As the planning permit documentation comes together, our thoughts turned to how best to share the sustainable design features with the Council personnel who will review the paperwork. Not really knowing how to do this, it was time to seek assistance. Out went a flurry of emails to anyone we thought might be able to help. As in the past, our contacts came through. We collected a variety of suggestions for how to do a sustainability assessment.
Sustainability assessment ideas from Green Building Council of Australia.
An email lobbed into the Green Building Council of Australia produced a very generous response with several suggestions.
For general guidelines on how to build according to sustainable design principles, the Australian Government has set up the Your Home website. This site is choc-o-block with ideas about how to minimise the environmental impact of a house design. You can find out how to use passive design to reduce heating/cooling needs. There are lists of construction materials with advantages and disadvantages. The website writers cover how to reduce resource requirements such as electricity and water.
The Australian Building Sustainability Association was recommended as a source of accredited assessors. Their expertise focuses on energy efficiency, building thermal performance and low carbon building materials.
This approach would provide a rating on how well our energy-related design features such as passive heating and high performance insulation would perform.
In a similar vein, the Nationwide House Energy Rating Scheme (NaTHERS) produces a star rating for a home. It’s a bit like the stickers you find on the side of electrical appliances. How much energy does the appliance use in the year? For a home, it’s about giving a rating out of 10 for energy efficiency, based on the design features. Making good design choices can reduce the energy demand for heating and cooling while still keeping the residents comfortable.
Wouldn’t it be informative to walk up to a house that is for sale and checking out the NaTHERS sticker on the back wall? Imagine the conversations around how much a low star rating would affect the selling price because the home’s running costs would be expensive.
These were excellent suggestions and a great place to start.
With the focus on energy efficiency, there wasn’t a place to get credit for other ideas in our designs. What is it worth to de-construct the existing house and reuse suitable materials in the new houses? Should having an indigenous landscaping plan add to our sustainability credentials? Would reviewers look favourably on the idea of using gravity-fed rainwater supplies for the toilet cisterns?
We felt we needed something a bit broader to run over our plans.
Using BESS for sustainability assessment.
While mulling over these ideas, we received a phone call from a contact at Maroondah Council on just this topic. That’s when we were introduced to BESS – Built Environment Sustainability Scorecard.
This appears to what we are looking for. BESS covers a broad range of sustainability ideas that can be included in a housing design. How is the project managed from a sustainability point of view? What will the indoor living quality be like in terms of low VOC paints, external views and sound proofing? What are the sustainable transport options for the residents (eg electric vehicle charging facilities, public transport)? Does the garden include space for growing fruits and vegetables?
Information from all parts of the design are fed into the model and compared with best practice options. The software then gives an overall rating of the design, based on its performance in all the sub-categories.
Councils are encouraging permit applicants to use BESS to generate a sustainability assessment. It means they have a recognised, easy to use format for their review process.
Yarra Council has made this a requirement for any Planning Permit applications that have multiple dwellings on a site. Their website provides assistance in how to prepare what they call a Sustainable Design Assessment. The good news is that in their experience, the Assessment documents can usually be prepared by the applicants without specialist assistance.
Our next step is to learn a lot more about BESS. What can the sustainability assessment do for us in terms of demonstrating our green home credentials?