Preliminary Site Plans
Points To Note
When locating a house on a lot consideration should be given to;
- Location of services to be connected (water, power, sewerage)
- Orientation (summer/winter aspects)
- Access (crossovers, gates)
- Check title for any easements/restrictions
- A diagram of survey (re-peg of lot including AHD levels)
This ensures that the construction is completed on the correct lot with correct setbacks.
Setbacks is the name given to the distance between the lot boundary and the external face of the house. This distance is measured from the lot boundary to the external face of the house, eg brickwork.
As a guide, for a single storey house on a level block, the following is provided:
Front & Rear Setbacks: Please contact the Shire of Waroona Planning Officer.
Side Setback: For walls less than 9000mm in length, max 3000mm in height containing only minor opening to non-habitable rooms. 1000mm Min. setback. For walls greater than 9000mm in length, max 3000mm in height. 1500mm Min. setback
Nil/Zero Setback: Where are zero side setback is sought enquiries should be made to the Council’s Building Department.
Where a lesser setback is sought to front or rear boundaries, enquiries should be made to the Council’s Planning Department.
For Rural or Special Rural Zoned Lots, Commercial, or Group Development enquiries should be made to the Council's Planning Department.
Finished Floor Levels (FFL)
This level is confirmed by the Council after the initial assessment is made of the building application. Factors which influence the FFL are:
- The proposed residence is located in a flood fringe area.
- There is an indication of a high ground water table.
- Engineering requirements, eg height of sand pad, footing depth, presence of reactive soils such as clay, presence of rock, etc.
- The leach drains may be required to be partially or fully inverted, this may influence the FFL as falls are required for the operation of the septic system without a pump being installed.
- The perceived impact on adjoining properties.
Because of the range of conditions within the Shire, it is not possible to apply a single policy. Enquiries should be made with the Council when planning to build as there may be specific requirements for your lot regarding FFL's.
Reduced levels are those levels taken of the lot in relation to a datum point installed (typically) in line with a side boundary on the road denoted by a nail and plate, or top of kerb. The datum point, also referred to as a temporary bench mark is given a value eg. 10,000 and all levels taken of the lot are "reduced" back to the datum. This can be done by a person who is competent at using a level. When plans are submitted for a Building License the Building Surveyor can check these levels and if not satisfied with the accuracy can ask for a diagram of survey to be submitted prepared by a Licensed Land Surveyor.
It is normal practice in the building industry for levels to be shown on the site plan by contour lines at half metre intervals and spot levels at all corners along the boundary, and wherever it is thought necessary. Should fill be required then knowing the required FFL and deducting the thickness of the floor slab, an accurate estimation can be made as to the quantity required. Should a "cut and fill" situation be the case, an estimate can be made of the amount of work to be done.
If a "brick build up" is used, accurate levels are necessary in order to determine quantities of material needed.
Other trades benefit as well, such as the plumber who installs the septic system. When any earth works are undertaken accurate levels are a must.
The benefits of a diagram of survey and accurate levels are:
- Having a formal document of your lot that can be used to estimate quantities.
- The lot is identifiable on site by survey pegs.
- Dividing fences can be installed on the legal boundary.
- Existing dividing fences can be checked for position.
- Exact levels of the natural ground profile enables the desired finished levels to be achieved. eg retaining walls, terracing, falls for brick-paving, concrete, etc.
- In the event of a dispute, the document can be referred to by both parties.
- Engineer's Site Detail & Report.
- With new dwellings it is normal for the Council to require that the footing detail be endorsed by a practicing Structural Engineer.
The reason for this is that it requires specialised knowledge to specify the size and type of footing for the type of structure proposed. Site conditions vary, with many factors influencing the Engineer’s choice of footing detail. Should a problem arise and the footings thought to be at fault, the Certifying Engineer can be called upon for remedial action. The Council does not accept liability in the event of a structural failure. In order to be satisfied that structural parts of the dwelling perform, reliability/confidence is placed on the Structural Engineer for certifying plans and checking detail where the Building Surveyor is not satisfied that the design conforms to accepted building practice or complies to an Australian Standard.
Where construction is proposed on lots that are deemed to have difficult conditions, an Engineer’s site report will need to be obtained. This report is compiled by the Engineer and is a statement of the results of a formal investigation of the site. This assessment is used when specifying footing detail, and if the need arises, site drainage requirements may be specified.
The site is classified in accordance with an Australian Standard, after visual inspection of the surface material and soil samples are taken from bore holes at a depth of up to 1500mm. Should there be any other feature on site which would effect the structural integrity of the dwelling, then this would be noted so as to allow consideration when the dwelling is designed.
An Engineer's certification and/or detail, will be required in the following circumstances:
- Plans submitted for approval lack structural detail
- Beam sizes and connection detail are inadequate
- All retaining wall in excess of 650mm in height
- Brick build-ups in excess of 650mm in height
- Brick wall in excess on 3000mm in height
- Where site drainage is required
- Alternate forms of construction (eg rammed earth)
- Two storey constuction
- Suspended slabs.
Should the Building Surveyor not be satisfied with the work completed on site, then an Engineer's certification/report may be required to be submitted to Council.
Plans & Specifications
It is recommended that plans and specifications be drawn by a professional.
Until your house is completed, the plans will be referred to constantly, and relied upon for accuracy during construction. Remember, if you cannot build the house on paper, you will not be able to build it on site.
A "set" of house plans consists of:
- Site plan
- Floor plan
- All elevations (Note – the above are known as architectural drawings)
- Sectional views
- Special/custom detail
- See attached requirements.
