Timber iQ October - November 2019 // Issue:46 | Page 17

ASSOCIATIONS
Choosing the right thatching contractors
By the Thatchers Association of South Africa (TASA)
Choosing a thatching contractor is a crucial step, and it is important
to make sure the contractor is registered with the Thatchers
Association of South Africa (TASA).
T
Given the above, the architect, at sketch plan stage, should
consult with an authority in the industry to rectify or
modify the design ensuring optimum stability of the
structure and to maximise water runoff due to correct roof
slopes and position of valleys in relation to the overall
roof design.
To analyse a thatch structure, the engineer will require a
structural design of the proposed roof to calculate pole sizes
and the number and diameter of bolts required for the
varied connections.
Very often today, thatch roofs are constructed without
structural drawings and analysis and as a result are, after the
fact, difficult and expensive to modify – sometimes
impossible. With detailed drawings, the architect can also
assess the aesthetics of the structure and in conjunction with
the engineer, alter the detail to the benefit of the client.
he thatch roof industry is a specialised field and
choosing the cheapest contractor might be the most
expensive mistake an owner can make. Thatchers
registered with TASA all comply with the requirements and
standards of a quality thatch roof.
There are basic principles unique to thatch roofs that need
to be adhered to. To obtain the optimum life span from the
roof, certain criteria, not obvious to non-specialists, need to
be followed such as roof angles, the position and angle of
valleys relative to other features of the initial concept. The
floorplan and elevations of the building affect the structural
design of the roof often affecting the structural stability of
the roof especially awhere there are varied ridge heights and
roof junctions. These junctions do not allow for the
placement of effective bracing and very often there are no
support walls to counter the lack of efficient bracing.
Thatchers registered with TASA all comply with the requirements and standards of a quality thatch roof.
www.timberiq.co.za
// OCTOBER / NOVEMBER 2019
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