Approaches to sustainable procurement - Environment Canterbury
River engineering quality and environmental management system manual
Environmental impact of building materials
River engineering quality and environmental management system manual
Some council departments have their own operational guiding principles. For example, the River Engineering Section uses a "quality and environmental management system manual". This manual defines that one of the criteria to be considered in supplier and contractor evaluation is "proven environmental awareness and compliance".
Environmental impact of building materials
The choice of building materials we select can have a dramatic effect on the environment. The client and building designers have a far greater ability to affect the environment than many of us realise. Materials can cause ecological damage in the following ways: -
- their extraction - eg. logging or mining practices. An example is the specification of timber - we have the ability to use either sustainably sourced timber or non - sustainably sourced timber.
- their production - the industrial production of certain materials is far more damaging than others due to the pollutants emitted. For example the production of PVC can result in the production of a number of toxic and carcinogenic pollutants.
- their embodied energy - this is the energy that goes into the production and transport of the material. For example in a typical house the simple choice of using steel framing as opposed to timber framing will increase the amount of energy embodied in the building materials by an amount equal to 3 years worth of day to day energy usage.
- their use - many materials give out polluting gases or leach polluting residues which can be poisonous to humans as well as the environment. For example solvent based paints and many man-made fabrics which give off during their lives VOC's (Volatile Organic Compounds) and Formaldehyde all of which are carcinogens. These are all contributory factors in the Sick Building Syndrome.
- their re-use / demolition - some materials used in buildings can be successfully dismantled and re-used others cannot be disposed of safely and stock piling is the only solution.
The following is a list containing many of the building elements that are likely to be incorporated into the Environment Canterbury building project. Each building element contains a brief description of the environmental issues at stake and a list of the best or worst environmental alternatives with respect to that material.
The list will provide a basis for the Quantity Surveyor to put cost implications against each material decision. The list will therefore also allow Environment Canterbury to make informed decisions on the environmental impact of their new buildings' materials.
Concrete
Concrete can be manufactured with a significant recycled content and so can be contributory in a zero waste policy.
- Best - concrete with recycled concrete aggregate.
- Best - concrete with high percentage of recycled industrial waste - eg. Duracem uses 75% blast furnace slag by Milburn New Zealand 348 8509. (Note slower to cure)
- Acceptable - concrete with greater than 5% of recycled industrial waste - eg. Self - compacting concrete or Micropoz concrete by Firth. Or a specialist mix by Milburn New Zealand.
- Refer to structural engineer for guidance on appropriateness of the various systems.
Timber framing
Timber should be sourced from sustainable sources such as plantations. Timber is a renewable resource and should be preferred to steel studwork.
- Best - Kiln Dried untreated certified NZ plantation timber.
- Next best - Kiln Dried untreated certified foreign plantation timber.
- Worst - timber from unknown sources
- Worst - steel stud framing
Timber treatment
Timber treatment is important to ensure the longevity of the building however the production of timber preservatives and the treatment of the timber itself is a polluting process. It also renders the timber a toxic waste on demolition or disposal. Therefore timber treatment should not be over specified and treatment with less environmental impact should be chosen over more polluting alternatives.
- Best - Boron - H1 only.
- Best - CAF (Copper - based chrome and arsenic free treatments.) H1, H3, and H5 - eg. Preserve Fernz Timber protection (03 349 4063) distributed by Prime Pine 03528 9134. Or Kopper Hickson's Tanalised Ecowood.
- Worst - LOSP (light organic solvents preservatives). (also known as SuraPine , Vasol, Protim) H1, H3
- Very Worst - CCA (copper chrome arsenic) H1, H3, H5.
Timber trims, beading, skirtings - paint finished
Timber should be sourced from sustainable sources such as plantations.
- Best - finger jointed pinus radiata certified from NZ plantation.
- Best - low formaldehyde MDF or MUF made from guaranteed NZ plantation timber - Carter Holt Harvey Panels MDF , Rangiora , Contact Geoff d'Auvergne 03 313 2736
- Next Best - finger jointed pinus radiata certified from foreign plantation.
