Barn construction: what to know

What the job involves, what changes the price, and what to ask a pro.

What barn construction is

Barn construction builds an agricultural building with posts or framing, a roof, siding, doors and floors suited to livestock, equipment, hay or a workshop. The base is usually poured or compacted, and the design has to handle heavy loads, wind and snow, plus the access and clearance a working farm needs.

Signs you need it

  • You need covered space for livestock, hay, feed or machinery that the current structure cannot hold
  • Your existing barn has rot in the posts, a sagging roof or a leaking wall that repairs cannot fix
  • You want a workshop or equipment shed large enough for tractors, trailers or a truck
  • You are adding animal housing and need stalls, ventilation, a concrete alley and a drainage plan
  • Your property has a new building site that needs a foundation, posts and a roof built to the local snow and wind loads

What the pro does

  • The builder checks the site for access, drainage, soil and the setbacks, and marks the layout
  • They set the posts in holes or on piers, or they pour footings and the base for the floor
  • They frame the girts, the trusses or the rafters, and brace the structure so it resists wind
  • They install the roof and the siding, then the doors, the windows and the vents the building needs
  • They lay the floors, such as concrete or compacted gravel with a stone surface, sized for the traffic and the animals or equipment
  • They check the structure for plumb and square, and confirm the doors and the vents work before the final walk-through

What changes the price

Every job is different, so we do not publish prices. These are the things that move the quote up or down.

  • Building size, the number of bays and the wall and roof height
  • Post or frame type, such as treated posts, steel framing or engineered timber, and the spacing between them
  • Foundation type, including poured footings, piers or a compacted base, and any excavation needed
  • Floor type, such as concrete, gravel or a specialty surface for animals or machinery
  • Door count and size, since wide equipment doors need heavier framing
  • Ventilation, lighting, water and electrical service for animals or a workshop
  • Site access for delivery of materials and the equipment needed to set the posts

What a written quote should spell out

  • Building size, post or frame spacing and the design loads it is built to carry
  • Footing or base type, and the excavation and compaction included
  • Roof and siding materials, with the fastener and the bracing scope
  • Door and vent scope, including sizes, tracks and the animal or equipment access
  • Floor material and thickness, and any drainage work included
  • Permit and engineering responsibility, and who stamps any structural drawings

Questions to ask before you hire

  • What design loads is the barn built to, including snow and wind for my area?
  • Will the structure be stamped by an engineer, and who pays for that?
  • How will the posts or footings be set, and how deep will they go for my soil?
  • Does the floor suit the animals or the machinery I plan to use, and how will it drain?
  • What door sizes do you recommend for my equipment, and how are they braced?
  • Who pulls the permit, and what inspections are required for this building?
  • What warranty covers the posts, the roof and the siding?

Red flags

  • They set posts or footings without checking the soil or the frost depth for the site
  • They will not say what snow or wind loads the building is designed for
  • They use undersized posts or framing for the span and the door width
  • They do not plan drainage, so water collects at the posts or on the floor

What you can do yourself

You can clear the site, mark the footprint, gather the survey and the building plan, and decide the layout of stalls, doors and storage. Do not set posts, pour footings or frame the roof yourself, because the building depends on correct depth, spacing and bracing to resist wind and snow. Use a licensed builder, and an engineer where the design requires it.

Licenses and permits

Barns and agricultural buildings are often exempt from some permit rules, but many areas still require a building permit, and larger or occupied structures usually do. Electrical and plumbing work must be done by licensed trades in most places. Check with your state or local licensing agency and your local building department for the agricultural exemption and the permit rules that apply.

Barn construction questions

How deep do the posts need to be?

The depth depends on the frost line, the soil and the load on the building. Ask the builder how they determined the depth and whether an engineer checked the design for your site.

What floor works best in a barn with animals?

A concrete floor is easier to clean and disinfect, while a compacted gravel base with a stone surface drains well and suits some animals and equipment. Tell the builder the animals and the machinery so the floor and the drainage match the use.

Do I need an engineer for a barn?

Many barns require an engineered design for the loads, especially with large spans, heavy doors or heavy snow. Ask the local building department whether an engineer's stamp is required before the building is built.

About this guide

This national guide is written and checked by infinibell. Rules and conditions differ by place, so local pros are credited on guides for the cities they serve, not on national ones.

Edit history

How it works

  1. 1. Describe the job

    Pick the service, add your ZIP and a sentence about what is going on.

  2. 2. Pick the pros you want

    See screened pros who serve your ZIP and choose who you want to hear from.

  3. 3. They reach out

    They contact you the way you chose: phone, email or in-app messages.

More construction and design guides

Find a pro near you

Find a pro

About this guide

Request barn construction