Super-Insulated Termite-Proof Slab-On-Grade Foundation

[@jpabmx]

I like your videos, first time I've seen this, I want to see the finished product for sure! 👍

[@rtheprizeisright7323]

Are the 24" footers, is what's called for in weight bearing capacity, or does GA even have a frost line, b/c you all have such a beautiful state(except for I-95 thru Atlanta, that's insane, I had a really bad incident traveling to FL thru there, I'm sure I'm not the only 1, lol) with warm weather. and can you explain the turn ups and turn downs. I'm sorry, I love Roxul videos and advance insulation and building techniques, as I think, in our country, we have the opportunity, to build great solid, weather proof buildings. I wish we would switch, to more concrete, like they do in other countries, as our buildings would last much longer, and if properly build, wouldn't have bug, breaking/cracking, and molding issues if built correctly. But great informative video.

[@squeekhobby4571]

Great work man

[@LGSquared]

Thanks, @Squeek Hobby!

[@jezza6575]

How did you detail penetrations for termite mitigation? I’m sure you did as the rest of the details are spot on.

[@LGSquared]

Here is a video short of howe we dealt with all penetrations in the slab. kzbin.info4gj7NCRF3CE

[@NewVisionLCS]

That is going to be one efficient house!

[@krb365]

Is the flashing aluminum? What gauge?

[@LGSquared]

Yes, that is 24 -gauge pre-finished aluminum that was fabricated in a local metal shop.

[@krb365]

@@LGSquared Thank you. Looks amazing!

[@ABZD019]

Do termites tend to get into below grade insulation here in the south? I know Joe Lstiburek says never ever put the vapor barrier under the insulation because it can never dry, but with Rockwool I think it's open enough it could. So could you put the Rockwool over the Pango and under the slab to keep termites from eating it? Would they even try to eat Rockwool?

[@pingpong9656]

Does that type of rockwool not wick water? I would not want a porus material going into the ground like that....?

[@jonathansage2147]

It will wick water. It insulates the same whether it's wet or dry. Rockwool specs it for this use case (Owen's Corning does not do the same for ThermaFiber caveat emptor). Wet insulation won't hurt concrete. The Z flashing detail he has is actually super critical for this exact reason. It will prevent water from wicking up into the rockwool covering the sheathing. He only mentions it's there for termite protection, but it's way more important for water. I wonder if he will have problems with water challenging the foundation to sheathing seam though because the flashing will be taped above it. I ran a C flashing capping my sub-grade Rockwool in addition to the Z flashing he has here. Time will tell if it matters.

[@pingpong9656]

@@jonathansage2147 That does not sound right - rigid foam has air trapped in it - the air is the actual insulator.... if wool is wet, it has no air, and will not insulate....

[@jonathansage2147]

@pingpong9656 you're right. I looked up Rockwool's moisture guide. It doesn't wick water, it's hydrophobic. So it performs the same when wet because water gets pushed out of the material towards the cold exterior and sits on the exterior until it dries. The only time Rockwool will become soaked through is during a flood and that would damage it's ability to insulate while soaked.

[@wilcoxcl01]

Termites only need a finger nail width to enter. This is a great effort, but it's not termite "proof" just a minor deterrent from them.

[@nicolasarias6000]

Are those comfortbatt or comfortboard

[@jonathansage2147]

Comfortboard for sure

[@MADKingR]

Why not use ICF?

[@enzo1406]

ICF is made of XPS foam right? My best guess is that they are trying to their best to reduce carbon footprint. XPS has more than five times the embodied carbon by weight than dense-pack cellulose. See: www.greenbuildingadvisor.com/article/faq-why-some-builders-avoid-foam-insulation

[@Jimbo4575]

Nope. Sorry to tell you this will be a termite nightmare in a few years. This is from someone with 28 years of experience in the termite industry. While termites don’t eat the rockwool they will tunnel through it to get to wood.

[@LGSquared]

No need to be sorry, @Jimbo4575. We're not concerned about that, still. We're definitely aware of that possibility, but not concerned. The liquid-applied air and vapor control membrane (PolyWall BlueBarrier), while not confirmed (via lab testing) to be a termite barrier, does prevent termite intrusion to the wood sheathing and framing, because it is on the outside of all of both. The manufacturer has done their own testing and confirmed it is termite-proof. The membrane continues from the framing/slab intersection, to every inch around the entire enclosure. We know that the membrane is uninterrupted, with virtually NO hole or gap, because we tested it (with blower door) multiple times, and each time the result was at or below 0.05 ACH50. That's 0.05, not 0.5. The point is that there is virtually no opportunity for the termites, once they get through the 4" of stone wool, to penetrate the membrane.

[@jonathansage2147]

​@LGSquared that is a phenomenal ACH50 congratulations.