- Next Best - MDF or MUF made from guaranteed NZ plantation timber - Carter Holt Harvey Panels MDF , Rangiora , Contact Geoff d'Auvergne 03 313 2736
Plywood
Timber should be sourced from sustainable sources such as plantations. Formaldehyde is off gassed by formaldehyde bonded composite boards. Formaldehyde is a carcinogen and so is contributory in the sick building syndrome. Products with low formaldehyde emissions should be preferred. Phenol formaldehyde is a low emissions formaldehyde.
- Best - plywood bonded with phenol formaldehyde and formed from guaranteed plantation timber - eg Eco plywood by Carter Holt Harvey
- Acceptable - plywood bonded with phenol formaldehyde - typically external grade ply
- Acceptable - normal plywood.
MDF
Timber should be sourced from sustainable sources such as plantations. Formaldehyde is off gassed by formaldehyde bonded composite boards. Formaldehyde is a carcinogen and so is contributory in the sick building syndrome. Products with low formaldehyde emissions should be preferred.
- Best - low formaldehyde MDF or MUF made from guaranteed NZ plantation timber - Carter Holt Harvey Panels MDF, Rangiora. Contact Geoff d'Auvergne 03 313 2736
- Next Best - MDF or MUF made from guaranteed NZ plantation timber - Carter Holt Harvey Panels MDF, Rangiora. Contact Geoff d'Auvergne 03 313 2736
Insulation batts
Wool insulation has lower embodied energy content. Glass fibre if allowed to enter the air supply can cause asthma and respiratory problems and so is implicated in the sick building syndrome.
- Best - Blended wool insulation bats (accredited types only) - eg Thermofleece R2.2
- Best - Fibreglass insulation batts - eg Pinkbatts R2.2
- Acceptable - polyester insulation only acceptable in locations where supply air will pass over the insulation.
Insulation board
CFC's , HCFC's and HFC's are all to a greater or lesser degree greenhouse gases and should be avoided.
- Best - expanded polystyrene ( all CFC and HCFC free)
- Best - CFC, HCFC and HFC free extrude polystyrene - eg Styrodur C by Forman Insulation
Joinery carcasses
Timber should be sourced from sustainable sources such as plantations. Formaldehyde is off gassed by formaldehyde bonded composite boards. Formaldehyde is a carcinogen and so is contributory in the sick building syndrome. Products with low formaldehyde emissions should be preferred. Although melamine is not an optimum choice, assume all are finished in melamine.
- Best - plywood bonded with phenol formaldehyde and formed from guaranteed plantation timber - eg Eco plywood by Carter Holt Harvey
- Best - low formaldehyde MDF or MUF made from guaranteed NZ plantation timber - Carter Holt Harvey Panels MDF, Rangiora. Contact Geoff d'Auvergne 03 313 2736
- Acceptable - MDF or MUF made from guaranteed NZ plantation timber - Carter Holt Harvey Panels MDF, Rangiora. Contact Geoff d'Auvergne 03 313 2736
Joinery finishes
- Best - Plantation / sustainable sourced local timber veneer. - eg Bestwood best pine, macrocarpa, eucalyptus, cypruses.
- Best - Sustainably sourced reconstituted timber veneer - eg Bestwood Reconstituted Veneer type 1 or 3 only.
- Best - sustainably sourced timber veneer from overseas - eg Bestwood FSC certified veneers.
- Acceptable - melamine
Sheet flooring
PVC is a material that has a highly polluting manufacturing process. It is also responsible for off gassing chemicals dangerous to human health and is therefore a component of the Sick Building Syndrome. It is also extremely dangerous in fire situations. Natural alternatives are preferable.
- Best - Linoleum - eg Marmoleum by Halstead Flooring Concepts
- Best - Rubber flooring - eg Mondo resilient Flooring by Jaydex International Ltd 09 444 1751
- Best - Ceramic Tile flooring (comparison price required)
- Worst - Vinyl Sheet flooring
Carpet
Natural materials should be preferred to synthetic materials. Products that the support the Environmental Choice labelling scheme can be trusted to be more environmentally friendly. Interface Industries have made significant efforts to reduce the environmental impact of their products and are a leading light for industry. They will also take responsibility for the recycling of their carpets on demolition.
