GC Robertson and Associates can provide
structural design work within several different disciplines, see below
for more detail;
The complexity of
structural engineering work required for the construction of new
dwellings and the extensions and alterations to existing ones can often
be underestimated, for although in the main the structures are small in
civil engineering terms, an appropriately designed and well detailed
scheme can save time, reduce cost and simply make life less stressful
for all involved in the project. This is doubly important when someone
is living in the structure in question. With existing buildings time
taken to find out about the form of the existing construction including
any previous alterations is rarely wasted.
We have very wide experience of both new build and alteration works on
residential buildings from clay lump and traditional timber frame
through all kinds of masonry construction to timber panel construction,
and concrete / steel framed houses.
The requirements of
work on commercial and industrial buildings largely stems from the fact
that their function is paramount and often the building form simply
follows the required function. The structural design should follow this
principle to give a practical, buildable economic solution.
The commercial and industrial sectors are often less conservative than
the residential market in embracing recent construction technology and
the economic benefits this can bring.
Alterations to commercial and industrial buildings are often primarily
governed by the need to minimize disruption to the main activity of the
concern, and care and planning taken at the design stage can minimize
disruption during the work itself.
G C Robertson & Associates have long experience in both the
structural design of new commercial & industrial buildings and of
alterations to them from portal framed industrial buildings,
restaurants, schools, lifeboat stations to golf driving ranges.
Structural work on listed or
historic buildings can either be to deal with defects or to extend /
alter or change their use.
Any structural work to a Listed Building will require investigation to
determine the form of the original structure, how it works and its
capacity. In general the philosophy governing repairs and alterations
to listed buildings is to maximize the retention of the existing
structure and finishes, though there are wildly divergent approaches to
this all with their own benefits.
Using 'modern' techniques
e.g. steel plates, posts, resin injection etc. on traditional timber
structures can allow retention of more parts of an original structure
than replacement of like for like and can be seen to provide a more
'honest' repair - the repairs can be seen for what they are.
Minimum intervention. Modern
day methods of structural analysis and design Codes of Practice have
generous factors of safety built in and often existing buildings will
perform satisfactorily even though they may be woefully under designed
by modern standards. It is possible to take the view that if a building
has been in use for several hundred years it is bound to stand up for a
few more years and to keep any repairs / replacements to an absolute
minimum. This however can be taken too far and knowing when and how far
to intervene is a matter for engineering judgement.
The use of modern day
finishes e.g. cement render and modern masonry paints on traditional
timber framed buildings can promote decay, and the use of lime mortar
and other traditional finishes allows the timber frame and infill to
breathe but some conservation evangelists would have you believe that
traditionally finished buildings will never decay - this is simply not
practice recommends that repairs to oak framed buildings are carried
out in new green (unseasoned) oak which is much easier to work and is
less likely to have nails etc. embedded in it, also as the oak then
dries and shrinks it can lock joints together. In contrast however
recent advice on reducing construction waste is pushing the use of
recycled timber for such projects.
Very few historic buildings
have remained unchanged since they were built, most have been repaired
or altered at some stage, others repeatedly so that one can often find
a sixteenth century timber framed building hiding behind a Georgian
rendered facade or a Victorian brick facade. It is important to have an
in depth knowledge of the local traditions in construction over the
centuries to be able to read the way the building has been altered and
understand the likely construction forms at different times in order to
be able to design repairs and alterations that will work with the
It can be seen from the above
that repairs and alterations to listed / historic buildings require a
depth of knowledge of materials and building techniques beyond that of
the structural design of new buildings.
It is important that the
Conservation Officer of the Local Authority is consulted prior to any
work on a listed building to check whether Listed Building Consent is
required - see below (Statutory Background).
This short article gives an
overview of the common factors governing foundation design of
residential or small commercial buildings in East Anglia and a summary
of commonly used foundation types.
Most of East Anglia is relatively flat and is composed of either sands
or clays with adequate capacity to withstand the loads imposed on them
by low rise buildings, so on the face of it most foundation design in
this part of the world should not be particularly onerous and this is
indeed the case with the simple approach of digging a trench 1 metre
deep and filling it with concrete, sufficing in most cases. However in
the following cases this is not sufficient and special foundations can
Made Ground. Unlike the
North of England, East Anglia does not have a history of widespread
mining, but small pits and quarries for the extraction of sand, gravel
or clay were common and these were often subsequently infilled with
soil or refuse. These pits are not always picked up by site
investigations unless the site is peppered with boreholes or trial
holes though they are sometimes recorded on historic Ordinance Survey
maps. Old wells are often found during work on domestic extensions and
they were, unsurprisingly placed as near as possible to the back of the
original building and deep sewers or surface water drains can also be
With all of these, alternatives
to conventional foundations can be required and we can provide designs
for a variety of special foundation types to cover these situations.
If you are new to the world of
building construction it can be useful to have a broad outline of some
of the legal hoops that need to be jumped through in order to construct
or significantly alter a building.
Planning Permission - If you are proposing to construct a building or
to modify a building so as to alter its external appearance Planning
Permission is likely to be required and advice of the Local Authority
should be sought.
Local Building Control Building Regulations Approval - There are a
myriad of government regulations concerning the details of design and
construction of buildings and these need to be complied with when
constructing or altering a building. Part of these regulations govern
structural design and construction requirements, and normally an
application is made to the Building Control section of the Local
Authority to gain approval of the design, and then the construction is
checked on site at various stages by a Building Inspector.
Listed Building Consent - Some existing buildings, usually of special
architectural or historical interest are listed and for these any
significant extensions or alterations (even internally) require Listed
Building Consent. The Conservation officer of the Local Authority can
advise on whether a building is listed and if so what is required to
gain consent. More details of this are given in the article above on
Structural Design for Listed / Historic Buildings.
Construction Design & Management (CDM) Regulations - see CDM Co-ordinator.