Nudura Insulated Concrete Forms (ICFs) & Siga Majvest Air/Weather Barrier - Full Video

[@neckofthewoods24]

what air do you need to block with a solid concrete wall? its good the foam is protected but air was already stopped by the foam and concrete.

[@onemojoman]

Precisely! Canadian code recognizes cast in place concrete as both an air and vapor barrier. The BC Housing "Building Envelope Guide for Houses - Part 9" calls the ICF a "complete assembly" for air and water resistance.

[@Jdlhomesvancouver]

You are correct, concrete can be used as an air barrier and it is recognized as an air barrier but it doesn't mean it doesn't have it's challenges. Especially when we are moving towards Step Code 5 and an air exchange of 1 or better.

[@runmarkrunheinrich]

It is still a good practice to apply a membrane outside with an ICF foundation system.

[@jameschupp2230]

Excellent! Good Job! Good detail, well spoken, straight to the point!

[@Jdlhomesvancouver]

Thank you for your commment!

[@rafflesmaos]

Might I ask out of curiosity why you did a fairly expensive vapor barrier on above grade ICF? Most articles that I've read generally say that it's not needed at all, as the foam + concrete itself acts as a vapor barrier.

[@Jdlhomesvancouver]

Good question! On this particular project, using the concrete as the air barrier was not practical. Using an exterior air barrier was required!

[@Real_Tech_Skills]

@@Jdlhomesvancouver : Would you please elaborate more on your answer? How is it that an ICF wall filled with concrete needs an air barrier? I see no way for the air to travel freely through the structure as long as you have no voids in your concrete of ICF interlocking forms. Why was the Siga air barrier required?

[@matt-justice]

Don’t wanna speak for them, but if you’re using siding that allows moisture runoff behind, saturating the concrete isn’t the best idea.

[@Real_Tech_Skills]

@@matt-justice a moisture barrier and air barrier can be two different things, so I'm not sure why your comment showed up on my reply. If a drain plain is used behind sifing, then I don't see the need for an air barrier. Just trying to see if there is a technicial need for an air barrier with an above grade ICF wall assembly. I can't see how there could be any air movement between the interior and exterior envelopes of the wall assembly.

[@rafflesmaos]

I've been reading up probably way more than I should on this, and based on one article I think there is a case to be made for a moisture barrier. In theory if water can make its way under the siding and into the foam, it can go all the way down the wall following the cracks in ICF into the below grade foam and concrete, bypassing the waterproofing membrane there. I've yet to actually read any reports or recommendations on this from ICF manufacturers though, which seems odd to me. It's likely that this mode of failure would take decades to detect and show up especially if the siding is good. Best thing I could come up with in such a scenario is to either use the waterproofing membrane from roof to footers, or to use some (any reasonable) cheaper waterproofing barrier above grade, and overlap it on top of where the below grade membrane starts. That way any water will always stay on the correct side of the membrane(s). But yeah, that aside, on the vapor barrier part I've yet to find anyone requiring them for ICF walls...

[@andrewallason4530]

I would love to see an ICF block especially made for use in footings. Two L shape foam pieces arranged to form the top and outer sides, with a top gap where the wall blocks lock into. Using a longer version of the black cross-ties and reo-mesh frame already installed. Just set it on the ground, pack sand around the bottom edges, and build your block wall up from there for a monolithic pour. If the design called for it, set the blocks on heavy duty plastic moisture barrier, which can then be turned up the sides of the footing and wall, and tucked into the top prior to the pour. No holes in the moisture barrier, just a few dabs of adhesive to hold it in place.

[@FJB2020]

Check out 'The Foothold' ICF footing system.

[@paulnovak833]

Liteform makes that product

[@Jdlhomesvancouver]

Great idea!

[@joeschlotthauer840]

Why are tubes under the footer at 1:53...

[@Jdlhomesvancouver]

Great question, we will use PVC pipe to create a chase for our electrical and water services to the mechanical room.

[@carloszavarce1715]

Does the peel and stick not act as a super efficient air barrier?

[@Jdlhomesvancouver]

The peel and stick is designed to go on the ICF on a subgrade surface and it transfers to another product that is designed to be above grade but it's not recognized as an adequate air and weather barrier and it is significantly more expensive.

[@JackMeoff_234]

Curious why you use unassembled panels and insert webs? I’m a Nudura user in Florida. Appreciate your feedback.

[@Jdlhomesvancouver]

@@JackMeoff_234 No special reason, they were just out of stock of regular blocks at the time of our order. Thanks for the inquiry!

[@thelittlebluecar2938]

Good job and well explained. Nice project.

[@Jdlhomesvancouver]

Glad you liked it!

[@jefferykeeper9034]

Seems to be and no one can answer this question about icf's what would it be involved to do an addition years later?

[@Jdlhomesvancouver]

Hi Jeff, You would have to use a specialized concrete cutting company to come in and cut additional openings to allow for further additions to the home. With the right equipment and sign off from engineering additional openings can be cut into an ICF foundation simply.

[@cornpop7805]

I've heard a building science professor being interviewed on Matt Reisinger's channel, The Build Show say something to the effect of "It's impossible to insure that no moisture gets in, the more important question is how will that moisture escape once it does get in?". Have you made provisions for the water to escape once in?

[@Jdlhomesvancouver]

Excellent question, in this particular case any moisture that would enter the wall assembly not unlike the moisture in the concrete during construction it will wick outward through the exterior weather barrier but also it has the option to wick inward and be removed from the house by the HRV system as this assembly does not require any interior vapour barrier.

[@stephenlacher5460]

Hitting the foam with a hammer!?

[@Jdlhomesvancouver]

Hi Stephen, the Nudura ICF product has a plastic web running through the block from top to bottom which our staff is tapping with a hammer to secure the interlocking clips in place which stop uplift during the concrete pour.

[@fromtheburbstothetetons8826]

@@Jdlhomesvancouver Which is really nice, but what if he misses the plastic web? My trainer told me his favorite "tool" is a short 2 x 4. 😉

[@MegaBobtube]

yeah, I noticed that

[@LouiA1]

Bad idea - the webbing is plastic as well

[@scottlurken9667]

Air barrier treatment over the ICF, 🤔? Really, 3,000psi poured concrete between two foam forms will have air leaking? 🤔 and sticky plastic will solve the issue 🤔? Sounds like a waste of time and money 💰

[@Jdlhomesvancouver]

Hi Scott, due to the complexity of using concrete as a primary air barrier, it is our preference to use a WRB as the primary air barrier.

[@paulnovak833]

You should have had icf headers. This is one of the main advantages of icf and you dropped the ball

[@Jdlhomesvancouver]

Thanks Paul! 🤪