- Best - natural wool carpet - Feltex Environmental Choice Range Commercial.
- Best - natural goat hair carpet - eg Tretford carpet distributed by Kim Crossan marketing 09 4733919
- Best - 100% recycled nylon carpet - eg Entrophy by Interface contact Rob Donze
- Acceptable - Interface nylon carpet with bitumen backing. - Price also required for leasing option.
Celing tiles
Natural materials are preferable to non - natural materials. Glass fibre ceiling tiles can result in high levels of glass fibre in the air supply. Glass fibre can cause asthma and respiratory problems and so is implicated in the sick building syndrome. Some types of glass fibre are also believed to be carcinogens.
- Best - Strawboard and woodwool (only suitable in certain locations - eg Stramtech Easiboard by Ortech Industries, Woodtex by Forman Insulation
- Best - Mineral fibre tiles - eg Armstrong tiles , Eurocoustic tiles all by Forman Insulation. Rockwool Rockphon distributed by Link Distributers 09 379 5061
- Worst - Glass fibre tiles - these should be avoided.
Paint finishes
Paint manufacture is a highly polluting industry. Paints whose manufacture is less polluting should be preferred. Paint also off gases a number of chemicals known to be dangerous to human health. Paint is therefore a principle component of the sick building syndrome.
- Best - Water based Silicate Mineral paints - eg Keim Ecosil or Keim Biosil distributed by Equus.
- Acceptable - Water based acrylic Environmental Choice Range - eg Resene Environmental Choice range.
Polyurethane
Polyurethane manufacture is a highly polluting industry. Clear finishes for timber whose manufacture is less polluting should be preferred. Polyurethane also off gases a number of chemicals known to be dangerous to human health. Polyurethane is therefore a component of the sick building syndrome.
- Best - Natural oil/wax based finish - eg OS Color hardwax oil. Natural House Company 03 328 9588. Maintenance issues must be considered.
- Acceptable - Water based low VOC polyurethane - eg Resene Environmental Choice range or Protecto by Tarkett Flooring.
Electrical / data cabling
PVC is a material that has a highly polluting manufacturing process. It is also responsible for off gassing chemicals dangerous to human health and is therefore a component of the Sick Building Syndrome. It is also extremely dangerous in fire situations.
- Best - PVC free cabling aka zero halogen, smoke free cabling
- Best - PVC free conduit.
Refer to electrical engineer for guidance on appropriateness of the various systems.
Pipework
PVC is a material that has a highly polluting manufacturing process. It is also responsible for off gassing chemicals dangerous to human health and is therefore a component of the Sick Building Syndrome.
- Best - Copper
- Best - polypropylene (also has very good insulating properties for hot pipe work) - eg Fusiotherm by Aquatherm NZ Ltd 09 570 7204
- Next best - polybutyline - eg Buteline 09 274 0716, or Dux Fast Fit by Dux Industries ltd 03 348 8713, or Polytherm Industries , Pro Fit by NT Leighton Hill Ltd 03 366 1877
Refer to mechanical engineer for guidance on appropriateness of the various systems.
Drainage
PVC is a material that has a highly polluting manufacturing process. It is also responsible for off gassing chemicals dangerous to human health and is therefore a component of the Sick Building Syndrome.
- Best - Ceramic - Hume industries 03 379 9640
- Best - concrete - Hume industries 03 379 9640
- Acceptable - polyethylene - eg I - plex Polydrain 0800 800 262
- Acceptable - polypropylene - eg Vulcathene by Plastic Systems 09 415 7120
Refer to mechanical engineer for guidance on appropriateness of the various systems.
In addition to material selection, decisions on the ability to reuse existing materials were carefully and consciously made. Where reuse proved unacceptable recycling of these products was carried out. Examples being:
- use of old carpets as mulch on native tree planting projects
- sale of reusable carpet to staff
- sale of ceiling tiles for lining a commercial workshop
- sorting for recycling of all demolition products
