Landscape Hardworks

The overall landscape conceptual design with defined landscape zones is to be developed by the Landscape Architect in conjunction with the Project Design Team.

• Carefully consider location where retaining walls are necessary to meet site development parameters. 
• Retaining walls may be incorporated under the edge of the building slab, to simplify providing acceptable surface grades and positive drainage. 
• Walls adjoining grass slopes, batters or garden beds, should include a return.
• If retaining walls are located close to covered ways or roof overhangs they must be minimum 2.0 metres (horizontally) away from the roof edge to inhibit access onto the roof.                             
  Refer to DG / SAFETY (ACCIDENT AVOIDANCE) & GENERAL SECURITY
• Construct retaining walls in concrete or masonry (concrete blockwork, brickwork)
• Heights should be limited, if possible, to 1.0 - 1.2 metres (maximum) as this constitutes a reasonably economical solution.

Note that DoE requires a balustrade wherever level change exceeds 300mm, including level changes in external areas.

• Timber retaining walls are NOT considered acceptable as they can deteriorate quickly and occur a higher maintenance cost . (unless approved by the client for exceptional circumstances).

• Seating steps where appropriate, should be considered as an alternative method of retaining level changes.
• The design of the seating steps is similar to that of tiered seating as nominated within the Building Code of Australia Section H1, as such should be designed to meet the requirements of the BCA.
• Subject to the land slope and available area, the preferred dimensions for external stepped seating are:
• Risers   300mm (Primary) – 350mm (Secondary)
• Going   800mm (Primary) – 900mm (Secondary)
• Intermediate access steps (preferably at the ends of seating rows)
• Risers   ½ seating riser
• Going   300mm (min.)
• Width    900mm (min.) (size to suit estimated traffic).
  Refer to DG / SITE FACTORS / CIRCULATION /WIDTH FOR MASS MOVEMENT
• ​Top seating step should be at least ½-seating riser above ground level behind and 450 – 600mm wide.
• To shed water, provide at least 10mm fall across each seating row.
• Stair handrail to be provided to outer side of access steps.

Tactile indicators will be required to the top and bottom of external seating steps.

91.05seating1.jpg

 

• The Preferred pavement material for pedestrian areas (walkways, ramps, spaces between buildings, COLA) is concrete with:
  • ​Coloured concrete to Assembly Area to reduce glare.
  • Plain concrete to walkways.
  • Broomed finish to provide a non-slip surface. 
  • Different colours are acceptable in large patterns in the Assembly Area.
• Recommended Falls

     Minimum gradient of concrete paving           1:50 or 2 % (recommended to minimise ponding).

     Max crossfall (flat path/walkway)                    1:50 or 2 %

     Max crossfall (sloping walkway/ramp)          1:100 or 1 %

• Exposed washed aggregate is not a preferred finish. 
• Asphalt concrete (hot-mix bitumen, black top) while not generally recommended for pedestrian access in schools, where it is installed, have:
  •      Min. gradient required  (to prevent ponding)  1:35 or 2.8 %
  •      Max. cross fall in parking areas  1:20 or 4 %
• Unit paving (interlocking concrete pavers) may be appropriate in areas with highly reactive soils.
• Brick paving or other unit paving may be installed to an area up to 2.0 x 2.0 m around the base of trees in high use areas
• Gravel (including decomposed granite paving) is not considered acceptable for reasons of safety, within 10 metres of circulation routes.
• Consider the use of permeable pavements such as bonded gravel to tree surrounds