There is a significant change coming to the National Building Code of Canada (NBC).  Specifically Section 9.36 of the 2015 edition of the NBC, known as the “Energy Efficiency” section of the Building Code or simply the “Energy Code” .  This will change the requirements when building a new home to include specified levels of efficiency needed to satisfy the Code.  Prior to this section’s adoption, the only requirement was that a home must be able to maintain a constant temperature in winter (eg, 22⁰C in living spaces, 18⁰C in unfinished basements, 15⁰C in heated crawl spaces).  In other words, a hard working furnace can make up for minimal insulation (and all for the cost of….well, a high heating cost….).

Enter the Energy Code for homes, which has been implemented in other provinces for several years, but will officially be adopted in Saskatchewan on January 1, 2019.  What does this mean for the average builder/homeowner?  Simply put, it will ensure that new homes will be built with a level of insulation that ensures occupant comfort and reduced heating costs. 

There are 3 paths to compliance under Section 9.36:

COMPLIANCE METHOD

This is the most straight-forward approach to meeting the requirement of the Energy Code.  The National Building Code clearly lists minimum requirements for insulation levels (FYI - the amount of insulation is often measured in RSI or R-value where the higher number equals more insulation), as well as HVAC (heating, ventilation & air conditioning) and water heating requirements.  We will focus briefly on the insulation requirements (since this is our focus & area of expertise at Prairie ICF).  The table below lists the requirements of 9.36 for various building assemblies (you can also download a copy of this table for future reference HERE).

9.36 Compliance-page.jpg

A few important notes:

·      Different RSI/R-values are listed for different components of building envelope (eg, foundation walls vs. above grade walls vs. basement floors, etc.).

·      Higher levels of insulation sometimes required for a home without a Heat Recovery Ventilator (HRV) installed.  Given the inherent air-tightness provided by an ICF wall it is recommended to install an HRV/ERV to ensure adequate ventilation.

·      R-values listed refer to WHOLE WALL R-VALUES(!).  This is possibly the biggest shift in thinking when compared to previous applications of the Code.  For instance, when you insulate a 2x6 wall with fiberglass batt insulation it is commonly referred to as an R20 wall, since the insulation purchased would be listed as R20 on the bag (although once it is compressed into a 5.5” stud space its effective insulation drops to R19).  However, each stud is a weak spot (AKA “thermal bridge”) in the insulation (wood insulates at approx. R1.2 per inch thickness).  Therefore, a typical 2x6 (“R20”) wall with studs at 16” o/c (meaning wood is about 23% of the exterior wall assembly) has a whole wall R-value of only R13.4!

·      Since NUDURA forms have continuous insulation on both sides of the concrete core, there is NO thermal bridging.  This makes for an easy calculation.  The complete wall R-value of NUDURA’s forms is R-23.59 (RSI 4.158).  This exceeds the requirements for below grade and above grade walls with or without HRV in our local climate zone (Zone 7A).

·      Prairie ICF has various options to meet the listed requirements for insulation below a basement slab (NUDURA Floor Technology, HYDROFOAM) and ceiling assemblies (NUDURA Ceiling Technology) to complete a well-insulated building envelope.

TRADE-OFF METHOD

There are cases where prescriptive whole-wall insulation levels cannot be met.  For instance, a framed tall-wall that necessitates a close stud-spacing that increases thermal bridging to a point that minimal insulation levels are impossible.  In this case, Code allows for reduced insulation in this area of the wall to be offset by increased insulation (above code minimum) in another area, essentially allowing the two areas to average the required insulation levels.

A second (simpler) option would be to build with NUDURA, which can easily provide the structural strength for tall walls, as well as the insulation needed, but I digress….

MODELLING METHOD

The third option is to contract a “Competent Person” to perform an energy analysis/model of the home showing it will meet/exceed the performance that would be achieved by a home built to minimum code standards.  For purposes of the Code “Competent Person” is defined as someone who is familiar and fluent with building design under Section 9.36.

 

As you can see, Section 9.36 will result in a significant change to the Saskatchewan building industry.  This is a change Prairie ICF has been anticipating and researching for several years, so if you have any questions please feel free to CONTACT US.  Luckily, NUDURA’s products are able to exceed the prescriptive requirements of the Energy Code with no need to invest additional time/money into Trade-offs and/or energy modelling services!

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