Decoding proposed building height amendments
March 10, 2015 - On March 24, you will have an opportunity to speak with the Executive Committee of Council about the proposed bylaws which would change how we measure the height of buildings and in some cases, increase the size and height of buildings.
Perhaps you have reviewed the proposed bylaws but you are not sure what it all means. Read on to get an explanation of the present and proposed methods of measuring and regulating height. Think about the consequences and share your thoughts with city council on or before March 24.
The existing Zoning Bylaw regulates the heights of buildings through:
- Maximum number of storeys
- Maximum height of the roof midpoint
- Maximum height of the roof highpoint (ridge/peak), and
- Grade – the base from which the vertical distance (height) to roof midpoint or ridge are measured.
In brief, Part 1- Bylaw 16733 eliminates the number of storeys as a height limit, and increases the maximum roof midpoint height of low-rise apartments (RA7) and general business zone (CB2) from 14 m to 16 m. Part 2 - Bylaw 17062 clarifies how the midpoint of roofs is measured and eliminates the limit to roof ridge height.
What are the potential impacts of these amendments?
Eliminating Maximum Storeys
Eliminating the maximum number of storeys allowed in a zone does not impact the permitted height of a building. However, it will impact the allowed size of buildings in the zones for small scale housing. These buildings have always had a limit of 2.5 storeys. By eliminating storey restrictions, the 2.5 storey buildings could become full 3 storey buildings outside the Mature Neighbourhood Overlay (MNO) area and a nearly full 3-storeys within the MNO area. Key word for those living in MNOS being "nearly."
The MNO has special regulations which restrict the half storey to 50% of the second floor, and restrict the maximum height of basements to 1.2m out of the ground. These regulations were introduced in order to preserve the mature neighbourhood character. The proposed amendments delete these regulations. The regulations could be kept at least until there is a comprehensive review of the MNO and public consultation.
Removing storey regulations provides more flexibility in interior housing styles, such as split levels, walk-out basements or raised basements. It allows development of additional floor space without increasing the highpoint of buildings.
Maintaining Maximum Height to Midpoint as the key height measurement
The maximum height stated for each zone continues to refer to the vertical distance from Grade to the midpoint of the roof for all styles of non-flat roofs.
Some cities measure only the height to the highpoint of the building. This method encourages boxy or flat roofed buildings. Measuring to the midpoint encourages a variety of roof styles.
Removing storey limits to low scale housing will make mansard-style roofs more attractive, because this style will allow nearly as much floor space as flat-roofed buildings on the top floor, and can be built higher than flat-roofed buildings because the height limit is to the midpoint of the roof rather than to the deck - top of the roof. For this reason, Ottawa measures the height of mansard roofs to the deck, and Edmonton could do the same.
Increasing midpoint height
This round of amendments primarily deals with how height is measured. However, there are two changes to the maximum midpoint height being proposed - both the height of low-rise apartments (RA7) and general business buildings (CB2) have heights being changed from 14 m to 16 m.
This change would allow four-storey buildings to have higher ceilings and a sloped roof. Alternatively, the buildings could have five floors with 8-foot ceilings and a flat roof. The space could be used more efficiently. On the negative side, taller buildings create more shadow, massing and to some extent more wind.
Eliminating peak height limits
Currently the ridge or peak of a roof can be a maximum of 1.5 m above the maximum permitted height of the roof midpoint.
The proposed amendments eliminate the highpoint (ridge/peak) height. This dramatically increases the potential ridge height.
For instance, a semi-bungalow in a mature neighbourhood can presently have a roof extending to a height of (8.6m to midpoint +1.5m=) 10.1 m at the top ridge. Whereas with the proposed amendment, the ridge could extend to 13.2 m. More dramatically, an A-frame building in a mature neighbourhood could have a peak over 16 m in height. In both cases, the neighbours and leagues do not have to be notified of the appeal period for the development permit because the heights would be permitted according to the amended Zoning Bylaw.
Eliminating the limit to the highpoint of roofs creates a wide range of possible peak heights and much uncertainty.
The Zoning Bylaw presently states that Development Officers shall determine Grade by one of three different methods or they could create their own method. These varied options create inconsistent Grade measurements. However, the most common way of measuring Grade is taking the average elevation of the property corners.
The proposed amendments add one more option for calculating Grade. For sloped properties where the rear property line is at least 2.0 m lower than the front property line Grade is calculated by the average elevation of the front corners of the lot and the points at the front setback in the underlying zone. Thus the Grade elevation is determined solely by the front street level.
This additional Grade calculation, plus the elimination of storey limits, allows walkout basements of two storey buildings without having to get a variance. Wow, there are many proposed amendments to the Zoning Bylaw in order to make an application for a variance for walkout basements unnecessary!
EFCL Planning and Development Committee suggestions
At this point in time, the Committee is suggesting that, a) a maximum ridge height be maintained, b) mansard roofs be measured to the roof deck, c) 14 m maximum height of low rise apartments be maintained when next to lower buildings, and d) regulations in the Mature Neighbourhood Overlay be maintained until a complete review and consultation has been completed.
The Committee wishes to get more feedback from leagues prior to making any comments on eliminating storeys and other amendments. Please forward your comments or questions to your EFCL District representatives or to email@example.com. Upon request, diagrams illustrating the potential impact of the amendments will be forwarded to you.