What we do

The Environmental Solutions Research Centre (ESRC) was established in 2019, led by Associate Professor Terri-Ann Berry. The centre is highly collaborative and fosters transdisciplinary research initiatives that push the boundaries of current disciplinary silos. ESRC involves chemists, biologists, engineers, epidemiologists, geographers, and building and construction experts. This involves collaboration with industry leaders from various fields such as waste management and minimisation, air quality, wastewater treatment, and civil engineering, who work on complex and multigenerational challenges such as asbestos-contaminated soil, indoor air quality, and plastic reduction in construction.

Current research

ESRC currently working on the following projects.

Sustainable management of plastic waste on construction sites in New Zealand: a co-operative solution to improve on the cradle to grave approach.

Auditing the plastic waste generated from six active new-build construction sites of different types (three commercial and three residential) and sizes (three small, two small to medium, and one medium) over the whole construction period to identify the main causes of plastic waste generation, including packaging materials, componentry, and building protectors.

The team is working with the plastics industry, building product suppliers and manufacturers, and the waste management sector to identify alternative options for plastic use, to encourage reduced reliance on plastic packaged construction materials, and to identify issues and opportunities around developing markets for used plastic, with the aim of diverting plastic waste from landfill.  They are also working with the construction sector to develop, communicate and implement practical, on-site solutions to reduce plastic use and appropriately manage plastic waste, i.e. through reuse or recycling.

Building site plastic waste sorted in to piles in a carpark
Plastic waste audit.

Determine the feasibility of a circular economy for Scaffolding, Access, and Rigging NZ (SARNZ) plastic waste

Working with the plastics industry, key suppliers and manufacturers to SARNZ members, and the waste management sector to identify opportunities for change. This includes identifying unnecessary and problematic plastics to eliminate them and identifying opportunities for creating circularity through reuse and recycling. The overall aim is to diversion plastic waste from landfills. The team will also work with SARNZ to develop, communicate and implement practical, on-site solutions to reduce plastic waste, including the production and delivery of educational resources to maximise uptake.

Closing the Loop on PVC and HDPE construction and demolition waste

In partnership with Aliaxis/Marley NZ, this involves the investment in four new sorting, washing, and shredding plants intended to close the missing link in completing the circular loop for recycling products made from material recycling codes 2 (HDPE) and 3 (PVC) materials sourced from construction and demolition, commercial and industrial sources.

Pipe products manufactured from suitable materials have a service life of between 50 to 100 years. Furthermore, following their end of life, they can be recycled once again. As part of creating this loop, this project will kickstart putting in place a collection service for suitable PVC and HDPE waste. This will aid in the recovery of end-of-life uPVC and PE piping systems, waste generated at the time of installation, as well as any other suitable PVC or HDPE products, such products can include:- IBC’s, drums, HDPE bottles, gutter, plastic formwork, cladding, and window surrounds.

To maximise the contribution from the construction and demolition industry, it is essential to develop effective on-site waste management and diversion procedures. This will allow the collection and recycling of high-quality, uncontaminated plastic waste that will optimise the potential of the
proposed recycling infrastructure towards building a circular economy in the NZ Construction Sector. Partnering with Unitec’s Environmental Solutions Research Centre (ESRC) and Waste Management New Zealand (WMNZ) will allow Marley to amplify the message of recycling throughout the industry, as well as work together on practical solutions to minimise plastic waste going to landfills in the Construction and Demolition industry. 

Using low-cost sensors to determine the effects of home ventilation technologies on a variety of Internal Air Quality (IAQ) markers

Investigating the variability of various IAQ parameters in houses pre- and post-installation of a ventilation system in the Auckland and Hamilton regions. We aim to provide evidence to support the notion that effective use of ventilation technologies can reduce moisture loads and improve IAQ, also to then relate this improved air quality to a healthier environment.

The long-term goal of the project team’s wider IAQ research programme, of which this project will be part, is to identify viable solutions to help vulnerable communities currently living and socialising in poor IAQ environments.

Internal air quality sensor that looks like a small table lamp stands on a coffee table in a lounge
Low-cost internal air quality (IAQ) sensor.

Remediation of asbestos-contaminated soil: an alternative to landfill disposal

Asbestos-contaminated demolition waste and soil are placing an increasing burden on hazardous landfills.  In addition, under the exclusion of water and air, the waste will remain harmful indefinitely.  Even soil and materials with a very low asbestos content (<1% by weight) can generate hazardous levels of exposure when disturbed.  Currently, no long-term unified approach addresses either the increasing waste volumes or the legacy of multiple sites of contaminated land.

By determining the effect of various micro-organisms on the degradation of asbestos fibers in-situ, this project will investigate the potential for bioremediation of asbestos-contaminated soil as an alternative to hazardous landfill disposal.

Asbestos-containing material.

