Eco Priority Guide: Doors

Eco-Priorities

The following issues relate to both potential positive and negative issues associated with each product class:

Priority Order	Solid timber	Coated hollow-core	Hollow core	MDF door	Structural Glass Door
1	Habitat	Habitat	Habitat	Energy	Resources
2	Health	Energy	Health	Health	Energy
3	Energy	Toxics	Energy	Toxics
Red Lights	Check timber source	Check timber source	Check timber source	Check timber source
Example	Hardwood or softwood door	Vinyl coated hollow core front foors	Interior grade door	Interior/ exterior doors	Glass commercial door

Overview

In residential buildings doors are one of the weakest points in the buildings’ thermal performance. Australian’s typically use relatively thin (35mm) solid doors, which give poor thermal insulation, and very poor edge sealing. One of the most important things we can do with a door is simply put quality air-stripping around its perimeter.

Doors are also a major user of imported rainforest timbers. The source of these timbers is generally poorly understood or completely unknown.

Quick Guide

Solid timber
For: · Natural, renewable product · Low energy production · High-value product with good potential for reuse · Can use 100 percent recycled content · Highly durable, maintainable · High strength	Against: · Timber may be sourced from highly vulnerable rainforests · Relatively material intensive
Hollow Core
For: · Majority construction from renewable resources · Lightweight, inexpensive · Incorporates low-grade wood, often by-product from other production lines	Against: · May contain timber from vulnerable areas or highly vulnerable areas if ply faced · Reuse unlikely · More readily damaged than solid timber
Coated Hollow-core
For: · Cost-effective · Low maintenance	Against: · Reuse possible but generally unlikely · Composite material that makes recycling impractical · Energy, VOC and toxicity component from the sealant coating
MDF (may be coated or uncoated)
For: · Most likely not from vulnerable forests · Cost-effective · Low maintenance	Against: · Reuse possible but generally unlikely · Composite material that makes recycling impractical · Product will offgass · Energy, VOC and toxicity component from the sealant coating
Glass Door
For: · Not sourced from vulnerable forests · Visual access to interior	Against: · Poor thermal performance · Relatively high energy requirements

Making a Decision

Commentary

If a timber door guaranteed not to be from vulnerable or high conservation forest types cannot be sourced, the use of a composite door represents a good environmental alternative. It uses small quantities of a tough, waterproof facing and often low-value wood products. MDF-based doors are often Australian made, generally use plantation pine in their construction. However they use urea-based formaldehyde glues which will offgass at low levels for a long period, even when painted.

At present the range of doors (including hollow-core) not incorporating imported rainforest wood products is very small. The presence of a pinkish-brown laminate of timber (sometimes visible in the end grain) often denotes the use of luan, a cheap imported rainforest species. It should be noted that all commercially available door stiles (the door surrounds) are made of imported rainforest species such as Meranti, a timber sourced from at-risk rainforests in the Asia-Pacific.

Internet Resources

Friends of the Earth UK ‘Good Wood Guide’

A global guide to forest and timber species conservation status from a leading international conservation group in this field.
Follow the links from www.foe.co.uk (search for ‘Good Wood’).