Guide
Agricultural building cost per square metre: why the rate misleads
Updated
Everyone asks for the rate per square metre. It is the wrong question, and the reason two quotes for the same shed can look nothing like each other.
Why one rate cannot price a farm building
A rate per square metre works where the product is standardised. Agricultural buildings are not. The same 400 square metre footprint might be a bare steel shell erected on existing hardcore, or the same shell with a 150mm reinforced power-floated slab, insulated roof sheets, two roller shutters, concrete panel walls to head height and a full drainage scheme. Both are honestly described as a 400 square metre farm building. They are not the same job and they will not carry the same bill.
So when a supplier gives you a rate, the first question is not whether it is a good rate. It is what scope that rate covers. Frame only? Frame and cladding, erected? Or a turnkey building you can drive a telehandler into on handover?
The scopes a farm building quote can mean
- Kit only, delivered
- Frame, purlins, rails and sheets on a lorry. No erection, no groundworks, no slab. The cheapest headline number and the least useful for budgeting.
- Supply and erect, shell
- The building standing and clad, on foundations someone else has put in. Still excludes the slab, drainage and usually the doors.
- Turnkey
- Groundworks, foundations, slab, frame, cladding, doors and drainage as one contract with one contractor carrying the interfaces. The highest number and usually the one worth comparing.
What actually moves the number
| Decision | Effect on price |
|---|---|
| Wider clear span | Up. More steel per frame, heavier foundations |
| Higher eaves | Up. More steel, more cladding area, higher wind loads |
| Insulated composite panels instead of single skin | Up, sometimes sharply, but essential for some stores |
| Thicker or reinforced slab, power-floated finish | Up. Slabs for grain and heavy plant are a different product from a general purpose floor |
| Poor or sloping ground | Up. Cut and fill, mass fill and piled or deepened foundations are all site-specific |
| Extra openings and roller shutters | Up, per opening. Doors are almost always an itemised extra |
| Difficult access for lorries and cranes | Up. Erection days and delivery costs both rise |
| Reusing an existing base or hardcore | Down, if a structural engineer confirms it is suitable |
How to compare quotes on a like for like basis
- Write your own scope before you ask for prices. Span, length, eaves height, use, slab or no slab, number and type of doors, drainage. Send the same document to everyone.
- Insist on separate lines for groundworks, foundations, slab, frame, cladding, doors and drainage. A single lump sum hides the exclusions.
- Read the exclusions list first, before the price. That is where the difference between two quotes usually lives.
- Ask who carries ground risk. If the contractor has not dug a trial hole, someone is going to pay for whatever is down there, and it is usually you.
- Ask for the erection programme in working days and what happens if the site is not ready. Standing time is chargeable.
We deliberately do not publish a headline pound per square metre figure for agricultural buildings. Any single number would be wrong for most readers, and the ones you see quoted elsewhere rarely say which scope they cover. Get quotes for your actual building instead: tell us the spec and contractors will price it.