Photos log hemp - Tiverton Campus 26 February 2015

1. Hemp demonstration action Tiverton Campus 26th
February 2015
Wooden frames were built prior to the training.
Ordinarily, the frame and hemp would be built on
a stone, brick or blockwork plinth to prevent
water ingress / damp rising. Due to the time of
year and the weather, and this being a training
exercise, we decided just to use wooden frames.
They were designed to be free standing so that
they could be reused for future training.
Wood used for the frames is 4x2. The frames are
2m long x 1m high, with 400mm spacing. This
replicated the size of wood and spacing that
would be needed in an actual build.
Fixing horizontal battening
Side panels cut to 200mm to allow
an overall depth of 300mm. The
horizontal battening placed along
the length across the main frame
is placed at approximately 600mm
spacing. This acts as a key which
provides extra strength to the
hemp wall. Without this, there is
no structural connection to the
timber frame.
Fixing the shuttering
Guide screws (deck screws) are placed along
with wooden spacers (wooden spacers are
not screwed in but made so they push firmly
into place). They act as support for the
shuttering and for setting accurate spacing
to allow for the overall 300mm.
Wooden spacers are removed once the
hempcrete reaches their level. Leaving the
Screws in place until shuttering is moved.

2. Explaining how the framing and shuttering works
Screws must not be left in as any metal fixings
left exposed to hemp and lime mix will rot. Any
metal fixing that will have contact should be
stainless steel.
Filling the pan mixer. Mix is 1 bag of hemp to two
bags of lime binder and approximately 60 litres of
water.
The hempcrete mixed ready
for use.

3. Pouring the hemp mix into the shuttering.
Spreading evenly and lightly tamping
down withpoles made by the participants
from the battening. The hemp must not
be pressed down with too much pressure
as removing to much air will affect how
thermally efficient it is.

4. Removing the shuttering to
reveal the finished wall

5. Hempcrete Wall – the finished product