Plans are required to be "formal" drawings to scale, anyone can draw house plans, but remember, it is a specialised field which requires experience in order that the drawings can be relied upon to be referenced when queries arise. Two copies or "sets" are required to be submitted for approval. They are assessed by the Building Surveyor for compliance to the Building Code of Australia, Local-laws, Residential Planning Code, and that the detail is structurally sufficient for the design. Once satisfied that a house can be constructed using the submitted plans, they are individually stamped and the building license number recorded. One copy is returned to the applicant with the building license and form part of the documents of approval. Should any questions arise at to what was approved, the plans are referred to and if necessary can be used in court.
Conditions Of Approval
The Building Surveyor will impose conditions and these should be read carefully when the Building License is issued. If you have any queries or concerns, discuss these immediately with the Building Surveyor. If dissatisfied with any condition, you must lodge an appeal with the Minister for Local Government.
Specifications are all the other items not listed on your plans, necessary to complete the house.
Details such as colours and surfaces to specific finished, fittings, fixtures, particulars or manufacturer's model numbers, custom items, and items that are specifically chosen. It is recommended that a detailed specification be used with a set of plans.
Before a building approval is given, the Council must be satisfied that the new residence is serviced by an approved effluent disposal system.
If your lot is serviced by a mains reticulated sewer system then the site plan must be approved by the Water Corporation. This is done by submitting the plans to be approved by the Council to the Water Corporation first. The Water Corporation will stamp the plans thereby indicating that the proposed residence, when constructed, can be connected to the reticulation sewer system. Applications without Water Corporation approval will not be accepted.
Note - It is recommended that when a preliminary site plan has been drawn the Water Corporation be consulted so as to ensure that the proposed dwelling does not encroach on any Water Corporation easement. Doing this at this stage will avoid the need to relocate the proposed residence after the final plans have been produced.
Main Reticulated Sewerage
If your lot is serviced by the reticulated sewerage system, then your new house will need to be connected to it. A licensed plumber and the Water Corporation should be contacted for further information.
If your lot is not serviced by the reticulated sewerage system and you choose to use a septic system then a Septic Tank Application will need to be submitted to the Council with your building application for approval.
It is recommended that you seek assistance with this application from a licensed plumber that will be installing the system as specific details are required.
When this application is received the Environmental Health Officer will conduct a site inspection and, if necessary, impose conditions that are required to be met.
Aerobic Treatment Unit (ATU)
This type of effluent disposal system is subject to approval and installation is by the manufacturer. In some new sub-divisions this is the only type of system which is permitted to be installed.
If you have any doubts regarding effluent disposal, enquiries should be directed to the Environmental Health Officer of the Shire.
You are required to nominate an accredited termite barrier with your building application. This is a requirement for the building licencse to be issued. The Building Application will not be processed if the termite barrier has not been received.
Once you have decided which barrier you are going to use you will need to nominate in writing the details of the barrier and the method of installation. This can be done in the specifications or in a separate letter submitted to the Council.
There are two main types of termite barriers, chemical barriers and physical barriers. The choice is yours to make provided it is accredited to the Building Code of Australia. If there is any doubt, contact the Council for advice.
Deleting The Termite Barrier
Should the house be constructed of termite resistant materials then a barrier is not mandatory. eg concrete slab, brick construction, steel roof framing.
This would satisfy the Building Code of Australia, but recent experience has shown that termites still enter the dwelling and attack the contents of the house where there is any carbonaceous material such as:
- Wooden fittings
- Skirting boards
It is recommended that an accredited termite barrier be installed and maintained regardless of the type of construction used.
The three main types of insurance that should be considered are:
- Worker's Compensation
- Public Liability
- Theft & Damage
Although insurance is an additional cost, it is highly recommended that the necessary cover be obtained as any claim against the owner/builder has the potential to make restitution that can stop the project from being completed.
Enquiries should be made to an Insurance Broker as to the most applicable cover to your circumstances.
THE BUILDING COMMISSION CAN BE CONTACTED BY PHONING 1300 48 90 99
The Building Commission is responsible for administering the BUILDERS' REGISTRATION ACT.
All construction with a value in excess of $20,000 is subject to the provisions of the Act. A building license can only be issued to a Registered Builder, or to a property owner who has obtained an Owner/Builder's license directly from the Builders' Registration Board.
In this regard, an Owner/Builder must complete an application and lodge it directly with the Building Commission. When approved the Council is automatically notified. A building license will not be released until this advice is received. An application fee of
- $148.75 for an application for a detached dwelling including a garage, shed or other building associated with a dwelling; or
- $455.50 for an application for a small commercial building.
is paid directly to the Building Commission.
Identifying Your Property
During construction you are required to display a sign denoting the lot number, building license number and the name of the Owner/Builder.
It is recommended that letter be a minimum of 50mm in height and made from a reflective material.
The Quantity Surveyor
The Quantity Surveyor is a specialist who is able to produce a bill or orderable quantities from interpreting your plans. This list will be invaluable, as it not only provides an accurate "shopping list", but also enable concise pricing of all materials needed to build your house.
These notes are prepared to give a basic overview of the initial steps involved.
From this point, it is highly recommended that further enquiries be made from relevant authorities and from source material such as self help books.
Do not overlook the possibility of having your project supervised at crucial stages by an industry professional such as a Registered Builder, Structural Engineer or Architect. It may be prudent insurance for a successful completion.
REMEMBER – "If you cannot build on paper, you cannot build on site."