Building components · Frame Members
Column
Explains the column as the vertical load path in a frame, distinct from walls that carry load along their length.
Educational reference entry. What this element has to do, and whether any particular arrangement of it is adequate, depends on the whole assembly, the loading, the exposure, local requirements, the manufacturer's instructions and qualified professional design.
Overview
What a column is
A column is a vertical member whose job is to carry load downward. It gathers load from the beams, slabs or roof members it supports and delivers it as a concentrated force to whatever is beneath — another column, a transfer element, or a foundation.
Its defining property is that load arrives at points rather than along a line. That is what separates a framed building from a loadbearing-wall building, and it is why framed buildings can have open walls: the walls are not carrying anything.
Boundaries
How it differs from nearby elements
The distinctions that keep this entry from being a restatement of its neighbours.
- It is not a loadbearing wall. A wall carries load continuously along its length; a column carries it at a point, and the foundations beneath the two are different in kind.
- It is not a pile shaft. Both are slender vertical members, but a pile is in ground whose properties were investigated, while a column is in air and is restrained by the structure around it.
- It is not a mullion. A mullion carries the weight of glazing and wind load on a facade; a column carries the building.
Terminology
Common names and aliases
These names describe the same element. The library keeps one entry per component so that a trade term or a regional name never becomes a second, thinner page.
- columns
- post
- stanchion
- structural upright
Dependencies
What it depends on
What has to be right elsewhere for this element to do its job.
- What restrains it laterally along its height, since an unrestrained vertical member behaves very differently from a restrained one.
- The connections at each end, which determine both how load enters and leaves it and how it is held in position.
- What it bears on, and whether that support settles differently from adjacent supports.
- Whether it needs protection — from fire, from impact, or from corrosion — that its material does not provide on its own.
Considerations
Topics that genuinely apply here
Subjects worth discussing about this element. These are discussion topics, never measured values, ratings or performance claims.
A column commonly supports a large area, so what happens to it in a fire is a different question from what happens to a small member. Protection requirements are a matter for design and regulation.
Load arriving at a point has to be delivered into whatever is below, and the transfer element is usually where the design attention sits.
Adjacent supports settling by different amounts affects the structure spanning between them, which is why column foundations are considered together rather than individually.
Column positions constrain everything else — services, partitions and openings all have to work around them.
Materials
Commonly formed from
Material families this element is commonly realised in. This states common practice only — it is not a statement that any of these materials suits this component in a particular building, which depends on the whole assembly and on qualified review.
Assemblies
Building systems this element is met in
The role this component fills inside each assembly. A role describes what the element does there — it is not a statement that this component suits that system in any particular building.
Junctions
Interfaces this element takes part in
Junctions where the condition between this element and another governs how the construction behaves. These name the junction and the subjects it raises; they are not details, arrangements or approved ways of building.
Beam End to Column
Where a beam meets a column, and where the connection's stiffness determines how the whole frame behaves.
Raises: Structural transfer · Fire continuity · Buildability · Movement
Where it is met
Application contexts
Building contexts where this element is commonly encountered. Association is not recommendation: appearing here does not mean the component suits every instance of that context, or any particular one.
- Superstructure
Clarifications
Commonly misunderstood
- That a column in a frame can be removed if a wall is added nearby. The load path is through the column, and changing it is structural alteration.
- That column and post mean different things structurally. The words differ by tradition and material rather than by function.
Conversations
Questions for qualified professionals
Questions worth asking someone with the project in front of them. This page cannot answer them.
- What load does this column carry, and where does that load go beneath it?
- What restrains the column laterally, and does any proposed work remove that restraint?
- What fire protection applies to this column, and is it intact?
- Are the foundations under adjacent columns expected to settle similarly?
Go deeper
Related Build Design Hub guides
Planning guidance behind the decisions this element involves.
Preparation
Related planning checklists
Owner-side preparation before the conversation where this element comes up.
What this entry does not do
- No section, height, capacity, spacing, fire rating or protection specification is stated here.
- Any work that affects a column is structural alteration and requires qualified design.
Structural Frame Members
The columns, beams, joists, rafters, plates and bracing that make up a load-carrying frame, identified by the position each occupies.
Browse all frame members entries →