Roof Structure - Topic Home



In the Middle Ages the roofs of substantial houses were mostly made from hardwoods. This was not just a matter of choice - apart from Yew and Scots Pine, softwoods did not exist in this country. Most roofs comprised a series of sloping timbers, known as rafters, supporting a covering of tiles, slates, or thatch.  
During the 17th century the use of timber framing fell into decline - largely because of the risk of fire in our growing cities. By 1700 new houses in towns and cities were built in brick or stone. The Queen Anne style was soon followed by the terraced houses of the Georgians. These houses still had roofs made from timber, although by this time softwood, mostly imported, had replaced the use of hardwoods. The term 'deal' was used to describe suitable timber from Scandinavia (ie a good 'deal') - this was a generic term which described a variety of coniferous species.
The nature and construction of timber roofs barely changed during the next 200 years and it was not until the end of the Second World War in 1945 that significant changes in construction occurred. In the years following the War there were substantial shortages of building materials; there were also shortages of skilled labour. Prefabrication was seen as one solution to both these problems. Through careful design, light roof structures could be created which were simple to erect and which did not need skilled labour. Modern volume-house builders still use prefabricated trussed-rafter roofs developed from the early post War designs. 
On one-off developments it is still common to find traditional or 'cut' roofs. On these roofs the traditional skills of the carpenter are still in demand. They are not necessarily more economical and they are certainly not quicker than trussed rafter roofs. However, they may suit the working practices of the developer/builder and they are very adaptable and do not require the engineering and fabrication input of a third party.  
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