Under-Slab Prep | Getting a PERFECTLY FLAT GRAVEL BASE for your CONCRETE SLAB FOUNDATION

[@napolitanotile2919]

I love the enlightening video,Would mount a 2ft level on top of the screed 2x4 so you can reference for the guy on the other side of the line,,,just a thought

[@LuminairPrime]

Great vid, and thanks for pointing out that gravel no larger than pea gravel around exterior plumbing is code!

[@michaelmolter6180]

We used birdseye sand. Its a lot like 1/4" pea gravel with no fines so it flow really nice. Easy to work with.

[@chewdoobautomotivedetailtm2883]

Wow man I can listen to you for hours. Ty for the info

[@alexalexx8095]

Great video. We are doing similar thing but doing foundation and slab in one pouring

[@btheonekh]

You’re doing quality work, bravo 👏

[@hayleydwyer6768]

Man, these videos are so helpful!! Thank you for putting them out!!

[@pargolf3158]

For smaller jobs, and amateurs like myself, instead of using the string for screeding where you have to constantly check the distance between the screed board and the string, wouldn't it be easier to use long metal pipes that are parallel and level with each other, then just slide the screed board on top of the pipes?

[@HeirloomBuilders]

Absolutely. That’s basically how we level the gravel footing for precast concrete wall systems!

[@pargolf3158]

@@HeirloomBuilders Thanks for your response. Enjoyed your vid.

[@bac4998]

That’s an impressive base.

[@geronimoanonimo4282]

Excellent explanations! Keep em comin bro

[@michaelpetroci-lo1nc]

It’s much faster to set 1/2 -1” pipes in perpendicular with your screed direction. Use an Aluminum screed board that is much longer such as 12’ and up .Much faster with more consistent results

[@HeirloomBuilders]

I love that idea.

[@youjustgottadrum]

Just find finish grade, use laser grader on loader, then put in your 4" of dust. It will be perfectly level, and then harden a bit to walk on but easy to dig for plumbing. Then trench for footings. Way faster, more accurate, and way cheaper.

[@Acolis]

do i need to put the gravel stone down or can i pour directly on the dirt? its a small slab like 8x10

[@valleyscharping]

You don't absolutely need gravel, but it helps a lot. Creates longevity and helps with moisture coming to affect the slab. If you won't be using it for a lot of weight, might not need it.

[@tuanas458]

how do you remove the subbase and prep that for the base?

[@RandyLott]

Im trying to level my gravel driveway for a pad pour. It's impossible to screed because it's packed tight. Any ideas? I have to use my full strength to sink my shovel into it. Thinking the only option is a skid loader.

[@HeirloomBuilders]

@@RandyLott or a box blade on a tractor might do it. If you wait until it’s wet, it’ll shape a lot easier

[@faridability7611]

Does the gravel need to be above ground level? Also, would the bordering edge beam / wall foundation trap water in? Any help would be appreciated

[@HeirloomBuilders]

@@faridability7611 yes, the top of gravel should be about 6-8” minimum above the surrounding grade. The penetration for under slab plumbing will allow water to escape. Just make sure to caulk that penetration once you have a roof cover

[@faridability7611]

@@HeirloomBuilders Thank you so much for the info

[@joshuajackson8112]

Thanks for the info I’m doing a back patio was wondering if I rent a compacter should I compact the gravel after it’s poured or the dirt too before I lay down the gravel as well. Was thinking just to compact the gravel after its spread great video thanks for the info!

[@HeirloomBuilders]

You need either virgin soil that can pass a load bearing capacity test or a packed pad of dirt (I.e. pack the dirt before you lay gravel.)

[@sparksmcgee6641]

Then you have to get the gravel compacted to the listed condition in the engineering. Honestly that plate compactor they used won't get it in a single pass. You have to do it in lifts of a couple inches with those. Each compactor has a rating depth.

[@Level_No_Curve]

How thick and deep is your foundstion wall? I'm thinking about doing a 6 inch slab with no wall and doing a thinker base and good drainage

[@HeirloomBuilders]

@@Level_No_Curve this one was built on a 24” wide x 10” thick footing, the foundation wall is 8” wide and 12” high.

[@nhislove1]

what are the specs of the perimeter walls, as for how deep and how wide? thanks

[@HeirloomBuilders]

These walls were 8” wide x 24” high, but the height will depend on your surrounding grade and frost depth

[@nhislove1]

@@HeirloomBuilders thanks. I'm in Kentucky, and am told you don't have to have the outer walls first, just the slab on grade. What's your thoughts on that?

[@HeirloomBuilders]

@@nhislove1 slab in grade is fine. We separate the wall from the floor since we heat the concrete floor (to prevent heat from transferring through to the outside)

[@nhislove1]

@@HeirloomBuilders gotcha. that sounds good. won't be heating my slab.

