COMMERCIAL HIGH RISE BUILDING DESIGN -3

COMPONENTS OF HIGH RISE BUILDINGS

1. PODIUM

2. TOWER

3. BUILDING TOP

The built form and massing of a tall building has three main components that are integrated in the whole of the design. Depending on the design style, function, use and context there may be significant or subtle differentiation in the character or detailing of each of these segments

1. PODIUM

The podium (or building base) is the primary interface between the tall building and the surrounding streets and public spaces. It therefore has the greatest impact on how pedestrians interact with the building and how the building fits within the street level environment.

Podium Location:

The podium shall be located to frame the street.

Continuous street walls are generally desirable, except where special site or block conditions require breaks to access mid-block connections, public courtyards, or other open spaces.

Podium Height and Massing:

The maximum height of the podium shall be 80% of the adjacent right-of-way width. A maximum height of 20 metres is recommended to maintain a human-scale.

Above the podium, step backs should be provided on all sides to clearly differentiate between the building podium and tower.

Shadows/Sky Views :

As a rule-of-thumb, the height and massing of the podium (not including the tower) shall ensure a minimum of five consecutive hours of sunlight on the opposite side of the street at the equinoxes (March 21 and September 21).

Podium Design & Articulation:

The use of ‘heavy’ materials (i.e. brick, stone, or metal) should be used within the podium to anchor the building.

Large podiums shall be broken into smaller components both visually and functionally.

Mixed-use podiums shall reflect multiple retail units, while residential buildings shall provide individual entrances for ground floor units.

2. TOWER

The tower is the most substantial and impactful component of a tall building. It enhances the skyline and provides a defining landmark throughout the City. The design and massing of the tower should recognize and reflect this important role, and should be carefully considered to minimize adverse impacts on adjacent neighbourhoods, parks and open spaces. The tower should maximize sky views and access to sunlight through slender floorplates and spacious setbacks between towers.

Tower Location

The placement of the tower shall have no substantial impacts on adjacent Residential Neighborhood Areas, parks, open spaces, or natural areas.

Where multiple towers exist on a site, they shall be arranged to provide a gradual and appropriate transition in height to adjacent established or planned uses.

A minimum separation distance of 25 meters shall be provided between towers to maximize privacy and sky views, and to minimize the cumulative shadow impacts of multiple tall buildings. Balconies shall not be provided within this separation distance.

Where no towers currently exist, proposed towers shall be set back 12.5 meters from adjacent property lines to protect for a future 25 meter separation distance (split between each property).

The tower should be stepped back at least 3 metres from the podium to differentiate between the building podium and tower, and to ensure usable outdoor amenity space (i.e. patios).

For design flexibility, a portion of the tower (i.e. up to 20%) may extend to the edge of the podium without a step back provided it can be demonstrated that there are no adverse wind impacts.

Tower Height and Massing

The height of the tower, and its location on the building base, shall provide a gradual and appropriate transition in height to adjacent established or planned uses. Where multiple towers exist on a site, this transition shall be reflected across the entire site.

The transition of building heights is meant to protect stable low rise residential areas. The next level of building height is mid-rise: A mid-rise building should be separated from the property line of a neighboring low-rise residential building by a minimum of 7.5 meters, which may include a lane. A 45 degree angular plane should be applied to determine setbacks as well as the maximum height of a building according to its distance from the nearest property line of a low-rise residential lot.

Tower Design and Articulation

A variety of techniques shall be used to articulate the tower, both vertically and horizontally, to create visual interest and encourage unique designs.

All sides of the tower shall be constructed with the highest quality of architectural design and materials.
Lighter materials, such as glass, are encouraged in the design of the tower to minimize the perceived mass.
Balconies are encouraged within the tower to provide amenity space and additional articulation. They may be inset or extruding, but should be a minimum of 1.5 metres to provide usable outdoor amenity space.

Slender point towers with compact floorplates are preferred in order to:

Maximize views, light and ventilation for the interior spaces.
Facilitate views of the sky and sunlight reaching outdoor spaces.
Avoid the perception of a canyon effect along streets and sidewalks.

Create narrow shadows that track quickly across the ground; and afford opportunities for views and vistas of landmarks and natural features

3. BUILDING TOP

The top of the building terminates the tower and adds visual interest to the skyline. A unique design assists with way finding and orientation in the urban environment.

Rooftop Design and Articulation

Design the upper floors of tall building to clearly distinguish the top of the building from the tower, to further reduce the building profile, and to achieve a distinct skyline. This may include stepbacks, material variations, and/or unique articulation.

Where the design of the tower itself is unique, and creates an interesting and varied skyline, a clearly distinguishable top may not be required.

Where located at a gateway intersection or terminating view, the tower top is encouraged to act as a recognizable landmark with signature features defining its importance.

PUBLIC AND PRIVATE OPEN SPACE

Typological use of the deck

The use of the deck is to create artificial ground space over the natural ground level. It is to provide additional space to accommodate some activities that would be accommodated at the ground level.

Especially, in a highly condensed site situation, this deck space gives more rooms to adopt numerous street and ground level activities.

Based on the purpose of its intended use, the deck structures can be defined into different types. However, in all types. a deck carries two main basic functions.

It provides a,