Category: foamglas

We are thrilled at the success and completion of our first Foam-Free, (near) Net Zero, Passive House in Western Maryland.  The home is currently in the final stages of testing, certification and interior finishing. Most of the progress can be followed on their website, it’s nicely detailed and as such might offer good inspiration to those DIY types. It has been an educational process with material usage, system selection and install, air sealing and insulation, window install and team collaboration.

The views and placement of the house are extraordinary and achieve the homeowner’s goal of a comfortable, accessible, high performance home designed to view the meadow, marsh and forest.

For more photos of the final walk-thru, visit the project page.

brennan + company’s cutting edge Foam Free foundation detail mentioned in Journal of Light Construction article! Thank you to Michael Hindle of Passive to Positive to crediting us for working together to create this detail.

And suddenly…it’s a house.  The trusses arrived and were set at 24″ on center on top of our 24″ on center 2×6 structural wall on top of our 24″ on center MSR 2×10 floor framing on top of our basement wall.  Walking through the skeleton to see the clean, aligned bones was really exciting.  Our framers did a fabulous job with advanced framing and aligning all the structure.  It sounds simple and straightforward, but I’ve walked in many that seem junked up with unnecessary studs and multiple upon multiple jacks and kings.

The blue line along the top plate is Tescon Vana magic tape sealing the corner edge of our plywood air barrier. Each spliced top plate is taped as well.
Next comes the roof sheathing, finalizing the plywood air barrier and taping all the seams.

The slab pour was a successful event!

LESSONS LEARNED:
1.  Use slumps for leveling rather than puncturing your vapor barrier with pins.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2. Hold your hose up off the vapor barrier.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3. Make sure Michael has plenty of coffee if you’re going to make him get up that early.

 
 
 

Two 5″ staggered seam layers of Roxul RockBoard80 have been laid as our under slab insulation. The total 10″ of insulation was decided on because it simplified foundation construction and ordering. Only 8″ was necessary per dynamic modeling.

LESSON LEARNED:  Next time, we will use the higher 11 lb density Roxul ComfortBoard CIS under slab due to construction traffic issues, and lay boards across for walking paths.  It would be advisable to also immediately cover the mineral wool to protect it from getting wet.

After all mineral wool was in place, our vapor barrier – Tu-Tuff by Sto-Cote – was installed.  Tu-Tuff claims to be an environmentally preferable product and is a cross-laminate, virgin polyolefin (rather than standard polyethelene).

LESSON LEARNED: Tu-Tuff is a 4 mil product, and we tried to tear and puncture it to no avail – it actually was tuff (sorry, Michael) and meets all the technical requirements.  Lesson(s) learned, 1) their proprietary tape is not up to snuff when it comes to sticking for air sealing purposes and we had to scramble to find tape to replace it – always have some Wigluv or Tescon Vana on hand!; 2) you can’t tape when surfaces are wet with dew; 3) Tu-Tuff being only 4 mil and thin did not stay smooth, but rather preferred to stay wrinkled.
 
 

The Roxul Rockboard 80 mineral wool has made its installation appearance on site.  It has even been deemed “fantastic” to work with by our contractor, Jeff Gosnell of Gosnell Builders! We would like to thank the team at Roxul for their endless hours in ensuring the appropriate foundation application of their product.

The lovely turquoise product is our Rub R Wall waterproofing, a 100% rubber, asphalt-free waterproofing membrane.

 

The FoamGlas blocks were placed below the footing, footing poured and concrete blocks for foundation wall are now being laid.

FoamGlas below footings

poured footing over slipsheet over FoamGlas

laying block foundation wall