[@chrissvenningson1747]

So are you actually laying styrofoam sheets across the whole slab prior to pouring ? Rebar / mesh over foam then pour ? Thank you !

[@HeirloomBuilders]

That’s right!

[@chrismagnum2710]

Yall are working from the neck down. With a 6'-8' horizontal 2x4 laid flat with a 3'-4' handle made from a 2x4 you can do the same thing from a standing position,not be breathing all that silica and use a Lazer level. Get it close with a yard rake and then get within a 1/8" with the 2x4 push-screed contraption while someone else comes behind with a Lazer level

[@anagramconfirmed1717]

Limestone rarely has silica in it. MSHA categorizes limestone dust as "nuisance dust." It has an allowable limit. I agree with you 100%, just wanted to clarify.

[@muddirt8040]

Why didn't they put pipe in before all the gavel. And dig hole and the work again.

[@HeirloomBuilders]

The pipe has to be bedded in pea gravel or dirt. And it’s much easier to dig sloping trenches for drain pipes in gravel than packed dirt.

[@wisdomspitter7688]

Uggh, this is exactly what I needed to know except I’m using 57 gravel, it’s a bear to work with

[@HeirloomBuilders]

I made that mistake once too. I’m sure it’ll be the last time for you to use 57s as well.

[@tylerstone2917]

Love the clean build site and the clean work. Was wondering if you could tell me how you determine how much gravel you need for compacted fills? In my head needing 95% compaction means I should multiple my total volume by .95 but am wanting to know if I need a buffer to account for compaction of the material?

[@HeirloomBuilders]

Compaction only makes the gravel settle about 1/2”. We usually order the volume that we need to go 1” higher than the desired level( and then compact it to the level we want it. There will be some extra gravel, but that is used on the French drain and other places gravel is needed later.

[@tylerstone2917]

@@HeirloomBuilders Awesome thank you so much for the response!!

[@Brandon-no3vc]

what size compactor is that? why not put foam 1st then the vapour barior?

[@HeirloomBuilders]

I think the plate compactor is 18”. You can get it at Northern Tool. We put foam on top of the vapor barrier so we can staple our hydronic radiant heat tubing to the foam.

[@Brandon-no3vc]

@@HeirloomBuilders yyou dont get concrete under or between foam?

[@HeirloomBuilders]

@@Brandon-no3vc we tape all the seams so we don’t get concrete in between or under the foam.

[@Brandon-no3vc]

@@HeirloomBuilders vapour barriors still suposed 2 go ontop of foam board

[@HeirloomBuilders]

@@Brandon-no3vc says who?

[@cowsgohuh7328]

#78 means it’s 7/8 washed rock?

[@HeirloomBuilders]

#78 means pea gravel.

[@WoodchuckNorris.8o]

I love it

[@dominickmasonry3878]

Why foam?

[@HeirloomBuilders]

@@dominickmasonry3878 foam is the only insulation that has the compressive strength to support the concrete above it

[@dominickmasonry3878]

@ I’ve seen it fail, no reason for it.

[@HeirloomBuilders]

@ in what circumstances did foam fail under slab? We make sure the gravel is screeded flat so there is even support for the foam.

[@anthonyjimenez40]

ima start my own business doing this

[@gregpellegrin8713]

Hand screeding compacted stone/sub base layer with wood ? I don’t think that’s doing much of anything lol…..

[@HeirloomBuilders]

Watch and see my friend

[@anthonysheard7408]

What is the gravel base? Limestone?

[@HeirloomBuilders]

#78 stone, granite in my area

[@ghettoliscious]

If Apple were to do concrete slab prep.

[@anagramconfirmed1717]

Everybody laughs at me when I screed the gravel base until I'm coming around the year after to tear their work out.

[@gregpellegrin8713]

Because it’s not doing a damn thing, your better off hitting with compactor again and taking it out again….

[@anagramconfirmed1717]

@@gregpellegrin8713 a) you're b) level, consistent sub-grade/substrate is vital to the pad/pour c) i'll stick to using my compactor AFTER the grading is done and proper, id rather no screw my clients and customers.

[@TJCarpentryServices]

@@gregpellegrin8713 stupidest thing I’ve ever read in my life. I feel sorry for whoever you do work for.

[@LOFHOBL]

How many guys does it take to start a gas powered leveling plate? scratches head did it require a second guy wasting time and pay standing there watching the other start it? Hmmmm probably not but hey its 1 way to milk the cow right? I mean.... clock.

[@HeirloomBuilders]

Ha! The things you catch on camera. We hadn’t started that thing in over a year. I think it ended up being bad gas.

[@gregpellegrin8713]

3 guys on that size slab isn’t exactly milking it lol

[@WilliamFiler]

Take your sunglasses off when you are on camera. People like to see peoples eyes.