CHRIS WOOD

Taking sides in the thatching controversy

Thatch has a promising future as the most sustainable of roofing materials, but its users disagree about the lessons of its history.

There can be no more ecologically sound and sustainable building material than thatch, at least in theory. Traditionally, it was grown with only the use of natural fertilisers and then harvested, prepared and fixed on to roofs and ricks by local thatchers. This picture has of course changed, notably since the Second World War and the issue of materials has become particularly vexed. The problem for local authorities is how to get reliable information on growers and advice on technical issues, but this is about to change.

English Heritage’s research into the history of thatching1 shows a tradition based mainly on straw, with water reed being confined to estuarine areas. Great dexterity was shown with the use of whatever was grown, with all sorts of different materials being used2, but all of it involved the minimum use of transport. Nowadays, of course, even traditional straw has to travel distances, as there are few farmers or growers who produce the materials ostensibly for thatching, despite it being relatively lucrative.

Experienced thatchers often grow their own straw or use the same farmers, and they tend to have strong preferences for particular types of wheat. Older strains such as Squareheads Master, Rampton Rivet and Little Joss are still used but currently it is illegal to trade in seeds that are no longer on the National Seeds List. Currently only two types of wheat are on the list:

Mans Huntsman and Mans Widgeon. When the former was threatened with delisting last year, English Heritage provided temporary financial support to ensure its immediate continued survival, but it remains threatened.

There is a conflict between, one the one hand, those wanting to see a return to the use of the traditional pattern of locally produced straw and the retention of

the styles of thatching that these materials dictated and, on the other, those who dispute some of the history of thatching and regard the ‘tradition’ as being one in which the thatcher is free to use whichever material or style they or their client wants. Greater reliability, availability and longevity are claimed for imported water reed by its supporters, with the result that more and more is imported. The imports are mainly from Eastern Europe, along with veldt grass from as far away as South Africa.

One of the biggest problems is vouchsafing the quality of an organic material. Premature degradation has been regularly cited in the past, and has affected both straw and reed. This was not such a problem when patch repairs were more prevalent and regular but nowadays, with most jobs involving a complete rethatching, this can be very expensive. So far a scientifically valid approach to testing the quality of thatching straw or reed has not been devised. Perhaps the best suggestion to date is to provide some system which records provenance, whereby the grower accurately records details such as the time the seed was sown, the type of soil and the amount of nitrogen added. Such a system would need to be impartially administered. Although it would not guarantee quality, it would at least give the thatcher and owner some comfort about the product.

Longevity of thatch continues to be fiercely argued. Examples of long straw, combed wheat reed and water reed lasting over 50 years are well known. Much depends on the quality of the product and its growing regime, the ability of the thatcher, and the location and siting of the roof. Experienced growers cite examples of inspecting a failed thatch after less than ten years and then finding another roof, rethatched by a different thatcher using straw from the same field, in

Growing trials of old

English wheat varieties

at Reading University.

Photo by John Letts

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CONTEXT 73 : MARCH 2002