Project Specs

Location: Langley, British Columbia
Climate Zone: Cool-Temperate
Building Type: Single Family Residential
Project Phase: Certified
Certification Type: Passive House Classic
Year of Construction: 2019
Gross Floor Area (m2): 504.42
Treated Floor Area (m2): 432.9
PHPP Verification: Download

Project Description

Cairns Creekside is a charming modern farmhouse in Langley, British Columbia. The 2-storey multigenerational home is an impressive example of efficiency in design and energy.

Designed by DOS Design Group (formerly Draft On Site Services), the simple and charming modern farmhouse will house two families. As a result, the homeowners prioritized space functionality, overall comfort and long-term sustainability for their new home.

The home is designed to be a functional and comfortable space for two families. It features a master bedroom with ensuite on each floor, four additional bedrooms, a large family room with access to an outdoor living space, and spacious kitchen and dining area. The older couple will live on the lower ground floor, while the younger couple and their children live on the upper floor.

The long axis of the home is oriented westward from north to south to coincide with the natural contours of the land. Generous overhangs on the west façade protect from pervasive afternoon solar exposure. For additional solar  protection, a variety of high-performance glazing is used throughout the home. Every space also features large tilt and turn windows to provide effective natural ventilation; both interior and exterior shading systems will be used on all windows to further control solar heat gain.

The building envelope will consist of:

– R-28 Quad-Lock® Insulated Concrete Form below-grade crawl space wrapped with an additional 3 in. of EPS foam

– 2×6 wall assembly with R-20 batt insulation in the interior cavity and 6.75″ of exterior EPS insulation

– SIGA Majvest® facade membrane and SIGA Wigluv® adhesive tape

– Innotech Windows + Doors PHI-certified windows with true triple glazing

– Innotech Windows + Doors patio doors with Guardian Vacuum IG glass with nominal R-14

– R-76 net average roof assembly with blown cellulose and graphite-infused EPS

Some of the challenges were:

– The House was originally not designed to be Passive, instead it had originally been designed to meet basic Building Code requirements, however the Clients requested a redesign at the time of Construction to retrofit the design to be Passive

– The Clients were on a tighter timeline to complete, while working full-time jobs, so were not always able to respond in a timely manner, resulting in communication issues, however the project needed to move forward so there are a number of Construction Details that were changed mid-construction

– The Clients also started construction before the new design was started, let alone completed, so many aspects needed to be adjusted during construction

– Commencing construction prior to the new design being completed resulted in some of the Foundation work not being located in the most optimal position, it also resulted in the Foundation not being thermally broken from the surrounding land requiring there to be thermal accommodations made else where

– There is also the additional challenge that the Home Owner was overseeing the construction of the House themselves, in their spare time, and, even though the Home Owner is Passive House trained, not all of their Labour and Trades working on the Project were Passive House trained

However, all of this being said, we are very happy to announce that the House passed it’s Airtightness Testing with a rating of 0.3459. We also expect that the House will be reaching an approximate energy efficiency of 14kWh.