The Smart Sustainable Resilient Infrastructure Association (SSRIA) is here to present its Green Building Technologies Network (GBTN) Spotlight Series. This series will be featuring a project team once every month until March 2023. The aim is to get to know the projects and teams working in the GBTN and support further collaboration, communication, and knowledge sharing among our members.

Our guest this month is Homes by Sorensen, welcome!

Project Type: Multi-Generational Residential New Construction

Project Aim: Affordable Net-Zero Multi-Generational Home

Project Summary: Click here for the complete project summary

Homes by Sorensen is a home building company operating since 2009 that focuses on sustainable building and custom quality homes with an ambitious goal of becoming Calgary’s leading net-zero home-builder. With a strong modus operandi of helping the industry move forward.

We are happy to have Homes by Sorensen with us for our Spotlight series, Calgary’s up-and-coming green home builder dedicated to enhancing clients’ lives and building high-performance homes that make this world a better place. This month we are spotlighting the SSRIA GBTN testbed project Project Leo. The project features innovation in multi-generational net-zero design for residential homes. Here’s what Homes by Sorensen joint owner Axel Sorensen and Homeowner/Consultant Glenn Harasym have to say.

What is a multi-generational home and what were the greatest challenge in design decisions and integration of passive strategies on it?

A multi-generational home is a home where more than one generational family lives under the “same roof”. Technically we don’t live under the exact same roof as we are adjoining similar to a duplex. The difference from a duplex is that we share a mechanical room/utility hook ups and have a space that adjoins the houses, but creates privacy. The primary difficulty of integrating passive and multi-generational was in finding a team that we felt was qualified and willing to take on the Project. The degree of pushback from industry professionals was very difficult to deal with. We still get quite a few comments of challenge on the success of the project and the cost from the general public and industry professionals alike. We definitely get substantially more interest then pushback, but it is interesting how polarized the opinions are. I also think Calgary’s urban layout creates challenges. More affordable central city (near downtown) properties are primarily east west facing. The stacking of the houses allowed for Passive principles to be integrated into both units. However, a side by side orientation would make this much easier. To me, it brought up the question as to whether urban planning is the largest factor inhibiting the large scale successful implementation of this building type. I think there is a real opportunity for new housing developments to integrate some of these principles in creating better products for the same money. -Glenn Harasym (Homeowner)

The biggest challenge was sorting out a good sound proof design for both homes. Because that design was a side by side, we needed to make the back unit a second story so they would have a southern exposure to their suite. – Axel Sorensen (Homes by Sorensen)

What considerations have been made to promote the replicability of future multi-generational passive houses in the context of buyers as well as builders? (ie. what will motivate more home owners to go this route?)

Obviously the shared costs of the project and the overall feasibility of it will motivate people to go this direction. – Axel Sorensen (Homes by Sorensen)

I would argue that the primary motivators to buyers would be that you can achieve this degree of quality for the same, or almost the same, monthly cost as conventional builds. You just have to integrate some key planning principles in the very early stages of design. The added benefits are a higher quality build (i.e. less repairs) for your largest investment, higher environmental comfort, a better feeling about your impacts and less monthly fluctuation in cost. For builders, we planned the house to utilize industry standard building techniques where possible. We then focused checks and training on areas where non-standard techniques could cause errors with large implications to timelines and costs. The ability to be involved in a project like this offers a degree of unique marketability to these companies. Especially with likely upcoming changes to building codes over time. We think some people believed that these techniques were only usable in high-performance homes, but some could be implemented for little to no cost in traditional builds to create better energy efficiency and lower bills for owners. -Glenn Harasym (Homeowner)

The project also focused on a cradle-to-grave approach to quantify GHG impacts through the life cycle of the building with pre and post LCA analysis on materials and operations emissions. What is a cradle-to-grave approach and how does Life Cycle Analysis help us get there?

The amount of buildings we construct and use, and the opportunity to lower environmental impacts for these buildings, creates a massive opportunity for reducing our overall environmental impacts in North America. This is known as cumulative impacts, and in the environmental science world, it creates really great opportunities. A cradle-to-grave approach is the idea that impacts should be assessed through the entirety of a products life rather than just during operation. For example, a car does not just create impacts when you drive it. It creates impacts when resources are gathered for its production, during operation, during maintenance and when you dispose of it. Understanding these impacts vs benefits is a much better way to make decisions as we can focus on fast cheap changes, for things we use a lot of, to make massive overall impacts. -Glenn Harasym (Homeowner)

For energy monitoring you have included a Sense Solar monitoring system. Can you explain in simple terms how the energy Sense Solar Smart energy monitoring app works that you have installed for the house ?

Yes, the Sense Solar energy monitoring system works by using lead clamps that measure the amount of electricity that flows through a wire. There are two sets, one that measures the in flow of electricity into the house and one that measures the amount of electricity being generated from the inverters coming into the home. With these two measurements, we can tell what their overall usage and production is for the year (ie whether they actually operated at net zero for the year). We can also see how much of the homes usage was directly powered by the solar and how much was exported and imported back when needed. This is all available to view on an easy to use app for your smart phone.- Axel Sorensen (Homes by Sorensen)

The app is actually what I consider to be one of the best “bang for bucks” that we installed. It uses a really simple system for remarkably easy integration with any home. Amazingly, over time the app uses AI technology to identify unique energy signatures for your house and identify appliances. It automatically tells you the percent increases per day/week/month/year and what your phantom energy use is. -Glenn Harasym (Homeowner)

Project innovation included overall design and wall assembly with consideration of upgraded mechanical choices (and sharing between the two units) to achieve cost savings and lower embodied GHG’s. Was there any additional innovations and takeaways you wish you could have applied or that you specifically really like?

