As Calgary’s premier backyard suite builder, we get asked every week by potential clients about the possibility of building a new suite on top of an existing garage. It may be because these people have a new garage and feel it would be a waste to tear it down, or perhaps they have built a reinforced pad and structure and think it is more than capable of accommodating a new construction project above.
Unfortunately, in all situations, you cannot build a new “suite” on top of an existing garage in Calgary due to the structural engineering requirements and building code regulations associated with this type of residential construction. Also see:
- Tips for Hiring the Right Garage Suite Builder for Your Project
- Backyard Suite Utility Connections: 10 Questions & Answers
Engineering Requirements
Garage suites are carefully designed so that the foundation and structure are strong enough to support the weight of the suite above it.
Each backyard suite has a joist/truss layout designed by an engineer who carefully calculates the loads associated with the garage suite structure and ensures they comply with local building codes. These joist/truss systems are engineered for both the foundation, mid-floor, and top roof. If the suite also has a tall wall, that will be part of the suite’s engineering.
If the garage suite has a basement, the engineering will be more heavy-duty, as the floor will have to support the load of cars above. For your information, we have never built a garage suite with a basement to date, due to the high costs associated with such a design.
Alberta Building Codes & Standards
Another reason why you can’t build a new suite on top of an existing garage in Calgary is because of the building codes and standards set out by the provincial regulator.
Such regulations stipulate requirements for minimum roof and wall insulation ratings, ground frost wall depth, and structural maximums/safety load capacities, the last of which directly prevents the construction of a new suite on top of an existing structure.
The development permit process ensures that new construction will not occur on top of an existing garage. The City of Calgary, for example, will not approve any permit to perform such an action because it is illegal.
National Energy Code of Canada
A third reason why your garage and pad must be demolished before building a new backyard suite in Calgary is the National Energy Code of Canada (NECB), implemented nationwide in 2017.
The federal government developed the nationalized code as part of Canada’s commitment to improving the energy efficiency of buildings and reducing greenhouse gases (GHGs). The NECB covers a full spectrum of building components and systems, including the building envelope, electrical, and mechanical systems.
Hence, it would be incredibly difficult to modify an existing garage that would meet both provincial and federal building codes. Actually, let’s just not go there at all!
Engineered Foundations
In some instances, homeowners may have been planning for a garage suite in the future and built a garage with an engineered foundation to accommodate the suite construction at a later date. While this is a great way to plan ahead, we’ve been approached by several homeowners to take on such a project where we would build on top of an existing garage. We do not take on such projects for several reasons:
#1 – Despite having an engineered foundation and stamp, we do not know precisely when or how it was built which creates uncertainty around the structural integrity, as we have not performed the work ourselves.
#2 – Deconstructing a finished garage to build a second floor would introduce unnecessary complexity to backyard suite construction that our company is not willing to take on.
#3 – Building on top of work performed by another builder will often void insurance coverage; therefore, the risk involved is often significant and complex to navigate from a logistical viewpoint as well
Overall, while it is possible to build a garage suite on an engineered foundation with a stamp, we do not take on such projects and prefer stand-alone new single builds.
Want to Build a Garage Suite in Calgary?
The great news is that all demolition associated with any garage suite project we have is included in our pricing. That means you don’t have to worry about paying extra for these services!
Contact us anytime at 403-797-4918 if you have questions about building a backyard suite in Calgary and we will be happy to assist you! We are looking forward to discussing your investment goals with you!