Research publications

Encouraging circular waste economies for the New Zealand construction industry: opportunities and barriers

Link to article in Frontiers.

Authors: Low, J.K., Wallis, S.L., Hernandez, G., Cerqueira, I.S., Steinhorn, G. & Berry, T-A.
Journal: Frontiers in Sustainable Cities.
Date: 2020.
As our global population increases, the resulting waste mountain continues to rise. It has been identified that the Construction Industry contributes to a large proportion of the waste to landfill (and cleanfill) sites. Whilst there has been a multitude of commercial ventures and research-based activities targeted to challenge waste volumes, the ambitions of a truly circular economy for this industry remain far from realised. This article will discuss industry examples of waste minimisation initiatives that have been implemented successfully to support a less linear approach and encourage sustainable waste management for industrialised nations. We also identify the limitations of this decentralised approach to resource management and suggest how the creation of resource markets, on both national and international scales, could connect the waste management loop for a vastly improved environmental outcome.

Disposal or Treatment: Future considerations for solid waste from the construction and demolition industry

Link to article in witpress.

Authors: Wallis, S.L., Lemckert, C., Hardy, R. & Berry, T-A.
Journal: WIT Transactions on Ecology and the Environment.
Date: 2020.
Each year more than 2 billion tonnes of municipal solid waste are produced globally. The greatest worldwide users of resources in terms of raw materials and energy are from the construction sector. Construction, demolition, and excavation waste accounts for a large share of municipal waste and the majority of this waste goes to landfill. Worldwide, the proportion of landfilled construction, demolition, and excavation waste compared with the total amount of waste is variable from 13% to 60%+. Many developed countries are now facing issues with land capacity and are less flexible in their approach to solid waste treatment.
New Zealand is a relatively young and geographically isolated country with enough available land to be able to trial new options for waste treatment and currently has seven different types of landfills, including construction and demolition and cleanfill options. Biodegradable substances can be treated via processes such as composting and anaerobic digestion, but substances that are either hazardous or inorganic in the structure are generally considered to be untreatable and therefore reduce practical options for landfill or incineration. As any potential treatment in landfills is limited by less than optimal environmental conditions, their primary purpose is simply to hold and isolate the waste. Incineration has high energy costs and does not support a low-carbon economy.
As neither of these options presents an ideal long-term solution to solve this waste problem, this paper will consider sustainable options for the disposal and treatment of construction, demolition, and excavation waste with a focus on hazardous materials. It will consider New Zealand as a potential case study location for trialing solid waste treatment options whilst discussing waste issues in other countries such as Australia, the United Kingdom, and the United States of America. It will also identify barriers that may prevent the treatment of solid waste including considerations for protecting public health and safety.

Asbestos and other hazardous fibrous minerals: Potential exposure pathways and associated health risks

Link to article in MDPI.

Authors: Berry, T-A., Belluso, E., Vigliaturo, R., Giere, R., Emmett, E.A., Testa, J.R., Steinhorn, G. & Wallis, S.L.
Journal: International Journal of Environmental Research and Public Health.
Date: 2022.
There are six elongate mineral particles (EMPs) corresponding to specific dimensional and morphological criteria, known as asbestos. Responsible for health issues including asbestosis, and malignant mesothelioma, asbestos has been well researched. Despite this, significant exposure continues to occur throughout the world, potentially affecting 125 million people in the workplace and causing thousands of deaths annually from exposure in homes. However, there are other EMPS, such as fibrous/asbestiform erionite, that are classified as carcinogens and have been linked to cancers in areas where it has been incorporated into local building materials or released into the environment through earthmoving activities. Erionite is a more potent carcinogen than asbestos but as it is seldom used for commercial purposes, exposure pathways have been less well studied. Despite the apparent structural and chemical similarities between asbestos and fibrous erionite, their health risks and exposure pathways are quite different.
This article examines the hazards presented by EMPs with a particular focus on fibrous erionite. It includes a discussion of the global locations of erionite and similar hazardous minerals, a comparison of the multiple exposure pathways for asbestos and fibrous erionite, a brief discussion of the confusing nomenclature associated with EMPs, and considerations of increasing global mesothelioma cases.