I really like that our floor systems on this project had really great thermal breaks from the outside. This is a technique I am using on future high performance homes. The mechanical wall (third wall) is my biggest take away as a question mark. The third wall really made the constructability of this home lower than I would have liked. The real purpose behind it is to prevent your air barrier from being harmed by penetrations. I have produced better results without this method in terms of air tightness. You can make the argument that the air barrier will not be harmed by hanging pictures and such over the years, but is that really worth the added cost of the third wall? That is a large takeaway question for me. One that I would currently answer with no.- Axel Sorensen (Homes by Sorensen)

In general, I am very happy with the choices we made. The only thing I wish we would have done differently is to plan for optimization of the solar layout during the initial design phase. In hindsight, I would have focused more planning on ensuring no obstructions were located on the major south facing roof for the top unit, and extended the gables to allow for more panels. Our panel system has individual monitors and overall monitors for the front units system (which faces east/west and has more shadowing) and the back unit (which is south facing and has less shading). It is very interesting to see the differences in these panels production and the differences in snow melt time between panels. It creates a significant opportunity for cost savings, greater efficiency and reduced embodied GHG’s. -Glenn Harasym (Homeowner)

In June, Project Leo participated in the Eco-Solar Home Tour, how was the project perceived by visitors what did comments and reviews of the project reveal?

I think overall people really like how simple the home was as well as how aesthetic it was for a high performance home.- Axel Sorensen (Homes by Sorensen)

Generally the comments and reviews were quite good. The YouTube videos were quite interesting to watch in that opinions have been polarized. In general though, we have received a lot of interest with some people potentially wanting to recreate the build. The main thing that seems to resonate with people is the multi-generational living and the cost per month arguments. We have locked in for a 10-year mortgage. When you subtract our principle and compare it to when we were renting, we are paying less per month for twice the square footage, in a brand new net-zero house, with a property value that should elevate over time. The argument that you are paying more up front, is not as relevant as people think when you explain it to them in cost per month. -Glenn Harasym (Homeowner)

What advice do you have for other homeowners endeavouring to duplicate the concept you have with Project Leo and how important was the homeowners disposition in making this possible?

My advice would be to consult a high performance designer/builder as early as possible in the process and to make sure the families of the future multi generational home are in agreement of what they would like the project to be. Our homeowners were very good this way and got a great result because of that.- Axel Sorensen (Homes by Sorensen)

I think their were a few key principles we used that made us very successful. 1) implement passive concepts. You don’t need to be passive, but using the physics is free. 2) plan early for net-zero. It is hard to keep costs down if you don’t have net-zero as one of your initial priorities and understand how other changes effect it. 3) Keep things simple. Less corners, a less complicated roof and a less complicated mechanical system make things way easier and cheaper. 4) Find a good team. You need someone who understands the techniques and the vision. 5) Prioritize your rooms and your goals and put most of your money in the things that matter to you. Opportunities to make things “nicer” will always pop up, but they likely won’t be worth your money unless you understand your priorities. -Glenn Harasym (Homeowner)

How much is the additional cost as estimated by Homes by Sorensen to move a baseline home towards a Homes by Sorensen Net-Zero, Low energy Plus Passive House?

We are finding that net zero and passive homes are costing an additional 7-12% extra.- Axel Sorensen (Homes by Sorensen)

We are approximating 11% right now. That is calculated including land. Though this may seem high to some, and low to others, I think the key thing, is that with current mortgage rates, the cost per month is the same. It is very dependent on making sure you follow some key principles and plan early though. There is definitely a potential for a houses cost to balloon. Following principles and establishing the right checks at key areas is important. -Glenn Harasym (Homeowner)

You have completed the second milestone of the project which means that the construction of the house is already complete. What learnings did you take away that could make the next home even more affordable, even more efficient?

If I was to do this exact wall system again there would be little tweaks that would make it go more smoothly. My time to design it would be easier with now having the experience. Every time I build a high performance home I fine tune my ideal high performance home. This home being a passive home exceeds that as passive homes are focused more on performance rather than cost efficiency. But it was easy for me to see small details that are easily added to even code built homes but at very small costs. Overall, the experience I gained from building this home will better equip my company to provide better and better homes – Axel Sorensen (Homes by Sorensen)

We are currently monitoring the benefits of the Sanden system. The hydronic coil seems to offer some great energy savings and so focusing on the proximity of the hot water tank to the HRV system is something that we would have changed. Additionally, an in depth early planning and mapping of solar would have create a significant difference. Overall though, we are very very happy with the product (98%+) and would be crazy to nitpick what we achieved. -Glenn Harasym (Homeowner)

In your view, what will be the greatest reward or take-away from this project?

Overall, the experience I gained from building this home will better equip my company to wider range of performance to people looking to build high performance homes. The more experience I gather the more efficient I will become at delivering these, thus decreasing costs and educating my trades along the way. Our main goal as a company in regards to high performance home building is to bring these homes to the masses and help move the industry towards them. This experience is one more step in the right direction.- Axel Sorensen (Homes by Sorensen)

I think people are looking at the environment with this very 0% or 100% lens right now. Either you use nothing or you use everything. You have a solution that completely fixes human caused global warming or you don’t. In reality the solutions are a lot more grey and have a lot of factors. I think it has been interesting to see peoples opinions, but also to see that people think of Passive House in this 0% or 100% way. In reality, I don’t think certification is as good of a solution as just using the general strategies as best you can. The same strategies could be used in conventional builds to very impactful energy savings for no increased cost. Money is the primary argument against creating solutions that lessen our impacts and it is a good one. We need to take it seriously because the cumulative effects of the changes could be significant. -Glenn Harasym (Homeowner)

For more information on this project, visit their project page here.