Feasibility Check
Side Addition
These are units built by building a new self-contained unit in an addition at the side of your house. To register your unit legally, there are some specific requirements you will need to meet. The city refers residents to this Ontario website for a detailed guide for checking these requirements.
Click here to learn more. Before you review the information provided by the Ontario website guide, check out our checklist below as a starting point to see if your home is a candidate for this kind of new suite. Remember to verify all code requirements with your local code, or hire a professional to do this for you!
Spatial Requirements
Check to make sure you have a room for an addition
>>Look up your property
Side and rear yard setbacks are specific to different neighbourhood zones. You can look up your property’s specific zoning regulations using this map.Here’s a video that explains how to use the city’s map website. If you have trouble navigating, ask a professional for help!
Side and rear yard setbacks are specific to different neighbourhood zones. You can look up your property’s specific zoning regulations using this map.Here’s a video that explains how to use the city’s map website. If you have trouble navigating, ask a professional for help!
>>Check the sideyard setback
Once you locate your property on the zoning map, you can find a link to the zoning rules for your prperty. This will tell you the allowable setbacks and other regulations. You can also use a measure tool to check the size of the building or other dimensions. Here’s a video that explains how.
Once you locate your property on the zoning map, you can find a link to the zoning rules for your prperty. This will tell you the allowable setbacks and other regulations. You can also use a measure tool to check the size of the building or other dimensions. Here’s a video that explains how.
>>Check if you have space for a side
addition
After you find your sideyard setback requirement, find your side property line, measure the required setback distance from it, and then measure the distande from that point to your home.
This last number is the space you have to build. If you’re going to make a stand-alone unit. If you only have 2 or 2.5 meters, you may be able to squeeze in some sort of micro unit. 3M is an ideal width to fit a more typical unit.
After you find your sideyard setback requirement, find your side property line, measure the required setback distance from it, and then measure the distande from that point to your home.
This last number is the space you have to build. If you’re going to make a stand-alone unit. If you only have 2 or 2.5 meters, you may be able to squeeze in some sort of micro unit. 3M is an ideal width to fit a more typical unit.
>>Check for protected trees.
If your answer is yes to either of these questions, your trees require protection. Look up the required dimension for the required Tree Protection Zone around each trees New construction should stay out of this zone, otherwise you will need to apply for a permit to injure or remove your tree.You can find more information on tree protection zones, and permits for injuring or removing trees on the city’s website.
- Are you in an area protected by the Ravine and Natural Features By-law? Check here.
- Are there any trees over 30cm in diameter?
If your answer is yes to either of these questions, your trees require protection. Look up the required dimension for the required Tree Protection Zone around each trees New construction should stay out of this zone, otherwise you will need to apply for a permit to injure or remove your tree.You can find more information on tree protection zones, and permits for injuring or removing trees on the city’s website.
Can you put in windows?
>>Natural light is a necessity for housing units. If your additional will block windows in the existing house, you may need to add new windows to replace them.
We recommend making sure at least 2 sides of your addition are at least 1.2m form the property line. This will make it easy for you to add windows. If your wall is closer to the property line, adding windows requires additional fire protection (like sprinklers or fires shutters) which can be expensive!
You may also need to provide a second exit through a window in your unit that is large enough for a person to get through and easily open without any tools.
Electric, Heating/Air, and Plumbing
Check Your Utilities
>>Check Your Electrical Service
1) Check your existing electrical service on your electrical panel
Find your circuit box. Find the main cut-off switch—this is typically the biggest switch in the box. The cut-off switch often has the number of amps written on it. You will likely need a minimum of 100 amps.
2) Use the chart below to calculate your existing electrical capacity (Coming Soon!)
3) Check how many units you can add based on your existing electrical capacity. (Coming Soon!)
Verify the level of electrical service you will need with a licenced electrical engineer or electrician.
Cost Considerations
Check to see if there are existing windows. And if there is ample space outside of the windows, this space is needed for emergency exiting. The Ontario website noted above provides specific requirements for these windows, but an architect or designer can help design this precisely.
- unit access
- fire and sounds separation
- site work
- new construction
- fire and sounds separation
- site work
- new construction
Case Study
The side addition case study involves adding a distinct living unit by building a new structure connected to the side of the existing strucutre of the house. The only changes made to the existing building are to the ajoining side wall which now acts as the fire separation and unit demising wall. Unit access to the side addition exists off the front of the addition. Major considerations include allowable building area, construction implications, and plumbing.
Existing Floor Plans
Preliminary Pricing
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