The conclusions of a new European Commission research report on the life cycle of uPVC should not be taken at face value. The report compares uPVC with its most commonly-used competitor manufacturing materials. It concluded that as far as windows were concerned, the life cycle analyses (LCAs) for the three main framing materials, uPVC, wood and aluminium were broadly comparable, and that design was more important than the choice of materials. The European Council of Vinyl Manufacturers has already claimed that the findings “confirm that uPVC is as good as any material”.

But on closer inspection the study is not as authoritative as it might initially seem. Its success depended on co-operation from outside sources and this seems to have been wanting. Of 262 contacts made by the researchers only 40 provided information.

So the report is not truly representative. Most of the information used was drawn from non-UK sources and a considerable amount from the plastics industry. Much of the data on windows also came from countries such as Germany and Austria which, unlike the UK, have a highly organised approach to recycling. As a result, it is easy to misinterpret the headline findings and miss the caveats in the detail.

But, while this report may be misleading and inevitably suffered from not having access to timber window life cycle analysis undertaken in France and the UK, it also highlighted deficiencies in information available from the wood sector. There are environmental consequences to the natural production of timber, its harvesting, drying and transport, and LCA models and studies of wood products are few and far between.

So there are two conclusions to be drawn from the EC report. First, that the crucial factor in producing a high quality window is design and timber is a superlative design material. Perhaps more significantly, the report highlights that timber-using industries need to support environmental and sustainability claims with the sort of hard data the plastics industry already has at its fingertips.