Do I need structural calculations?

Structural calculations are essential in construction, they ensure proposed designs are functional and meet the requirements needed for a safe and stable structure. Required by building regulations, these calculations are often but not always, needed when renovating your home. A building control officer will request calculations and associated drawings, which can include things such as beam connections, load analysis and steel specification to confirm your proposed works meet all standards for a safe property. Your builder will also need the calculations as it shows them important information such as foundation details, steel size, beam connections… the list varies project to project.  So, when do you need structural calculations? How do you get structural calculations? And most importantly, does your extension or renovation project need structural calculations?

Structural calculations must be completed and signed off by a qualified structural engineer. They will differ in content depending on the project but will include information on the structural elements of your build (walls, beams, columns). They will also analyse the reinforcements, materials and in some cases environmental impact of your project. Alongside the technical drawings in your Building Regulations Pack, they will be used by your builder throughout the build process. They are needed by your building control officer, who will want to review both the technical drawings and structural calculations prior to the commencement of works to ensure the proposal is compliant with current building regulations.

Structural calculations are essential for your home to meet building regulation standards. Building Regulations are separate to planning permission, they deal with the approval of two totally different aspects of your extension. A planning application is made to seek approval to build, whereas Building Regulations are to ensure the safety of that build and will look at things such as structural integrity, fire protection and energy performance. Not obtaining building regulations approval can risk you being fined, potentially having to demolish the work and can affect your ability to sell the property in the future.

Do I need structural calculations? If you are extending your property or undertaking a loft conversion you will need structural calculations. You will also need them if you are removing a chimney breast or a load bearing wall. You are also likely to need them if you are installing a door or window. It’s important to note that even if your build doesn’t need steel reinforcements it still requires a qualified engineer to check the proposed design and confirm this is the case – and your building control officer might request formal confirmation from the engineer.

TIP! If you’re removing a chimney breast from your property it will require structural calculations. It it’s also important to remember that any work involving the alteration of a gas appliance, or its components, must be undertaken by a Gas Safe Register engineer.

To know if your build will require steel, we undertake a thorough survey to assess the property and produce CAD drawings that our engineer can use to determine if steel is needed. Not all architects have a structural engineer within their team, however at Home Tales we find having an engineer on our team means smooth communication and designs that are neither unsafe or over-engineered (risking the finish of the property or unnecessarily inflated build costs.)

What should you do if you have architectural plans but no structural calculations? At Home Tales we often work on our Build Regulations Packs alongside the design element of a project, however we recognise in some case that renovators work with architects who simply supply the designs but leave them without the structural calculations that will allow them to build. In those situations, we’re happy to work with you on a Build Regulations Pack to make sure your building control officer and builder have everything they need to move forward with your project.

Still feeling stumped by structural calculations? Our friendly team are always on hand to help. You can get in touch with us today on 0207 043 2378 or email us at to ask any questions or arrange a call from one of our renovation experts. You can also book a consultation to discuss your project and receive a free, no obligation quote via our live diary here.

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