Plastic Minimisation in Construction: A pilot study identifying and quantifying the composition of C&D plastic in construction waste

Authors: Kestle, L., Hernandez, G., Berry, T-A., Low, J.L. & Wallis, S.L.
Journal: Australasian Universities Building Education Association (AUBEA) Annual Conference.
Date: 2021.
Construction and demolition (C&D) waste contribute at least 10,000 tonnes of plastic to landfills in Auckland annually. The growing use of plastic in the packaging of building materials, the use of polystyrene, and products such as building wrap are contributing to this landfill stream. Most construction waste is not sorted on construction sites, with C&D waste often being co-mingled. This funded research is an exploratory study being undertaken as a pilot project over 12-18 months by academics with three industry partners (a commercial construction company (Naylor Love), a leading building materials’ supplier (Mitre 10), and a large recycling company (Green Gorilla), to undertake a comprehensive waste audit analysis of plastic waste, and workplace incentivisation for source separation of waste. The research grant was awarded to Unitec Institute of Technology by the Auckland City Council in December 2019. To date, the research team (principal investigator assisted by another senior researcher and two research assistants, a plastics technician, and an industrial chemist), has audited and recently analysed the first of two rounds of the plastics’ recycling bags that were located at three of the construction company’s project sites. Mitre 10 and Green Gorilla are providing the research project with statistical data related to the products being supplied and recycled to and from the three project sites. The main aim of the collaborative pilot research project was to investigate how to identify and quantify the composition of C&D plastic in construction waste going to landfill. As the pilot research project concludes later in 2021, the results to date are preliminary, yet positive. The findings demonstrate the value-added results of this collaborative academic and industry partnership, and the commitment to making a real difference that Naylor Love, and Mitre10, in particular, have achieved, for minimising plastic and plastic waste on their projects, and influencing clients customers and other players in the construction industry.

Thermal performance and indoor air quality in new, medium-density houses – Auckland, New Zealand

Authors: Birchmore, R.C., Berry, T-A., Wallis, S.L., Tsai, S. & Hernandez, G.
Journal: International Journal of Building Pathology and Adaptation.
Date: 2022.
Purpose – New Zealand’s historical housing stock comprises largely single-story detached houses, characterised by poor winter comfort with high air infiltration. Challenges with affordability and land use are shifting New Zealand’s housing stock towards double-story, conjoined medium-density housing (MDH). Reduced external surfaces in this typology should reduce winter heat loss and infiltration, improving winter comfort and health. New concerns arise, however, regarding summertime overheating and poor indoor air quality.
Design/methodology/approach – Afield study was undertaken where temperature, humidity, airtightness, particulate matter (PM), and total volatile organic compounds (TVOC) were measured in two unoccupied, newly built double-story, conjoined houses, for several weeks over summer.
Findings – The reduced surface area of this typology did not reduce infiltration and demonstrated significant periods of overheating. Internal PM concentrations generally exceeded outdoor concentrations but did not exceed the annual average outdoor PM10 guidelines of 20 mg m-3. Infiltration factors (Finf) were closer to more traditional houses. TVOC readings varied widely, but frequently exceeded international guidelines.
Research limitations/implications – The small sample limits the applications of conclusions more widely. Recommendations to investigate a wider sample in different locations with more detailed VOC analysis over all seasons are made.
Practical implications – Improvements to internal environments cannot be guaranteed by housing typology changes alone and must still involve thoughtful environmental design.
Social implications – Housing typology changes may not improve internal living environments.
Originality/value – A move to the new MDH typology may not achieve expectations of airtightness and thermal improvement. New challenges arise from significant overheating and high TVOC levels, which may lead to new negative health effects.

Quantifying and managing plastic waste generated from building construction in Auckland, New Zealand

Link to article in SAGA journals.

Authors: Hernandez, G., Low, J.L., Nand, A., Bu, A., Wallis, S.L., Kestle, L. & Berry, T-A.
Journal: Waste Management & Research.
Date: 2022.
Each year, construction and demolition (C&D) waste contribute at least 25,000 tonnes to the total amount of plastic landfilled in Auckland, New Zealand. The growing use of plastic in the packaging of building materials, the use of polystyrene and products, such as building wrap, are contributing to this. Unlike countries such as the UK, most construction waste in New Zealand is not sorted on-site, and C&D waste is often co-mingled; therefore, minimal analysis on the recoverability of plastics has been attempted. This study identified and quantified the plastic waste stream produced from four construction sites, generated from various stages of construction in Auckland, New Zealand. Plastic waste was taken over three construction stages including demolition, exterior and weatherproofing, and services and cladding, amounting to 112 kg (or 11.2 m3). The main types of plastic analysed were polyethylene, contributing 77% (by mass), and polyvinyl chloride, representing 31% (by mass). The main reason for the generation of plastic waste across the four sites was highly variable and dependent on the construction stage. However, it was apparent that plastic packaging of materials was not the single area of concern, and plastic building componentry and protection materials should also be investigated for their contribution. This study supports the requirement for improved understanding and awareness of the composition and fate of plastic C&D waste. Long-term benefits to the construction industry are from raising awareness of the potential to make profits from valuable waste products and to improve environmental performance and reputation, for a competitive advantage in New Zealand.

Contact the Environmental Solutions Research Centre

Email: esrc@unitec.ac.nz
Physical address: We are located at Unitec, Te Whare Wānanga o Wairaka, 139 Carrington Road, Mount Albert, Auckland New Zealand.