Decking looks like a ready-made floor for a garden bar, and for a light counter it often is. For a heavy building, a full fridge or a sleeper bar, the deck may not be the base it appears to be.
What decking is designed for
A typical garden deck is built for people, furniture and plant pots. Its joists, posts and footings were sized for that. A bar adds concentrated loads: a full fridge, kegs, a stack of sleepers or a building with its own floor and roof. Before you add weight, find out how the deck was built.
Check the structure
- Look underneath for the joist size, spacing and condition.
- Check posts and footings for rot or movement.
- Look for soft or springy boards.
- Check fixings for rust.
If you didn't build it and can't see underneath, ask a carpenter to look.
Light counters
A framed timber counter or a bar cart usually sits happily on a sound deck. Spread the weight with a frame that bears on several joists, and fix it down so it can't tip.
Heavy items and buildings
A bar shed, log cabin or sleeper counter usually needs its own base. Many building makers specify a particular base and may not accept decking. See base options. One approach is to build the deck around a separate base so the building stands on its own foundation.
Water and rot
Decking boards hold water under anything placed on them. Leave gaps for air, raise counters on feet or bearers and avoid trapping leaves. Water spilled behind the bar runs between boards, so keep the area below clean and ventilated.
Slippery boards
Spilt drinks and algae make decking slippery. Clean the deck regularly and choose grooved or anti-slip boards for the area around the bar. See flooring.
Raised decks and planning
In England, the Planning Portal explains that decking and other platforms above a certain height need planning permission, and a raised deck can also affect neighbours' privacy. Check before raising a deck to suit a bar.
Power across decking
Cables shouldn't be run loose under or over decking. Plan routes with the electrician. See power.
Before you carry the first crate onto the deck, get underneath it with a torch. Ten minutes looking at joists is the cheapest structural survey you will ever do.
Quick answers
Can I put a bar shed on decking?
Only if the deck is designed for the load and the building maker accepts it. Many specify a separate base.
Will a garden bar damage my decking?
It can trap water and cause rot under it. Raise it on bearers, leave airflow and keep the area clean.
Sources
Primary guidance checked 10 November 2026.