So you want to buy a thatched house?

Background Thatch was the most common form of roofing in Britain until the end of the medieval period, although it was still common in many rural areas until the mid nineteenth century. Today in England there are about 24,000 listed thatched buildings - a decrease from around one million in 1800 and 35,000 in 1960. Thatch is now enjoying an increase in popularity again, partly due to its perceived environmental qualities and as regions become more aware of the need to retain their rural character in order to encourage tourism and so on. There are distinct regional characteristics in the method and style of thatching ridges, gables and eaves, so the roofs in East Anglia will differ to those in the South West for example, and thatchers may have their own style.

The layer of thatch on a roof is at least a foot thick. In the case of The Clergy House in Alfriston, as shown in the pictures, the final new thatch will be one foot thick, on top of a layer of old thatch about the same thickness, called the base coat. This layer of old material is always left and new thatch placed on top. It is only the top layer that is exposed to the elements - roofs must have a minimum pitch of 45 so rain, snow and sleet travels down this steep slope before it sinks into the thatch and reaches the rooms below. Thatch also provides good insulation as tiny pockets of air are trapped within the stems of the vegetation.

There is no single national body which represents thatchers, but there is The National Council of Master Thatchers Association as well as county associations with standards for members, such as the Rutland and Leicestershire Master Thatchers Association or the East Anglia Master Thatchers Association. A National Training Centre in Northamptonshire takes on 12 students (of any age) each year who serve a five year apprenticeship, although it can take a further five years to become recognised as a Master Thatcher.

Thatching materials and methods The Clergy House is being rethatched with Long Straw which in this case is an old variety called Maris Widgeon which has long stems and is organically grown in Leicestershire by specialist thatch growers. The less nitrogen in the straw the better it is for thatching, and the more durable. Long Straw is harvested in the old fashioned way with a binder, before being gathered into a sheath and threshed. It is then drawn by hand into bundles called yealms. Long Straw requires more preparation on the ground and has external hazel rodding at the eaves and gables which is not often seen on reed thatches. Although The Clergy House was being completely rethatched for the first time in about 70 years, a number of repairs have been made in the interim and Long Straw thatching is more easily attacked by birds, so it is often netted to prevent this problem.

Other materials commonly used in thatching are Combed Wheat Reed and Norfolk Reed. Many thatchers are skilled in working with different materials, but may prefer one to the other. Local traditions and styles will also dictate what material is chosen as well as the application method and how various features on the roof are treated. Reed thatches were common along the coasts and in marshy areas, where the water reed was readily available. Norfolk Reed refers to reed harvested in the Norfolk fens. So that it doesn't shrink once in place, reed must be dried thoroughly before it is gathered into bundles (approximately 24 inches wide and 3 to 7 feet long) and attached to the roof frame.

Although The Clergy House hasn't been completely rethatched in 70 years, the life of a thatch will depend on the pitch and design of the roof, type and quality of thatching material, geography, topography and the skill of the thatcher. General maintenance includes keeping trees away from the thatch, not allowing climbing plants to grow into it, and avoiding disturbance to the thatch by climbing on it or laying a ladder on it. The ridge may need rethatching every 15 years. Correct and prompt repair and maintenance will significantly extend the life of a thatch.

Employing thatchers Thatchers work all year round, but prefer weather which is not too wet, and not too windy. They can be booked two or three years ahead, so you need to plan your repairs or rethatching! Quotes and so on are based on the area of the roof - The Clergy House is approximately 2500 square feet of thatch, which is 7-8 tonnes of straw, and is expected to take 12 weeks to complete, weather depending!

If you do need to rethatch or repair an existing roof, it is a good idea to contact the conservation officer of your Local Authority who will be able to advise on any consents needed, local policies and specific requirements about the materials to be used. Always get three quotes and ask the thatchers to show you examples of their work. Make sure that you have a physically measurable specification in the estimate (the area of the roof, see above) and check the thatcher has public liability insurance. Thatchers are frequently booked up some time in advance so you might have to choose your thatcher and plan to have your roof done before it gets really bad. If you leave it late, get a temporary fixing job done, but don't accept inferior work from someone who happens to have the time to do yours immediately.

Living under thatch Thatch is a lovely environment to live under - and it is an environment for lots of living things! We can sit upstairs and look out the windows and watch little mice scurrying aboutbut when they come inside in the autumn and run around in the space behind our heads at night then we have to do something about it. It is warm and cosy, and ever so quiet (apart from the odd mouse) - we can't hear the rain on the roof, and when it is windy we are secure thinking that our house and its various thatched roofs have been there for centuries. Apart from the obvious expense of having it rethatched every so often I would definitely recommend the experience, and if we ever managed to construct a new environmentally friendly house, then we would definitely consider thatch for the roof.

For more information: Small Farm Training Group (www.sftg.co.uk) www.thatch.org.uk Shire thatchers, Dorset 01747 811175 www.eamta.co.uk www.nationaltrust.org.uk and The Clergy House, Alfriston 01323 870001