Why do I need a Structural Engineer?
So, you have got planning permission and you have organised a builder. Just before your builder starts on site you get told you need a ‘Structural Engineer’. “A what?”, you say. “Design of steel beams and foundations? Haven’t the Architect and Builder already done that? Isn’t that what I paid for?”
Well, sit back, relax and let us explain…
The Architect designs the building in terms of general aesthetics, the spaces created and how they work for the proposed building users - be they a family or a business. This is in order to meet the clients needs and obtain Planning Permission. After which, the architect may be employed to specify the construction details of the project, including the fire, acoustic and thermal properties of the proposed buildings, to meet the appropriate Building Regulations.
“And, then the builder then builds from the architects drawings..?”
Well, not always. The architects’ drawings do not cover how the building has to stand up. They do not cover Building Regulations Part A - Structures. Part A is concerned with the building standing up to the wind loads, live load. snow loads as well as the self weight of the building materials selected.
So we produce the design of the structure that holds the building up, the builder who may have years of experience, will not carry the design responsibility for anything he suggests, so any advice provided you will not have any recourse against the builder, as this is not his speciality.
Any deviation from an architects or engineering drawing will invalidate the insurance, with no recourse back to the original designer.
Why do I need trial pits?
Why do we need trial pits..? not an other cost..? Well you are about to spend an awful lot of money on a new extension or house, the last thing you want to do it carry out trial pits.
As engineers we have available the basic geological data for the area the building is located in, however the data and the reality of a building site maybe very different so we need to see the ground to ascertain what the potential loading capacity of the ground is and how it will carry with the weather and the vegetation around the immediate site and beyond.
Take Clay, looks quite innocuous as a material, however, its potential to damage new and existing houses is determined by the design of the foundations, the ground can be subject to the seasonal weather and the water demand of trees around, we can advise on how to deal with the impact of the trees, and even if you cut the tree down you are not resolving the issue.
As the density of the UK increases so does the demand for housing, and we are using more and more brown field sites, we need to understand the previous use to understand the consequences on the ground. IE contamination can damage the growth of a child, or gas generated by organic material can build up under a property be that CO2 or Methane, both pose a risk to human health.
What is Building Control for?
So whats the difference between building control and a structural engineer..? Structural Engineers carry out the design and carry design responsibility for the information in the drawings , Esentially converting the information.
Building Control officers ensure that the building is constructed as precise the drawings. They have no Authority to change or modify the drawings without the authority of the Structural Engineer , assuring the project is built to perfection.