Waterproofing 101: The Science of Keeping Water Out of Buildings

[@TheEngineeringHub]

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[@Johnny-300]

Yes, please more detail videos. I’m a licensed waterproofer in California. Extremely exciting that you did a video about Waterproofing, hope you continue with a series with the different methods and installations. There are only three methods to Waterproof: sheets/liquid/bentonite clay. Thank you again.

[@Johnny-300]

@Simon Simon yeah I hold many certificates through a lot of manufacturers products. I travel different states for all my credentials. Still love for my trade to get some exposure, and this old dog still loves to learns with new methods and new products that my industry creates.

[@Lewis.Alcindor]

Great video, with a nice basic explanation of water management concepts! I have one correction from a building science POV. Air barriers are not vapor barriers, and should not be treated as the same. In modern energy-efficient building design influenced by building science principles, we consider the 4 control layers in the following order of importance: 1. Bulk water control 2. Air control 3. Vapor control 4. Thermal control You mentioned these control layers in your video, but didn't sufficiently differentiate air and vapor control. When controlling moisture, air control is most important after bulk water control because humid air brings in a lot of moisture into a building wall assembly and interior. A small hole in a wall that allows humid air to leak in brings inside significantly more water than vapor diffusion would through a more airtight wall. The last sentence introduces a new concept. An airtight wall is not the same as a vapor impermeable wall. Why? Air molecules are generally larger than water vapor molecules. There are many "airtight" materials available for construction, and each of them have different vapor permeability (the measure of how readily water vapor can pass through). Materials with some vapor permeability allow water vapor to pass through, while vapor-impermeable materials (such as polyethylene sheeting) will block water vapor passage. Therefore, it is most important to control airtightness in a building (after controlling bulk water). However, the placement of the vapor barrier should also be carefully considered because, as you mentioned many times in the video, water will inevitably make its way into the wall assembly and needs a way to dry out via evaporation (water diffusion). Therefore, it is important not to trap this water inside a wall assembly and prevent it from drying out, which can happen if it is trapped between two vapor impermeable layers. Another key concept that you alluded to but didn't explain fully enough is vapor drive. This is the direction that vapor evaporates towards. A short rule of thumb is that vapor is driven from the warmer side of the wall to the colder side. Therefore, the vapor drive will change depending on the local temperature and season (going towards inside in hot summers, going towards outside in cold winters). Finally, I mentioned before that different airtight materials had different vapor permeabilities. However, there are some so-called "smart" air barriers membranes whose permeabilities will change depending on the temperature. In cold temps, they have low permeance to prevent indoor water vapor from going through the wall assembly past the insulation layer, which helps reduce mold-forming conditions inside the wall. In warm temps, they have high permeance to encourage drying towards either the outside or inside.

[@billynomates920]

i wish more people would watch these videos! i spent five years at uni learning all about this stuff and so far twenty years practicing it and yet, for some reason, family and friends who complain to me about their housing can't stand to listen to my lectures! 😅

[@what_to_read]

As an engineer myself, I can truly appreciate the work put into I Love Engineering! The platform is not only refreshingly informative, but also encourages learning and exploration in the field. I especially enjoy how the website provides a range of coding tutorials that really lay down the fundamentals. Being able to enhance my coding skills with I Love Engineering has made me feel more confident in my ventures as a software engineer. Thanks for making this available!

[@lindsay_1849]

wow -- great intro to building envelope concepts!

[@TheEngineeringHub]

Glad you liked it!

[@davidstamenov1084]

Who would have thought there were so many details around waterproofing. Interesting topic, definitely something I didn't know. Keep it up!!

[@TheEngineeringHub]

And we only scratched the surface here too!

[@spidrawebster]

Would definitely be interested in a follow-up. For the first time in my life, I'm living full-time in a travel trailer and it's a mildew nightmare. Most of the homes/apartments I've rented didn't have these problems. So I looked for a video on what the construction industry is doing to keep homes water-proofed. It was enlightening watching your video.

[@boblordylordyhowie]

I live in rural Scotland and surprisingly it is the newer buildings that suffer more from dampness as we are much higher than the river so most have no problem with river ingress. Most of the buildings are from the 1880s onwards and were built in stone, my walls are 2 feet thick but do have underfloor vents which keeps the underfloor dry. The modern sealed buildings suffer more because the building is sealed from draughts which makes dampness a greater problem. They do have underfloor vents but for some that is a hazard when the river breaks its banks. Most people do not understand ventilation, I try to explain it by asking a person to put their hand over their mouth then attempt to breathe. When they can't I tell them that explains, if there is no way in, you can't force it out with a fan. I have a 6" fan and a free flowing 5" inlet so I have through flow and no dampness. There are a multitude of flood prevention methods out there, it just seems like people expect others to solve the problem for them. If you buy a house next to a river you have to expect water.

[@dwaynemurphy8229]

Great video. I'm from New Zealand where we have been through a "leaky building" crisis late 90s to early 2000s so interesting to hear about Vancouver's history. Keep the great videos coming!

[@ifell3]

Great video, was taking a view ideas for moisture inside a van. Happy new year

[@TheEngineeringHub]

Thanks, happy new year!

[@howtomundane3109]

I'm glad this is an important part in my Architectural Curriculum!

[@gosselinkfinecarpentry9786]

You should see my attic after a couple days of -30C 6” of ice on the underside of the roof sheething. I’d never seen it in my 25 years in construction. But I moved from New Jersey to Edmonton so…

[@thudang3039]

Yup, would love to see a more detailed version of water systems. There's always videos that outline some basics of what's being used, often sponsored by companies like Siga/Huber, but not as many as to the why that system is used.

