What is the approx cost to convert garage (20 x 24) in a bungalow into living space (with basement), and build out garage?
While I couldn't possibly quote your project in Ottawa over the internet from here in Toronto, I can tell you that there are a lot of things to factor in to what you are proposing.
You will need drawings done.
If you are putting a basement under the converted space you are talking about demolishing the existing structure unless the garage is integrated into the bungalow and not simply attached in which case the costs would go up dramatically.
Are you planning on running plumbing out to the new converted space?
If so, you will likely be breaking up your existing basement floor unless you are lucky enough to have a plumbing stack in close proximity to the adjoining wall. In any case this will likely affect existing finishes (if any) in your current basement.
With the size you mentioned and a basement, you are talking about adding over 7,000 cubic feet of volume to your home (assuming 8' main floor and 7' basement). That will quite likely require upsizing your HVAC equipment. Regardless you will need a Heat Loss/Gain calculation and HVAC design done for the HVAC permit.
While I cannot speak for anyone else, I would suggest inviting a few Contractors in your area to visit your home and discuss the details of your plans from which they could produce a much more reliable estimate.
Projects like that can add a lot of value and often much needed living and storage space to a home.
Best of luck on yours.
Cedarfalls Building Consultants Limited
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