Skip to main content

Posts

Showing posts from December, 2015

Wall Assembly 2

Outer Wall Assembly A lot has been happening! Since the last post we have... Completed the Breezeway and Garage Foundation Completed the Septic System  Completed the Outer Wall Assembly (We'll refer to it as the Cladding Wall from now on) (View of the Front and South Side) (View of the Back) (View of the North Side) Needless to say we have turned a few heads. The most common question is w here the windows are going or why are they covered up?         Simply put, we are not just going to say we are building a super tight house, we are going to test it before any insulation, drywall, windows, plumbing, or electric is installed to ensure its tightness. And then after those other components are installed we can test again to check those individual components for air tightness. When we are ready to perform the initial blower door I will go into this into a little more detail.  Lets take a look at the Cladding Wall Assembly and Details:       ...

Wall Assembly 1

Double Wall Construction Maybe I am biased to double wall construction because the company I work for Airtight Services  is a cellulose insulation company; but it is still probably the most cost effective way to achieve the R-values necessary for Passive House. Based on our energy model we needed to achieve about an R-54 wall. There were a couple options: 2x6 wall with 6" of polyisocyanurate rigid foam to the outside There are some more difficult window installation details when your window is cantilevered over nothing but foam. Some long screws are need to attached a furring strip over the rigid foam (9" long) and those can add considerable cost to the project - upwards of $0.75 each The labels on rigid foam insulation scared me a little bit too -  15 YEAR LIMITED THERMAL WARRANTY Polyisocyanurate has the WORST embodied energy of the good types of insulation meaning it takes the most amount of energy to make relative to how much it will save This graph was posted on Green Bu...

Floppy Bits

Floppy Bits During my passive house training I learned a rather important "technical" term used pretty frequently during the construction process - Floppy Bit A Floppy Bit is simply a section of material that is used to connect air barriers that are installed at different times. I will be discussing the floppy bit installation connecting the basement wall to the 1st floor wall., but 1st I wanted to review how we came to define the interior surface of the foundation wall as our air barrier. Before we installed the sub slab insulation and the basement slab we installed a radon barrier and sealed it to the foundation wall with glue and tape  See earlier blog post HERE Now the next break in the air barrier is at the rim joist / mud sill.  A Floppy Bit is installed in conjunction with the mud sill to connect the air barrier lines We used Solitex Mento Plus as our floppy bit. This is a very durable vapor open weather resistant barrier. It will allow drying of the building assembly...