Most self-builders research the market place and make an informed decision on their preferred form of construction. However, some do not and can be easily influenced by uninformed hearsay. As a consequence a number of myths have arisen around timber frame construction.
This myth suggests timber frame homes are unable to stand up to high winds. Within the UK, the further north you are the more severe wind speed design criteria become, varying from 20 metres per second (m/s) in London to 29 m/s on the Isle of Lewis and Orkney Islands (see map). These maximum gust speeds are only likely to be exceeded once in 50 years. The annual mean wind speed across the north of Scotland, for example, is about 10 m/s. This approximates to 22mph.
Cottage Kit Homes are individually certified by an independent structural engineer and, in standard form, are suitable for any UK mainland or island location.
Timber frame construction affords some flexibility which makes it particularly suited to exposed locations where extreme wind forces may otherwise result in cracking. For this reason timber frame is the preferred form of construction in countries subjected to seismic activity.
This myth arises due to the relative lack of solidity between a timber frame house and a masonry (brick / block) built house. Timber is a natural insulator and combined with the insulation materials fitted in the frames offer greater thermal efficiency than the equivalent thickness of masonry. Statutory requirements for ever more energy efficiency mean new homes have to be virtually airtight. This is far easier and cheaper to achieve in a timber frame home. Improved airtightness means homes are easier, cheaper and quicker to heat.
Cottage Kit Homes feature our renowned ‘EcoWall’ specification for external walls which achieve an impressive U-value of 0.15W/m2K. Upgrade to our ‘EcoWall+’ specification and this lowers to 0.11W/m2K. Typical airtightness tests achieve an excellent air infiltration rate of less than 5m3/h/m2.
This myth is based on the perception that timber frame homes contain a lot more wood than masonry built homes. In general there is no difference in the timber content of floors, roofs, internal partitions, doors, kitchens, etc. in a timber frame built house compared to a masonry built house The main difference occurs in the external wall construction. In a typical timber frame external wall, with a masonry outer leaf, the timber content is less than 9% by volume. Moreover, the timber is deeply embedded in the overall wall construction and protected by fire resistant materials such a plasterboard.
This myth is again based on the relative solidity of timber frame homes compared to masonry built homes. Although timber frame construction may appear open, it is filled with insulating materials which not only provide better thermal performance but also better acoustic performance. In external walls noise reduction depends on the quality of windows and doors. In internal walls noise transfer between rooms is greatly reduced by the provision of sound deadening materials within the wall construction.
This myth is again based on the perception that timber frame homes contain a lot more wood than masonry built homes. As stated under Myth 3, the increase in timber content is actually less than 9% by volume and only in the external walls. All structural timbers are kiln dried to reduce moisture content, stress graded to meet engineering standards and pressure treated with preservative to protect against rot and fungal attack. This ensures structural stability and durability.
It should not go unnoted that in some countries timber frame is the preferred form of house construction – Scotland – 70%; Australia – 90%+; Canada – 90%+; Japan – 45%; Norway – 90%+; Sweden – 90%+; USA – 90%+. It is estimated that across all the developed countries, timber frame accounts for around 70% of all housing stock, representing some 150 million homes.
If you have any other concerns about timber frame construction don’t hesitate to contact us.
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