Civil Engineering Reference
In-Depth Information
Loadbearing in a wet climate
you can appreciate how quickly a person
with a forklift truck and telehandler machine
can build a new DIY superstore. Obviously
there's a little bit more complexity to the
design than this, but you get the picture!
Over the years, the main disadvantage of
the loadbearing technique - namely how to
keep the straw dry throughout the whole
building process despite the sometimes
prolonged wet weather of the UK and
Ireland - has been dealt with. Ways we can
address this issue are as follows.
Basically there is no real limit to design or
size when using loadbearing techniques.
We have built circular and curvaceous
buildings, and detached and semi-detached
two-storey buildings using this method. It's
all about understanding the material and
having a creative approach to problem-
solving.
•
Prepare everything in advance (prefabric-
ation) so the whole building goes
together quickly once you start, like
building with Lego. The vulnerable time
of exposure to the weather, and the need
to keep it covered with tarpaulins, can be
reduced to a few weeks.
Infill (also called post and
beam or timber frame)
•
For small buildings, build underneath a
marquee or large tent.
Next to loadbearing, this is the other 'tradit-
ional' way of building with straw. It was
developed in the USA in the late 1970s, as
their construction industry was familiar with
it as a practice. In this method, the weight
of the roof is carried by a timber, steel or
concrete framework; the bales are simply
infill insulation blocks between the posts,
and a key for plaster; they are not used
structurally. You might make this choice
because you like the look of timber and you
want to use its beauty in your design, or
because you are going for something really
ambitious with large openings and spans,
and a loadbearing building just won't do
it. This method also has the advantage of
giving peace of mind to clients and those
professionals (architects, engineers and
building inspectors) who aren't quite ready
to accept just what straw can do as a building
material. It is often the preferred option
for architects, as the structural concepts
are not innovative and rely on an already-
•
For larger buildings, increase the height
of the scaffolding (needed to build the
walls and roof), add a temporary roof
over the top, and cover in the sides. This
level of protection is required for the lime
render anyway, so it can be cost-effective
to protect the whole building, ensuring
there will be no time lost due to the
weather for any aspect of the building,
not just the straw, at any stage.
•
Use an impressive-compressive method
(see pages 31-34) and use the floor or
roof as the main weather protection.
Loadbearing for warehouses and
retail units
Large open spaces can be built very quickly
and effectively using mini Heston or Quad
bales. At around 8' long and 2' high per bale
