How To Build a BETTER Crawlspace

Matt visits Wade Paquin to check out the details of this conditioned crawlspace. On this waterfront project, Wade goes over why he chose a crawlspace over a full basement and his trademark slab and mud sill details. 

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[robertrusso]

Note to camera person: when you hear the word detail, shoot it please. 😂

[nriqueog]

Would love to see a video on an existing crawl space being renovated to that level.

[chrism]

Living in a hot, humid coastal area, sealing my crawlspace is the best improvement I made to our house. I didn't do a full encapsulation, but had a company remove all existing vapor barrier and floor insulation. New 10 mil vapor barrier with joints overlapped and sealed, going up the foundation and piers 18"+, also sealed the vents with foam blocks and spray foam, then installed a Santa-Fe dehumidifier. Been installed for 3 years, couldn't be happier with the results.

[lolMyke]

The builder we work for has been foaming under his slabs for years. We are in Canada and do full basements. The houses are raised bungalows and we have alot of bedrock. Helps keep the frost out

[Pembroke]

Matt and Wade, your suggestions are absolutely excellent! A few years ago, I had the privilege of assisting in the construction of something very few people presently hear about;: a "mechanical basement (MB)". Mechanical basements are neither crawl spaces, nor are they entire basements, but they do have simulations. A conventional crawlspace is 4 feet tall, whereas MB is 5 to 6 feet tall, allowing homeowners and tradespeople to easily access systems or store items. A great example is a root cellar, which is just made a lot better – it's made out of concrete instead of dirt or bricks! Hey, some people do use them for storm or fallout shelters.

[SueSosa-snyn]

I live nearbyy and I am soo excited and pleased to see this home being built by Wade...This is Island Park section of Portsmouth RI

[brycestevenson]

Why didn't the camera show the details at the end of the video? Would have been nice to visually see what you were describing.

[RealTechSkills]

Question on this type of crawlspace: If the plywood/OSB decking is flush with the top plate, then how are utilities (plumbing/electrical/etc.) getting up from the crawlspace into an exterior wall?
In traditional framing the floor joists are sitting on top of the sill plate, so there is space accessible to create a path.

I like the fact that a rim joist is eliminated in such a design (if I am mentally picturing this build detail correctly).

[mikemcgown]

Thanks for the information on sealing the mudsills to the foundation walls. Sounds like a great way to work it.

[kelseyboy]

I love this, it’s great. Mechanics Creeper!!! Quick question: Are the floor posts on the floating slab? Or is there peers under those posts?

[benaxley]

I’ve never seen a floor system that is completely inside the crawl space, that’s a interesting way to do it and let your subfloor sit on the sill. It’s interesting to see the difference on building around the country

[sjpropertyservices]

As one who has inspected hundreds of crawl spaces I appreciate how you are building this crawl space. Curious as to whether access to the crawl space will be from inside or outside.

[darrelstickler]

Would love a drawing detailing the base mat and the sill with bill of materials. Hard to follow details across mat and stem walls.

[skycowboyak]

Very nice and clean...thanks. It would also be good if you talked about how to incorporate the water and drain lines into the slab, and what the heating plans were for the crawl space and house.

[bradh]

Sure would have been nice to see some camera footage of those details they are describing. Really low effort from the camera crew in this one

[averagejane]

Excellent information. I have a very problematic crawl space on my small home. Similar environment with a very high water table. None of the previous owners completed a curtain drain at the back of the property so the water comes through the property rather than skirting it. I have no intention of putting in a full basement ever...but would love to go from a disgusting, rodent filled, dirt floor crawlspace that is not well done AT ALL to a sealed and conditioned crawl space that is essentially a short basement. That being said...this has a ton of problems now. So, drainage on the property first I guess then need to assess what all needs to be replaced on the building in terms of structure due to damage. There are definitely sagging floors....I feel pretty overwhelmed...but this video, and videos like these help me to feel less confused and more focused. Thankfully this is s small home to deal with....there is that.

The only thing in this video is that I could not see what you were pointing to with the top of the concrete walls and sealing there. The cameras needed to be angled to see it.

[dmckenrick]

Please consider taking a few minutes and B Roll images of the sealing method. That added visual would be most helpful in explaining the process.

[jackjmaheriii]

A good crawl space is all the challenges of a basement and SoG smoooshed together but this looks like a good one!

[susanwilson]

Beemer a subscriber for 4+ years. Great informational videos and products.
Matt...please work to let your guests speak and finish their sentences without interrupting.

[HondaFarm]

For Educational purposes, can you explain the reason why or what the advantage is of having the concrete foundation crawlspace to begin with? I totally understand the reason behind the 'can't do a basement because of high water table, etc" ... but why wouldn't you just simply do the crushed gravel, closed-cell spray foam and then concrete on slab construction? I'm just trying to justify in my mind why you need a concrete crawlspace at all in this situation. Love everything else and all the fantastic engineering details associated with this build. Thanks Matt!!! Great video!!