Planning a Machinery Shed: Sizing, Doors and Layout for Scottish Farms

Most farmers we talk to have the same story. They built a machinery shed fifteen or twenty years ago. It was big enough then. Now the new tractor only just clears the door, the combine lives outside half the year, and the sprayer is parked in the yard.

Machinery keeps getting bigger. A shed is a long-term decision. So the best advice we can give is: plan for the kit you'll have in ten years, not the kit you've got today. The wider questions for any farm building are in the agricultural steel buildings guide. How the frame itself is put together is in portal frame basics.

Start with what's going in

Before you think about bays and spans, make a list:

• Every machine that will live in the shed
• Its length, width and height, with any folding parts in their stored position
• Whether it needs to go in and out daily, or is stored for the season
• What else needs to fit: workshop space, fuel, spares, a bench, a welfare area

Measure the biggest items, then add room to manoeuvre and walk around them. Tight sheds lead to damaged doors, damaged kit and wasted time.

Width and clear span

A machinery shed works best with as few internal columns as possible. Steel portal frames give clear spans, which means you can park and turn without weaving around posts.

The width you need depends on how you park:

• Nose-in parking off one side needs the building to be deep enough for the longest machine, plus clearance
• Drive-through layouts, with doors at each end, make life easier for trailed kit but need doors on both gables

Think about the turning circle in the yard, too. A shed is only useful if you can get kit into it.

Eaves height and door height

This is the one people regret most. Eaves height (the height at the top of the walls) limits your door height. Door height limits what you can put in.

• Check the height of your tallest kit in the stored position, including cabs, beacons and folded booms
• Allow a sensible margin on top
• Consider what your next tractor, telehandler or combine is likely to be

Raising the eaves at design stage is relatively straightforward. Raising them later is not.

Doors

• Roller shutter doors are common, secure and weathertight. Electric operation is handy for doors used daily.
• Sliding doors are a traditional option and can give very wide openings.
• Open bays are cheapest and fine for some kit, but give less security and protection from wind-driven rain.
• Personnel doors for walking in and out without opening the main doors are worth including.

Door position matters too. Doors on the gable end, on the side, or both? Which way does the prevailing wind come from? On exposed Scottish sites, facing open bays away from the worst weather keeps rain and snow off the kit.

Bays and length

Steel buildings are built in bays, the spacing between frames. The number of bays sets the length. Think about:

• How many machines will be parked side by side
• Whether you want a workshop or store in one or more bays
• Whether you might extend later (designing the end frame for future extension helps)

Keeping kit dry

Machinery is expensive. Condensation dripping off single-skin roof sheets onto electrics and paintwork is a real problem in Scotland's climate. Options include:

• Anti-condensation lining on roof sheets
• Insulated panels on the roof or in a workshop area
• Good ventilation through the building

We've covered this in more detail in our guide to insulated panels vs single-skin cladding.

Daylight

Rooflights or translucent sheets in the roof make a huge difference to working in the shed. Plan them where they're useful, and remember they need to be considered for safety during installation and any future roof access.

Workshop and welfare

If part of the shed will be a workshop:

• An insulated, lined area makes it usable year-round
• Plan power, lighting and possibly water
• A personnel door and window make it a pleasant place to work
• Consider a separate area for fuel, chemicals or oil storage, with the appropriate controls

Planning permission

Some agricultural buildings in Scotland can be built under permitted development with a prior notification to the planning authority. Others need full planning permission. It depends on factors like the size of the holding, the size and location of the building, and its use. Our agricultural building planning guide explains more, but always check with your local council.

Kits vs designed buildings

Agricultural shed kits can suit simpler buildings and farmers with their own team to put them up. For larger sheds, unusual sizes, or exposed sites with high snow and wind loads, a building designed and erected for your site is often the better route.

Cost

Every building is priced individually. Our agricultural shed cost page explains what drives the price. The main factors are size, eaves height, loads for your location, cladding choice, number and type of doors, and rooflights.

FAQ

How big should a machinery shed be?

Measure your current and likely future kit, add room to manoeuvre, and design around that. Most people regret going too small far more than too big.

What eaves height do I need for a modern tractor?

It depends on the tractor and any cab-mounted equipment. Measure your tallest machine and allow a margin above it for the door height you need.

Should I choose roller shutters or open bays?

Roller shutters give security and weather protection. Open bays cost less and suit some uses. Many sheds combine both.

Can a machinery shed be extended later?

Yes, if the design allows for it. Planning the end frame for future bays makes it much easier.

Do I need planning permission for a machinery shed?

Possibly. Some agricultural buildings can use permitted development with prior notification; others need full permission. Check with your council.

Tell us about your shed, and get a price.