[@johnpaularagon1345]

More please. I'll like all your videos.

[@patrikprekop8975]

Great video. Is it possible to get more details for hot and high-humidity climates? Or any recommendations? Thanks a lot

[@vankupilik5824]

This was well done thank you

[@melvin_0bviously]

Came here to watch a video about waterproofing and now helping the algo because I’m raging on the vapor control comments in the video: Add an air gap behind the stucco or a extra debonding sheet of building paper and lose the plastic vapor barrier and there is no crisis.

[@joannenewlove56]

Excellent Video! keep 'em comin'!

[@geotechswithclemency4442]

Another amazing video. Just learned something they really don't teach us in uni..👌

[@mohammednesredinummer3241]

Definitely more details please

[@jasondrummond9451]

Fascinating! I would love to see more about roof design - and about how repair and possible sloping of a leaky flat roof could be done. I'm also interested in the details of soffits and overhangs, window to wall membrane extensions, and waterproofing/vapour barriers in a stucco coated building. (If you look at the only video on my channel you'll see 'why' i'm so interested in fixing a leaky roof. )

[@boxbiru]

My floor is lower than earth. How to protect waterflow from earth? Thnks for your videos

[@garywhite2050]

Well done 👍🏼👍🏼👍🏼!

[@venderpara7895]

there was or is a expert builder videos regarding proofing thats not coming up on utube anymore anyone seen it

[@Eidi920]

Great video. Would definitely love to learn more about building science stuff. :D

[@patrick555HEX]

BOSS WELL DONE

[@sthenzel]

I´m not a big fan of membranes at all, neither inside nor outside. Our house in part is a timber frame from the 1880s, the outside is only covered by an inch of wood with slate nailed to it. A good decade ago we had to replace the slate (started to get flaky, nailholes got loose), but except for a very small section of maybe 1 sq m / 10 sq ft, the old wood stayed, as it was perfectly sound. The rood is tiled, and those tiles here and there even had light coming through when you looked down from inside, still the attic was super dry (had to retile and insulate the roof due to new regulations, though). The lack of membranes enables walls and roof to dry out, if they get wet in the first place at all. Btw, we´re talking about Western Germany and a city that is considered fairly rainy.

[@ladyeowyn42]

Huh. My 1963 Seattle house has a huge overhang. Now I know why.

[@cameronhoglan]

Great video! I'm a civil engineer, so I don't deal with much things inside the building. It's interesting to see how waterproofing of the building is done. However, after seeing all of this I do wonder if we as a society made a mistake by prioritizing fully wooden buildings. Seems like waterproofing would be much less of a problem if more structures had brick or cmu walls.

[@P_RO_]

I''m a Carpenter and have been involved with restoration work on wood framed buildings over 150 years old across the humid Southern US. There are plenty of even older wood buildings doing well so I think it's safe to say that wood can endure. The thing I've taken away from my studies and experience is that wood needs to 'breathe'. In other words there must be air movement to allow excess wetness to be carried away through the atmosphere. You can seal one side of it (exterior) as long as there's enough 'breathing' with the rest. Old balloon framing, pier foundations, and open fenestration for cooling gave you enough 'breathing' to keep wood from rotting. Now we seal everything up and wonder why it's all rotting away as little as 30 years later. Brick, CMU's, and concrete aren't a viable solution being far more costly, less eco-friendly and renewable, and they also need to breathe or they can retain an unhealthy amount of moisture for human habitation. If there's a real solution it lies in learning to live with nature instead of trying to fight it.

[@ladyeowyn42]

Poor choice in seismic regions like cascadia

[@KathrynsWorldWildfireTracking]

There is a wooden church in Russia that sheds water so fast it never rots. It contains no nails either, only peg construction. So, no rusting, no failures. I believe it is in Suzdal...and it dates to late medieval times.

[@benchippy8039]

The more info the better, expand please

[@jaimeortega4940]

Interesting! Would like to hear more about this topic. Perhaps not using wood in a rain forest?

[@sgaldamesful]

Wonderful

[@ayeshanoormohamed1043]

Nice!

[@RonJohn63]

0:04 Looks like New Orleans.

[@HazmatBoots]

you guys ever watch matt risinger on youtube he is always going over new builds and details.

[@eriks6693]

Neat

[@csehszlovakze]

I'm so glad we don't build most houses out of wood here in Europe!

[@JP-uk9uc]

I couldn't possibly believe it here on the West Coast stupid builders put a fascia board of the roof directly over the top of a window at my neighbor's property. It's the dumbest thing I've ever seen. Never stops leaking into the building. And what's more, the idiots tapered the gutter toward the building. They built the leak into place costing the homeowner thousands over and over and over again.

[@charlesviner1565]

👍

[@jimhanty8149]

Build everything out of plastic stuff … that is melded together with heat guns…and is built on a hull that can float. Put the whole thing under a stainless steel A frame shed…. Anchor the whole thing on 4 points 20 feet down in the ground… if that don’t work your screwed…

[@NigelTolley]

All your stuff will rot due to the water from your breath.

[@jimhanty8149]

@@NigelTolley Ha… NO WAY.. I quit breathing years ago.. ( only 4 breaths a day) breathing causes climate change, so we all will have to stop doing that.. or the green police will come get ,and beat us all. J…

[@SeeTheWholeTruth]

If you are waterproof, and under a hundred or several feet of water.. Im guessing it doesnt matter.

[@HRHKamal]

Not clearly explained at all, just rushing thru the slides 👎