What Does a Structural Engineer do, Why do I Need One & How Much Do They cost?

Reasons why you need a Structural Engineer

John Webster Architecture works with Structural Engineers in Dundee & Edinburgh on most of our projects. But it can be confusing as to who does what on a building project! You might think, hang on we already have an architect or a designer so why do we also need a structural engineer?  Good question, and one that requires a bit of explanation.

Here we go.

What does a Structural Engineer do?

On the surface it might be hard to tell the difference, think of it this way, a little more simplistic but the principle is the same, on a building site you need different trades, for example, you need a joiner and an electrician, they both do different jobs, you wouldn’t expect the joiner to wire your sockets or the electrician to build the walls, its similar with the design team, an Architect & the Structural engineer have different roles to play.

An architect or designers job is to design the building and to make sure that it looks great! & complies with current Scottish building regulations, which is a 500-page document covering everything from insulation to fire resistance.

On the other hand, a Structural Engineer must focus solely on the structural aspects of a building, certifying designs for building warrant.

A structural engineer designs a structure to resist loads such as wind and snow loads and other forces. They will specify timber or Steel sizes for lintels or joists as well as producing supporting calculations.

Further reading is available regarding loading if you click the link below.


Why do I need a Structural Engineer?

Most Scottish local authorities require an SER Certificate to accompany the structural design and building warrant application which means that the firm of Structural Engineers that you use will need to be an Approved Certifier of Design accredited with Structural Engineers Registration Ltd (SER).

So, as it’s important for your project to run smoothly arrangements are put in place for a Structural Engineer to be part of your team.

Here’s how we do it

Although we are independent and are not tied to any Structural Engineers, we do work with various Engineers on a regular basis.

We generally send the drawings (at an early stage) to 3 Structural Engineers to obtain quotes and get an idea of timescale as some Engineers can be booked for up to 4 months ahead.

Below we have listed the sequence of a project and added information to show at when the Structural Engineer becomes involved. Like most things in life, planning is essential to make the project run as smoothly as possible and avoid delays.

  1. Architecture firm appointed by client
  2. Design drawings finalized
  3. Planning application submitted (at this time we send the drawings to obtain quotes from various Structural engineers)
  4. Planning Granted (structural Engineer selected and appointed)
  5. Building warrant drawing prepared (In conjunction with Structural Engineer)
  6. Building warrant application submitted.
  7. Building warrant granted.


How Much Does a Structural Engineer Cost?

This is maybe a little bit like asking how long a piece of string is! It depends on what type of project it is. Below is a list of some examples (real life).

Typical costs for a Structural Engineer on a residential project


SER and design for removal of load bearing wall£595.00

SER and design for a bungalow Loft conversion

SER and design for a 2 storey Extension£1245.00
SER and design for a 4-bedroom house (approx. 220m2)£2500.00

Prices are subject to VAT at current rates.

So hopefully that has given you an insight into what a Structural Engineer does, why you need one & how much they are likely to cost!

You might find these resources below helpful:

Finally, if you would like to discuss your project further you can take up our offer to get your FREE 20 ‘Ask the Expert’ call.

  • Click here to arrange a call!


Want to Get in Touch?