Drop Edge Beams

If you want to build your new home on a slope you may need to have the additional cost of needing drop edge beams on the low side of the slabs.

These are a sort of retaining wall to hold the fill under the house slab as shown in the drawing below.

Here is a photo of a typical drop edge beam before the brickwork has been started.

Costs (2013) are in the order of $500-$700/sqm of beam, plus the cost of the fill under the slab.

Say. . . $12,000 to $18,000 for a 20m long house with a 1.5m drop beam so a significant extra!

The photo below shows the same wall after the brickwork has been completed.

If you are building on a slope you may also want to know about Retaining Wall Fairness

Thanks to Grumblebum54 for the photos

Restricted Site, Costs

People are astonished at how the builders costs soar when building on a restricted site!

A restricted site is generally when a the building takes up most of the block. Generally this means that there is little room to store materials and special techniques may be needed to construct the house.

Generally if you are on a new subdivision you should be able to avoid  restricted site costs but if you are looking to build in an existing suburb, particularly something like a Battle Axe block, then there is a good chance that you will be hit with the extra charge.

Here are some of the reasons why it can costs extra:

Double Handling, If all there is limited space for storage on site the builder may have to store some of the materials at his own yard. He then has the additional cost of reloading the material onto his truck and delivering to site.

Smaller Deliveries. When you buy building materials the charge is normally based on the cost of the materials and the cost of delivery. If you need 2 or more smaller deliveries rather than 1 the cost is going to go up.

Different Construction Machinery. In some cases the contractor may have to use smaller, less efficient, excavators. For really restricted sites it may need a much larger crane, parked in the road (which can mean traffic management costs) to position heavy items, like roof trusses.

Difficult Construction This can mean more hand work or dealing with building a wall on a boundary with limited access, and having to support foundations of neighbouring buildings.

Parking Fees Sound insignificant,  but if its going to cost the tradies $5/day each when they normally park for free so they are going to want be charging that to your job.


See Blocks for more information on buying land


Can You Build On The Boundary?

I have previously talked about Setbacks but with certain limitations it is possible to build on the boundary.Generally  rules about building on a boundary apply to all buildings constructed on or within 150mm of a side boundary.

Typical Rules

Walls of a building including carports can be constructed to the side or rear boundary of a block provided:

  • The maximum length of wall on a shared allotment boundary, with an adjoining property, must not exceed 10m plus 25% of the remaining length of the shared boundary.
  • The maximum average height of a wall or carport on or within 150mm to a side or rear boundary must not exceed 3.0m and the maximum height must not exceed 3.6m.

NB If the neighbouring block has a wall on the boundary that exceeds these dimensions then your wall  can be constructed to the same height and width of the wall it will abuts.

As rules vary for different council areas check your councils website so you are sure of what rules apply to your block.

For more information about where you can build on your block see see Building Envelope.