Jigsaw Homes - High Performance Home with Integrated Energy Generation

In order to meet the challenge of building a high-performance home at no additional cost, Jigsaw took a holistic approach to designing the home and its various systems. This included having the energy modeling process as an integral component of the design process. "It was in this way that we knew the implications from an efficiency standpoint of the design decisions we were making" says Cory Krygier, President of Jigsaw Homes. "We also brought many of the key trades into the process at a very early stage in order to engage them in the goals and solicit their expertise before decisions were made.

What Jigsaw found was that as certain elements of the home were reconfigured; other systems were affected. For example when Jigsaw determined that they were going to utilize a wall assembly with a high R-value, the need for a furnace to produce heat was dramatically reduced. The BTU heat loss was lowered so much, in fact, that the need for furnace was eliminated. The sole heat source for this home is water based and the water is pre-heated by a solar thermal system further reducing the overall cost for heating the home.

This re-allocation of the resources used to construct the home has enabled Jigsaw to keep a control on many of the costs associated with improving the home's performance. Jigsaw is working hard to continue tunneling through the cost barrier of building a high performance home. "We believe that at some point the increased costs of adding new technologies and ways of building the home will hit a point where the costs of construction will start to come down due to the elimination of some of the more expensive systems in the home," says Krygier.

Other ways Jigsaw is reducing the costs of the home include:

"Jigsaw set an EnerGuide target of 86 before incorporating any renewable energy systems in the home, adding renewable energy to the home, will take the High Performance Home to near-zero energy use", says Krygier, who is also a director on the board of the Net Zero Energy Homes coalition of which Jigsaw Homes is also a member.

Jigsaw's holistic approach to design and construction of the home balances value and performance, by paying equal attention to: comfort; health; durability while focusing on the performance triangle that includes balancing design with efficiency and cost.

Numerous features of the pilot project make this home energy efficient conserve water use and make it a healthier environment for the occupants. The highly efficient walls make the furnaces obsolete, and in its place, the home is heated or cooled by a small fan coil unit. This is coupled with an HRV (Heat Recovery Ventilation unit), which recovers up to 60% of the heat in the indoor air before exhausting it and also provides for several complete exchanges of the indoor air each hour helping to make the indoor environment more comfortable.

Jigsaw used several advanced framing techniques in the construction of the home to improve the envelope performance and reduce the amount of wood used in its construction. This includes the use of two-stud corners (see adjacent photo) and spacing the studs at 24 inches on centre rather than the more conventional 16 inches on centre. They estimate this reduced the lumber for framing by up to 15%. A superinsulated 10" frost wall was used in the basement with an R-value approaching R40. (R or SI values, are a way of labeling the effectiveness of insulating materials, the higher the R value or RSI value, the more resistance the material has to the movement of heat). This is a relatively inexpensive way to improve the envelope performance without adding to overall costs. In addition to the super-insulated walls Jigsaw installed 4 inches of rigid foam insulation under the slab to prevent the thermal bridging that generally occurs between a concrete basement slab and the ground below. In addition this insulation was placed over top of the footings to ensure the thermal bridge was broken right to the edges of the slab.

The home boasts several features designed to reduce water usage some of which include dual flush toilets, low-flow faucets and showerheads and a water circulation pump. The water circulation pump is a low energy pump that circulates hot water through the water lines on a timer ensuring that hot water is delivered to where it is needed without the need to run the water for more than a few seconds. Some estimates, according to Jigsaw, have the water wasted (while waiting for hot water) at between 25,000 and 30,000 litres per year for a family of 4. By incorporating this simple pump the savings on the water is significant.

The home also has a solar thermal water system on the roof, which pre-heats the water that is then run through a 98% efficient condensing tankless water heater. In the middle a cold Calgary winter on a sunny day it is possible for water in the preheat tank to reach temperatures of 60 degrees Celsius. The preheat tank is located in the mechanical room and is always at room temperature at the least further reducing the heating load on the tankless water heater. Jigsaw has also pre-wired the home for future photo-voltaic panels, although the current incentives or rebates in the Alberta market make the installation of these systems too expensive for the time being. Currently the only real government incentive for high-performance homes is up to $10,000 in rebates for reaching an Energuide rating of 86. By being solar PV ready, Jigsaw has built-in the flexibility for the house to incorporate this system when they are more cost effective.

For the near net-zero home to be near net-zero, the occupant must interact with the home's energy management system. "Jigsaw's High Performance Home monitors up to 10 circuits, providing real time energy use data to the occupant, the moment they turn on the television for example, this system will let the homeowner know how their home is working," said Krygier. "Education is a big component in our holistic approach, in that we teach the home owner how to live in the home so that they better understand how their actions impact the homes overall performance."

The first pilot project has been under construction for 6 months and completion is anticipated in early March. Jigsaw believes this time period will be reduced as these homes become better understood and the trades get more accustomed to building them. The project was in the design phase for about 4 months. While Jigsaw did not encounter any resistance to the project from the city planning department they have had some resistance from the building inspectors on the site. "It will be more and more important for the building inspectors and municipal authorities to learn and stay informed about the various components of a high performance home in order to get these homes built."

Jigsaw's long-term vision for these high performance homes is to see thousands of units like these being built across the country. Jigsaw is planning to be an integral part of this process by leveraging their expertise and product to facilitate these homes being constructed in other cities. "If these homes work in Calgary, they will work in most markets across Canada and in many other cold climate locales in the United States as well," says Krygier. "We want to continue to be at the forefront for the development of these homes helping to create improved market demand for the high-performance home." For more information, please visit Jigsaw Homes.