NGfL CYMRU GCaD
STRUCTURAL TIMBER
FRAMING
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STRUCTURAL TIMBER FRAMING
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STRUCTURAL TIMBER COMPONENTS
Timber should
be bought from
sustainable
sources.
Such timber is
stamped with
the symbol of
the accrediting
body.
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STRUCTURAL TIMBER FRAMING
NGfL CYMRU GCaD
TIMBER STRENGTH
Timber is stamped according to it’s strength properties, as
described below:-
Timber Species
British Standard
Quality
Reference
Strength Grade
Condition
Certification Authority
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STRUCTURAL TIMBER FRAMING
NGfL CYMRU GCaD
Structural components include pre-fabricated
frames, wall panels, joists and roof trusses.
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STRUCTURAL TIMBER FRAMING
NGfL CYMRU GCaD
The design of structural members takes into account:
Dead loads - which includes weight of the actual
building, such as bricks, tiles and timber.
Imposed loads – machinery, furniture etc.
Live loads – the weight of people in the building.
Snow and wind loads – when it snows, additional
loading is imposed on the roof, and wind loads occur
in high winds.
Loads are illustrated on the next slide
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STRUCTURAL TIMBER FRAMING
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STRUCTURAL TIMBER FRAMING
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Descriptions of the manufacturing process of
structural elements follow:-
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STRUCTURAL TIMBER FRAMING
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Factory-made
components result in
high levels of repetition,
accuracy and quality.
This leads to cost
savings during
construction.
Timber components for
a roof truss are laid out
on a jig, as shown right.
Each component is precut to the exact
dimensions required.
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STRUCTURAL TIMBER FRAMING
NGfL CYMRU GCaD
Timber parts are
fixed together
mechanically,
using toothed steel
plates.
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STRUCTURAL TIMBER FRAMING
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Studs (verticals) and
sole plates are laid
out to exact
dimensions, and
nailed together.
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STRUCTURAL TIMBER FRAMING
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The panel head is
offered up to the panel
frame. The head is
fixed with pneumatic
nail guns.
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STRUCTURAL TIMBER FRAMING
NGfL CYMRU GCaD
Right – nails fixed to timber.
Below – Pneumatic nail gun
and nail cartridge.
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STRUCTURAL TIMBER FRAMING
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Right - plywood is then
nailed to the frame.
Left – a breather membrane
is placed over the plywood.
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STRUCTURAL TIMBER FRAMING
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Bands are stapled to
the panel to mark the
positions of studs. This
helps tradesmen on
site to establish fixing
points for other
building components.
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STRUCTURAL TIMBER FRAMING
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JOISTS
Joists are structural
components that
span the width of a
building.
Finished joists,
awaiting delivery to
a construction site,
are shown left.
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STRUCTURAL TIMBER FRAMING
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Roof trusses, delivered to site and awaiting fixing.
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STRUCTURAL TIMBER FRAMING
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A timber framed building under construction.
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The foundation layout of a timber framed building is
shown on the following slide, and construction methods
of this type of foundation also follow.
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STRUCTURAL TIMBER FRAMING
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Concrete blinding
Polystyrene shuttering
Steel reinforcements (rebar)
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STRUCTURAL TIMBER FRAMING
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STRUCTURAL TIMBER FRAMING
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STRUCTURAL TIMBER FRAMING
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STRUCTURAL TIMBER FRAMING
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STRUCTURAL TIMBER FRAMING
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Timber beams & joists
form the
superstructure
In the above image, a steel frame connects the timber superstructure to the
foundations. The red arrows indicate where columns are bolted to the
foundations. A more detailed image is shown on the next slide.
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STRUCTURAL TIMBER FRAMING
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Joists – will be fire protected
by plasterboard before the
building is occupied
Steel beams –
fire protected by
sprayed on
intumescent paint
Block work: forms part of the
structure, and offers fire
protection to steelwork
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STRUCTURAL TIMBER FRAMING
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Load carrying components are doubled in size and transmit
building loads to the foundations: a close-up is shown on the
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following slide.
STRUCTURAL TIMBER FRAMING
NGfL CYMRU GCaD
Studs
Noggins
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Prefabricated components are marked with their locations. This
speeds up construction time and reduces construction costs.
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STRUCTURAL TIMBER FRAMING
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Stud walls are fixed in position to form separate spaces. These will
eventually be fire protected by plasterboard.
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Once stud walls are fixed, first
fixing for plumbing and power
can take place.
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STRUCTURAL TIMBER FRAMING
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As prefabricated components arrive, rapid construction follows.
The above image shows the view looking down a communal
corridor of an apartment block, whilst under construction.
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STRUCTURAL TIMBER FRAMING
NGfL CYMRU GCaD
A vapour barrier, used to stop rain water entering the building, is
fixed externally.
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STRUCTURAL TIMBER FRAMING
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Battens are fixed over the vapour barrier, and insulation is fitted between
the battens. Cement render is applied to provide an external finish.
Colour pigment can be included in the render (known as a through-colour
render), or the render can be painted after curing.
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STRUCTURAL TIMBER FRAMING
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Large items, such
as roof trusses are
lifted into place
with a crane.
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STRUCTURAL TIMBER FRAMING
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Roof trusses
awaiting fixing.
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STRUCTURAL TIMBER FRAMING
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Roof trusses fixed in place, ready for roofing contractors.
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STRUCTURAL TIMBER FRAMING
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Structural flooring
and wall panels,
stored on site and
ready for fixing.
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