The project was submit for building approval in August 2011 and we got the green light on the 6th of October 2011. All in all it took longer time to submit for building approval. The most difficult issues that we had to deal with were government rules and regulations around fire construction for apartments and the use of a shared rainwater tank and greywater system. It's going to be a bit technical, but we'll try to explain the issues.
We will not easily forget the day when we were told that there was a major hiccup with the engineering of the apartments. That there were fire issues and that we would need to install sprinkler systems over all the windows in order to comply. Or we could choose not to use the loft space, not even for storage. The project came to a grinding halt. We had found ourselves another issue to get our teeth sunk into. I remember spending an afernoon in the university library studying the Building Code of Australia... I will try to explain the issue, but will not claim being an expert :-)
The Building Code of Australia (BCA) consists of two volumes. One of the volumes covers class 1 buildings which are most residential buildings. The other volume covers all other classes and includes multi dwellings (or apartments). The apartments which are part of our project need to adhere to this volume of the BCA. This includes fire construction.
Obviously the fire requirements are more strict for apartment buildings. You may not know who lives upstairs from you. If a fire breaks out in your neighbours apartment, you need enough time to escape from the building.
The requirements for type of construction for fire depend on the number of storeys. The definition of a storey is different under the BCA compared to the definition that applied for planning approval. Under the BCA, our apartment building was classed as 3-storey, because the loft was included, even though as per the plans it is only used for storage.
The BCA sets out the requirements for e.g. walls, roof, floors, and openings. The requirements are more strict if you have a building with more storeys and depend on the distance between the building and a potential fire source. A potential fire source is the lot boundary or another building. In our development, the apartment building is fairly close to the two townhouses; also part of the building is on the lot boundary.
How we resolved the issue:We engaged a fire engineer to prepare a report for the Town of Victoria Park. This report states how our apartment building is deemed to comply with the BCA. The fire engineer has done calculations and looked at whether our building is in line with the intention of the code. Below is a summary of the outcome:
- Walls: we changed from reverse brick veneer to double brick construction for the upstairs apartment. Double brick complied with the required fire rating; the fire rating of the reverse brick veneer product was unknown.
- Floor: we already had a suspended concrete slab between the two apartments to improve the performance of the upstairs apartment. We've ensured that this floor complies with the required fire rating
- Openings: the windows in the stairwell will be replaced with glass blocks. Glass blocks comply with the required fire rating. The fire engineer's calculations confirmed that the apartment's north facing windows and sliding doors complied. We asked the Town of Victoria Park for an exemption for the windows close to the lot boundary, however were asked to get calculations done for these windows also. Fortunately they all complied. There was no need to either remove them or install sprinklers above the windows...
For information on the issues around our proposed water solution, click here.
Building Approval Challenges
- Fire requirements under the Building Code of Australia. Our apartments are defined as a 3-storey building and therefore fall in the strictest class. We needed to engage a fire engineer to do calculations for most windows and write a report for the council stating that our proposal complies.
- Water... This may come as a surprise being located in one of the most water challenged parts of Australia, but implementing shared rainwater tanks and using grey water on common land are deemed to be high risk and need to comply with strict management and monitoring requirements.