Compared to an OBC required envelope, develop a high-performance envelope at least incremental

The following is based on a square 2-storey building, plus basement, with 10 m per side, 2.5 height
per floor, with basement floor being 1.5 m below grade.

Design the following typical building assemblies as OBC compliant and high-performance while
controlling moisture:
Roof (100 m2, attic or flat roof)
Above grade wall (260 m2, including windows)
Glazing & overall window (window area 25 m2, average window size 1.5 m2)
Below grade wall (60 m2)
Basement slab (100 m2)

For the high-performance cases, thermal bridging is to be minimized by design.
For the high performance cases, assume a tested airtightness of 1.0 air change per hour (ACH) can
be achieved.
For below grade walls and slab the control of the water table and proper drainage needs to be
For the areas above, calculate the OBC compliant design day heat loss for Toronto. Develop two
high-performance thermal envelope cases which meet an overall envelop heat loss of 5 kW.
Winter Indoor conditions are 21C and 40 % RH (relative humidity).
Summer indoor conditions are 25C @65% RH (for summer moisture considerations in basement)
Deep ground temperature is 10C.
At least the following topics should be adequately covered in the assignment report:
List of components or labeled graphic of each opaque wall assembly
For whole opaque building assembly, calculation of effective R-values
Calculation procedure for below grade heat loss.
For glazed areas, glazing and whole window characteristics and R-values
Cost of assembly per m2 and of whole building for each case
For each assembly, calculation for locating dewpoint, and location and type of vapour
retarder (barrier)
For each opaque assembly locate the air barrier(s) and discuss/illustrate how these are
made continuous at window openings.