Do I Need a Structural Engineer for My Project

Many building projects require input from a structural engineer, but it is not always obvious when their involvement is needed. This page explains in simple steps what a structural engineer does, when you must appoint one, how their calculations fit into your design and Building Regulations, and what you can expect throughout the process.

1. What a Structural Engineer does

Their calculations are required for Building Regulations approval and are used by your builder to construct the project correctly.

A structural engineer will

• assess the existing structure

• design any new structural elements

• provide calculations and drawings

• ensure the work complies with Building Regulations

2. When you need a structural engineer

You will need a structural engineer whenever your project involves altering or supporting the structure of your home. Common examples include;

• Removing a load bearing wall

• Installing steel beams for a loft conversion

• Building an extension

• Creating large openings for bifold doors

• Removing a chimney breast

• Converting a garage

• Altering roof structure

• Underpinning or strengthening foundations

3. When you may not need a structural engineer

Some projects are non structural and do not require calculations. Examples include;

• Internal cosmetic changes

• Replacing kitchens or bathrooms

• Decorating

• Minor repairs

• Like for like window replacements

4. How the process works

The structural engineer will usually visit your property to inspect the existing structure. They will then prepare calculations and drawings that show how the new work must be supported. These documents are submitted to Building Control as part of your Building Regulations application. Your builder will use the calculations to install the correct beams, lintels or supports.

The process normally follows this order;

• Architectural drawings are prepared

• Structural engineer reviews the design

• Calculations and drawings are produced

• Building Control checks and approves the structural design

• Construction begins

5. Why structural calculations are important

Structural calculations ensure that your home remains safe and stable. They also protect you from future problems such as cracking, movement or failure of structural elements.

Without proper calculations

• Building Control may refuse approval

• Your builder may not know what size beams to use

• You may face delays or additional costs

• You may have issues when selling your home

Having a structural engineer involved gives confidence that the project is designed correctly from the start.

6. How much involvement a structural engineer has

The level of involvement depends on the complexity of the project. For simple work, they may only need to provide calculations for a single beam. For larger projects such as extensions or loft conversions, they may design multiple elements including beams, joists, foundations and roof supports.

Your architect and structural engineer work together to ensure the design is both practical and structurally sound.

7. Does the Architect's fees include the Structural Engineer fees?

Structural engineer fees are not included within our architectural fees. Every project is different and the cost depends on the structural engineer’s own assessment, the complexity of the design and the number of elements that require calculation.

We always include an estimated figure in our quotes so you have a realistic idea of the likely cost. However, the final fee is set by the structural engineer once they have reviewed the project in detail.

This keeps everything transparent and allows you to choose the engineer who best suits your needs.

8. Summary for homeowners

• A structural engineer is required for any project that affects the structure of your home

• Their calculations make sure beams, openings, foundations and other supporting elements are safe and compliant

• Building Regulations approval normally cannot be granted without structural calculations

• Builders rely on these calculations to price and construct the work correctly

• Structural engineer fees are not included in our architectural fees, although we provide an estimated figure in our quotes

• Getting the Structural engineer onboard early helps avoid delays and keeps your project running smoothly