The design is the single most important element in creating a building, whether it is a new home or a renovation. Building design is a complex task that is best entrusted to a professional. It is not simply a matter of ‘drawing a set of plans’. Every building project is unique and has its own complexities. It is the task of the designer to understand these complexities and maximise the potential of the site.
Those sites with steeply sloping land that are prone to landslip are covered by an Erosion Management Overlay (EMO). In most cases a planning permit will be required for all of these applications and will require a report from a qualified Geotechnical consultant.
Recommendations often include minimising earthworks, minimal tree and vegetation removal, deepened piers for foundations and any retaining walls to be designed by a Structural Engineer. Any existing un-retained cuts and fill may also be affected. Good drainage is also an important consideration. Ongoing maintenance is usually also suggested. Some properties that fall in a High landslip may be unsuitable for development.
The majority of the Shire of Yarra Ranges and Cardinia Shire are in the highest fire risk category, are more likely to be exposed to the threat of bushfire and therefore are currently assessed to be in a Bushfire Management Overlay (BMO).
Where the BMO applies to a property, a planning permit will be required to construct a new home, and also an addition to a residence, where the area of the addition is more than 50% of the existing building. Large sheds can also be a trigger a compliance with a BMO. A Bushfire Management Statement must be prepared to accompany the Town Planning application to determine that the requirements of the BMO have been met. It will contain a Bushfire Site Assessment prepared to calculate defendable space and minimum construction requirements. The report will also demonstrate how the application meets the relevant objectives, standards and guidelines.
Defendable space has an inner zone and an outer zone, which will be dependent on the site slope and the local vegetation. Water supply and CFA access to the property are also assessed.
The approved BMO will also include a Bushfire Assessment Level (BAL) rating. The lowest being BAL 12.5 and the highest being BAL FZ. This rating is a requirement for a building permit and will give us an idea of the type of materials that will be suitable to use. Ratings up to BAL 29 are not that stringent, and some timbers that are bushfire resistant can be used. Ratings of BAL 40 and BAL FZ require quite a bit more thought and will considerably increase your building costs.
Please do not hesitate to call, to discuss any of your design questions! 03 9754 7464
The Yarra Ranges Council and Cardinia Shire Council have extensive controls for the removal and lopping of trees and native vegetation and will most likely require a Planning Permit. Ornamental or European trees are also included if they are taller than 4m.
Sometimes it is not possible to avoid tree removal; in this case an Arborist will need to give a written report on the health of the tree and the significance of the tree in regards to the landscape and the ecology of the area. The report will also examine the impact of the proposal on the health of the tree as well if it is to be retained. The Council can request replanting and other environmental improvements to offset any removals.
Not all trees and native vegetation removal require a planning permit. For those properties in a Bushfire Management Overlay (BMO) trees within 10m of your home and undergrowth can be removed under the 10/30 rule as a safety measure. Trees close to your boundary fence are also covered by this rule.
All new homes, renovations and additions must now achieve a 6 star Energy Rating. This can be achieved mostly with increased insulation to the roof, walls and suspended floors. Improved glazing (double glazed window frames), good orientation and appropriate shading will possibly also be required.
Where the size of the addition will increase the existing home by more than 50% of its volume, the whole house will need to be brought up to 6 star standard.
North facing orientation to Living areas is highly beneficial. Locate non-habitable rooms to the west (i.e.: bathrooms, laundry and garage).
Maximise north facing windows and avoid high window to floor area ratio. Minimise west and south facing windows. Timber, UPVC or improved aluminium window frames provide higher star ratings than standard aluminium frames. Double-glazing is more effective than low-e or tinted finishes
Minimise external wall surfaces. Small houses rate higher more easily; bigger homes with high cathedral ceilings rate lower.
Provide self-sealing exhaust fans and dampers to chimneys or flues. Skylights generally don’t rate very well and are not suitable for high bushfire risk areas. External doors and windows will need to be fitted with draught/weather seals.