Columns in extensions and infill frames
- RC columns to support steel beams where walls are removed in extensions or refurbishments.
- Checks on loads from RSJs, point loads and eccentricity where walls or edge beams connect.
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Reinforced concrete design • Columns and frames
Reinforced concrete column design – safe, buildable details for UK projects
We design reinforced concrete columns for extensions, frames and new builds. Axial load, bending, buckling and fire resistance are checked so your drawings, calculations and bar schedules are ready for Building Control and your steel fixer on site.
Every reinforced concrete column design is produced by an experienced structural engineer using UK design codes and practical rules of thumb for bar layout and cover.
- Columns checked for axial load, bending, slenderness, buckling and second order effects.
- Clear bar layouts, lap lengths, links and cover so the steel fixer knows exactly what to tie.
- Fixed-fee reinforced concrete column calculation packs ready for Building Control and warranty providers.
We work with homeowners, architects, steel fabricators and contractors across the UK, providing reinforced concrete column designs that tie in with beams, slabs and foundations.
Reinforced concrete column design – what we check before sizing your columns
We make sure each reinforced concrete column works structurally and practically with the beams, slabs and foundations it supports.
Multi-storey frame columns
- Internal and edge columns carrying slab and beam loads over several storeys.
- Slenderness, buckling and second order effects checked using appropriate effective lengths.
Basement and retaining columns
- Columns that also act as part of a retaining wall or basement box.
- Combined checks for vertical load, bending from soil pressure and frame action.
Transfer and heavily loaded columns
- Columns supporting high point loads or transfer beams from upper storeys.
- High reinforcement ratios, anchorage and punching checks around column heads.
Edge, corner and wall-line columns
- Columns near openings, cladding edges or at the end of frames with high moments.
- Detailing of links, starter bars and lapped bars for good site buildability.
Checks to existing columns
- Assessment of existing reinforced concrete columns where loads are changing.
- Advice on strengthening options such as jacketing or adding new columns if needed.
Key checks in reinforced concrete column design
These notes summarise the main questions we work through when designing each reinforced concrete column.
Axial load and bending
Column loads from beams and slabs.
Unbraced or braced frame assumptions.
Interaction of axial load and bending in each direction.
Column size and bar area chosen so utilisation stays within safe limits.
Unbraced or braced frame assumptions.
Interaction of axial load and bending in each direction.
Column size and bar area chosen so utilisation stays within safe limits.
Slenderness and buckling
Effective lengths based on support conditions.
Slenderness ratio checks to decide if second order effects are important.
Creep, sway and stiffness of the frame considered where relevant.
Slenderness ratio checks to decide if second order effects are important.
Creep, sway and stiffness of the frame considered where relevant.
Detailing and fire resistance
Cover, bar diameters and link spacing set for the required fire rating.
Anchorage, laps and bar curtailment shown clearly on details.
Practical cages that steel fixers can tie without congestion at beam-column joints.
Anchorage, laps and bar curtailment shown clearly on details.
Practical cages that steel fixers can tie without congestion at beam-column joints.
Information we need to design your reinforced concrete columns
Good information in means fewer assumptions, quicker designs and fewer queries from Building Control and the site team.
Architect and engineer drawings
- Plans, elevations and sections showing column positions and storey heights.
- Any existing frame or beam information if this is an alteration or extension.
Loads and frame information
- Dead and imposed loads from floors, roofs and walls supported by each column.
- Details of any frame analysis model, or we can calculate line and point loads ourselves.
Concrete, reinforcement and exposure
- Preferred concrete strength class and reinforcement grade if known.
- Exposure class and fire rating requirements so we set cover and bar sizes correctly.
Foundations and ground information
- Foundation type and bearing capacity so column bases can be detailed properly.
- Any restrictions on column size due to architecture, cladding or services.
Reinforced concrete column – frequently asked questions
Short answers to the questions we hear most often about reinforced concrete column design on UK projects.
What is a reinforced concrete column?
A reinforced concrete column is a vertical member made from concrete and steel bars that carries loads from floors and beams down to the foundations. The concrete resists compression and provides fire protection, while the steel bars resist tension and bending.
Do I need a structural engineer to design a reinforced concrete column?
Yes. Columns must be designed by a structural engineer so that axial load, bending, buckling, cover and detailing all comply with UK design codes and Building Regulations. Rules of thumb alone are not enough for Building Control approval.
Which codes do you use for column design?
Most projects are designed to Eurocode 2 with the UK National Annex. Where requested we can also design to BS 8110 so that the calculations match older parts of a scheme or the requirements of a particular warranty provider.
Can you check existing reinforced concrete columns?
In many cases yes. With reasonable information on column size, reinforcement and loading we can assess whether existing columns are adequate and advise if strengthening or further investigation is needed.
How long does reinforced concrete column design take?
Simple column checks for small projects often fit within our usual 24–72 hour turnaround once we have all the information. Larger frames or heavily loaded transfer columns may take longer and will be agreed at quote stage.
Projects where we designed reinforced concrete columns
A few short comments from clients who asked us to design or check their reinforced concrete columns.
Loft and rear extension – Manchester
Columns supporting new steel beams
“SECalcs designed the reinforced concrete columns and beams for our loft and extension. The drawings were clear, the steel fixer had no questions and Building Control approved the calcs straight away.”
Retail unit conversion – Birmingham
New RC frame within existing shell
“We needed new reinforced concrete columns inside an existing building. The engineer coordinated with our architect and gave practical bar details that fitted around services and cladding.”
New build apartments – South East
Multi-storey column design
“Column sizes and reinforcement were optimised so we kept structure slim while staying within code limits. The schedules dropped straight into our drawings which saved time on site.”
Request a structural engineer quote for reinforced concrete columns
Use this form to outline your project. Your enquiry goes straight to an engineer, not a call centre.
Tell us about your reinforced concrete column design
Share a few details so we can review the drawings, confirm the loads and agree a fixed fee for your reinforced concrete column calculations.
This form connects to our central SECalcs email. You will usually hear back from a structural engineer within one working day.
Ready to move your reinforced concrete column design forward?
If you need a reinforced concrete column for an extension, frame or new build and want clear structural calculations, send us a few details and we will confirm the next steps and a fixed fee.
- Head Office: Corwell Lane, Uxbridge, England, UB8 3DE.
- 07359 267907
- info@structuralengineercalcs.com
- Company No: 12653163