WST-2 Construction Waste Reduction
Aim
To encourage and recognise a reduction in the amount of waste through building design and as generated
onsite during construction and/or major refurbishment.
Credit Criteria
Up to three points are available for this credit where it can be demonstrated that the waste generated from
construction activities has been reduced and diverted from landfill1. Points can be achieved via approach A
and approach B:
Approach A: Reduced Construction Waste
(1)
Where 15 – 20 kg is sent to landfill/cleanfill2 per m2 of gross floor area for the whole
construction/refurbishment project, OR
0.5point
(2)
Where 10 – 14.99 kg is sent to landfill/cleanfill per m2 of gross floor area for the whole
construction/refurbishment project, OR
1.0points
(3)
Where less than 10 kg is sent to landfill/cleanfill per m2 of gross floor area for the
whole construction/refurbishment project, OR
1.5 points
(4)
This credit is deemed Not Applicable for dwellings that have been in existence for
more than two years (from the date of assessment) and have not undergone major
refurbishment within the past two years (from the date of assessment).
N/A
Approach B: Increased Waste Diversion
(1)
Where 50 – 59% of total waste is reused and/or recycled and/or recovered for the
whole construction/refurbishment project, OR
0.5point
(2)
Where 60%-69% of total waste is reused and/or recycled and/or recovered for the
whole construction/refurbishment project, OR
1.0 points
(3)
Where 70% or more of total waste is reused and/or recycled and/or recovered for the
whole construction/refurbishment project, OR
1.5 points
(4)
This credit is deemed Not Applicable for dwellings that have been in existence for
more than two years (from the date of assessment) and have not undergone major
refurbishment within the past two years (from the date of assessment).
N/A
1
2
Landfill is defined as any earth filling activity other than cleanfill..
Cleanfill is defined as that contained in the MfE “A Guide to the Management of Cleanfills Jan 2002”
Assessment
This Credit is only applicable to dwellings built within the previous two years (from the date of assessment)
and existing dwellings that have undergone major refurbishment within the last two years (from the date of
assessment).
For a Design Rating, this credit can only be achieved if a Site Waste Management Plan (SWMP) is in place (as
per WST-1) and a specific target is stated for the construction of the project. The Assessor is to determine, by
reviewing the information supplied, if the stated target is realistic for the project.
For a Built Rating completed waste material reused and/or recycled and/or recovered (RRR) records must be
provided for the whole of the site which demonstrate compliance with Approach A and B. All figures must be
calculated byweight (kgs or tonnes)..
For the purposes of this credit, land clearing and hazardous materials should not contribute to the total
amount of waste produced for the project under Option A or B (provided any hazardous waste is disposed of
correctly in accordance with the relevant legislation and local authority requirements and evidence of this can
be produced). For clarity, demolition waste of existing residential building(s) needs to be included.
A waste contractor may be used to separate and process recyclable materials off-site.
Bulk Recycling
If a sub-contractor is engaged to carry out the RRR function on the project’s behalf and does it on a
‘bulk’ basis, not on a project basis, the credit can be claimed if the sub-contractor can provide signed
and auditable evidence of achieving the reduced waste and or increased diversion targets under
Approach A and B on a monthly basis.
Similarly, manufacturers’ take-back schemes can also be used for this Credit. Where this is the case, records
must be produced to demonstrate that materials are re-used/recycled as appropriate and as a minimum, wet
and dry materials must be separated on site.
Where the dwelling being certified is located in a larger building, and therefore shares a common building and
common site with other dwellings an overall site approach may be taken for this credit and the results applied
to each dwelling within the building.
Audit Documentation
Design Rating
SWMP clearly stating the waste target OR where a SWMP has not yet been written an extract from either the
building contract or tender documentation clearly stating the waste target.
Built Rating
For all projects
Monthly waste and RRR reports for the entire duration of construction works, are to be signed and witnessed
at each stage of reporting by senior Company representatives of the Waste and RRR Contractor.
These reports will clearly state the reported level of RRR that has actually taken place.
For Approach A: Reduced Construction Waste
Photo or copy of the completed waste records based on monthly reports for the whole of site which display the
weight of waste sent to landfill/cleanfill measured in units of kg/m 2.
For Approach B: Increased Waste Diversion
Photo or copy of the completed monthly waste and RRR records for the whole of the site which display the
percentage of total waste reused, recycled or recovered sent for measured in units of kg.
If the waste has been sorted off site (i.e. mixed waste has been collected from site) then proof of the RRR
performance must be provided. Receipts/dockets from the recycling providers would be acceptable
Where the Credit is deemed Not Applicable to the dwelling:
Signed pro forma from the owner to confirm that the dwelling has not been built within the last two years and
has not undergone a major refurbishment.
Background
The construction and demolition (C&D) industry is one of the largest waste producing industries in New
Zealand. C&D waste may represent up to 50% of all waste generated in New Zealand, 20% of all waste going to
landfill and 80% of all waste going to cleanfill1.
Disposing of these materials to landfill not only means that they are not being recovered for further use but
also that they then contribute to adverse environmental effects such as leaching of chemicals into soil and
waterways as well as creating emissions of methane as construction and demolition waste decomposes. Much
C&D waste can be reduced, reused and recovered, dramatically decreasing the amount thrown away 1. A 1997
study showed that by simply sorting construction industry bin waste, it was feasible to reduce the amount by
50-55%, using off the shelf equipment and technology. This is still likely to be the case 2.
REBRI is a New Zealand initiative specifically developed to address construction related waste. Its purpose is to
promote, advocate, and assist resource efficiency measures in the building and related industries. REBRI grew
from a collaborative effort in 1995 between the Auckland Regional Council, BRANZ and the Auckland City
Council, with some funding by the Ministry for the Environment. It now is an extensive resource for the
building industry, with research, demonstration projects, sorting trials, guidelines, information papers,
checklists, market development and product stewardship resources all available as free downloads3.
The purpose of this Credit is to encourage contractors to take part in effective waste and RRR management
practices. These efforts will play a significant role in the construction industries reduction of waste as a whole.
References and Further Information
1.
Heritage Building Preservation – The Ultimate in Green Building?
http://researcharchive.lincoln.ac.nz/dspace/bitstream/10182/3218/3/McDonagh_Heritage_buildings.
pdf
2.
REBRI Guidelines
http://www.branz.co.nz/REBRI
3.
Onsite Waste Minimisation
http://www.smarterhomes.org.nz/construction/construction-site-practice/on-site-wasteminimisation/
4.
Target Sustainability Waste Reduction Case Studies for House Builders
http://www.targetsustainability.co.nz/CaseStudies/housebuilders.asp
5.
Minimising Waste
http://www.level.org.nz/material-use/minimising-waste/
6.
Zero Waste Initiative
www.zerowaste.co.nz