1954??

[@cycloneben5902]

pricy

[@chrisgraham2904]

Regular brick from 1954 is a fired clay brick. That needs no treatments or waterproofing unless your protecting the brick after it's surface has been sand blasted during a restoration process.

[@enanotodo]

looks like tile sealer

[@domenicsandri2740]

You didn’t say what the product is.

[@Idiotsincarshere]

So... what’s the solution?

[@Watching4Fun_]

Siloxane 20 solvent-based water repellant, manufactured by Umaco (www.umaco.com/)

[@2cents996]

That helped zero. What was the agent used? 🤔

[@masterwrong3110]

It’s ceramic coating 9h lol

[@hectormendoza5320]

What is the waterproofing agent Called?

[@caseybarry4327]

Hector Mendoza see the link in the description

[@hectormendoza5320]

Casey Barry thanks, Casey! I may be doing this to my brick work soon.

[@johnnywadd7960]

Siloxane 20

[@GoatzombieBubba]

en.wikipedia.org/wiki/Cream_City_brick

[@Kingsleyrulz]

Dissing Milwaukee I see

[@kevingonzalez3792]

Can’t you just use paint???

[@maker7363]

Ya kinda forgot the MOST IMPORTANT PART.. How to waterproof concrete.( iow what do you use to do it.. showing us how to use a paint brush is worthless

[@genna2337]

why put this up and don't tell what you used?

[@l.e.6263]

Waste of time. No information given. Who builds a house without clay bricks?

[@JoeGP]

cool, but you left every single detail out

[@johnnywadd7960]

Siloxane 20

[@laxmanjoshi5637]

He must tell what kind of waterproof and better show orgenal waterproof bocket because everyone know good think for house.But this shows is useless.Don't make us confusion

[@El16100]

What about Mud Bricks

[@Lyfehurts66]

Why would you post this video without telling us the waterproofing agent you used. Makes no sense. Its like you're hiding it or something when you pulled it from behind the sample smh..

[@chriscolameco6850]

Silaxane I’m provably not spelling that correctly, go to your local Sherwin Williams and ask for the loxon brick sealer (buy the more expensive one)

[@mikejackman4416]

Come on.....is that all you do???

[@germanfreire6301]

Xxf

[@chrisgraham2904]

Another CRAP video from "This Old House". They don't identify the "water proofing agent" they used. Nothing about the product, whether it's water based or petroleum based. Nothing about whether it contains VOC's or how it smells. Nothing about how to clean up tools like brushes, rollers or sprayers. Nothing about protecting other surfaces or protecting plants and shrubs during the coating process. Nothing about the longevity of the product and how often it has to be re-coated. The only information provided is: "ROLL IT ON". The only good information provided here is: "Never build a house with cheap concrete bricks -- Spend an extra 5 cents per brick for a Clay Fired Brick". I just like to watch Bob Villa's boys for a good laugh at how inept they are.

[@Luckingsworth]

They weren't paid to promote the product so they didn't care to mention it lmao