Do You Need a Base for a Pergola? UK Guide (2026)

Yes, a pergola needs a base, but not always a concrete one. A freestanding pergola has to be anchored to something solid and level so it stays square and does not lift or lean in the wind. In the UK you have four practical options: concrete footings, ground screws, bolt-down feet on an existing hard surface, or an integrated decking base that comes ready-built with the kit. The right choice depends on your ground, whether you are adding a roof, and how much digging you want to do. This guide walks through each one so you can pick with confidence.

In this article

• Do you actually need a base for a pergola?
• What are the base options, and how do they compare?
• What is an integrated decking base?
• How deep should pergola footings be in the UK?
• Can you put a pergola on existing decking or a patio?
• FAQ

Do you actually need a base for a pergola?

A pergola is a tall, relatively lightweight structure with a large surface area, which makes it far more sensitive to wind than its weight suggests. Without a proper base the posts can shift, the frame can rack out of square, and a gust can lift or topple the whole thing. So the short answer is yes: every freestanding pergola needs to be fixed to a stable, level foundation.

How substantial that base needs to be depends on one thing more than any other: whether you are adding a solid roof. An open-rafter timber pergola catches less wind than one fitted with a polycarbonate roof kit, which acts like a sail. As a rule, if you are adding a roof you should fix the pergola down properly, either by concreting the posts into the ground or using bolt-down feet onto a hard surface. An open pergola on a level, well-drained spot has more flexibility.

What are the base options, and how do they compare?

There are four foundations that cover almost every UK garden. Concrete footings are the strongest and the standard for exposed sites. Ground screws are the fast, no-cure alternative. Bolt-down feet suit an existing patio or slab. An integrated decking base arrives ready-built as part of the kit. Here is how they stack up.

Base type	Best for	Effort	Wind resistance
Concrete footings	Grass or soil, exposed and windy sites, roofed pergolas	High (dig, pour, cure)	Excellent
Ground screws	Fast installs, minimal digging, rocky or awkward ground	Low (no curing, build same day)	Good
Bolt-down feet	Existing patio, concrete or paved hardstanding	Low (drill and bolt)	Good on solid slab
Integrated decking base	A complete, level outdoor room with no separate groundwork	Included with the kit	Good, fix down if roofed

Gravel footings and pre-cast concrete blocks are two more no-dig options worth knowing about. Gravel-filled holes drain well and suit lighter, open structures, while pre-cast blocks cradle each post and are handy for renters or temporary builds on level ground. For a full timber pergola in British weather, though, most people land on one of the four in the table above.

What is an integrated decking base?

An integrated decking base is a timber deck that is designed and supplied as part of the pergola, so the posts sit on a solid, level platform from the moment you build it. It removes the single most off-putting job in a pergola project: preparing a foundation. Instead of hiring a mixer, digging footings and waiting days for concrete to cure, you assemble the deck and the frame together as one kit.

Our freestanding pergolas with decking are made from pressure-treated Northern European redwood and use a precision notched design, so the parts locate cleanly and assembly is straightforward. The deck also lifts the whole structure into a finished, seamless look rather than posts poking out of a lawn. If you add a polycarbonate roof kit, a discreet 5-degree pitch is built in for rainwater run-off, and we recommend fixing the pergola down (concrete or bolt-down feet) once a roof is on, because the roof adds wind load.

How deep should pergola footings be in the UK?

If you are setting posts in concrete, dig each footing at least 60cm deep. That takes the base below the typical UK frost line, so the ground freezing and thawing over winter cannot heave the posts. Add a layer of gravel at the bottom of each hole for drainage, then pour concrete around the post. Soft, wet or loose soil calls for deeper, wider footings, while stony or rocky ground can make digging hard enough that ground screws become the easier route.

Ground screws avoid the wait entirely. They are large spiral anchors driven into the ground with no excavation and no curing time, so you can build the same day. They cause minimal disruption to a lawn, which suits gardens where you would rather not carve up the turf, though on the most exposed sites concrete still gives the best wind resistance.

Can you put a pergola on existing decking or a patio?

On a solid patio, concrete slab or well-laid paving, yes. Bolt-down feet let you anchor the posts straight onto the hard surface, which is quick and avoids digging. Just check the slab is thick and sound enough to hold an anchor bolt.

Existing timber decking is different. A standard decking subframe is not built to carry the weight and wind load of a full pergola, and fixing posts directly to deck boards without serious reinforcement is not recommended. The safest DIY route is to set the posts in their own concrete footings just outside or through the deck, so the pergola stands on its own foundation rather than leaning on the deck structure. If you want the timber-deck look without that problem, a pergola with an integrated, purpose-built decking base sidesteps it entirely, because the deck and frame are engineered to work together.

Frequently asked questions

Does a pergola need concrete footings?

Not always. Concrete footings are the strongest option and the best choice for exposed sites or any pergola with a roof. On a solid patio you can use bolt-down feet instead, ground screws work where you want no digging, and a pergola with an integrated decking base provides its own level foundation.

Can a pergola be freestanding without being fixed down?

A heavy open-rafter pergola on level, firm ground can stand under its own weight in a sheltered spot, but it is safer to anchor it. Any pergola fitted with a roof should always be fixed down, either concreted in or bolted to a hard surface, because the roof greatly increases wind load.

How deep should pergola posts go?

For concrete footings in the UK, dig at least 60cm deep so the base sits below the frost line. Add gravel for drainage and pour concrete around each post. Soft or waterlogged soil needs deeper, wider footings.

What is the easiest pergola base to install?

An integrated decking base is the easiest, because it comes as part of the kit and needs no separate groundwork. Among traditional foundations, bolt-down feet on an existing patio and ground screws are the quickest, since neither requires concrete to cure.

Can you put a pergola on an existing deck?

Only with caution. A normal decking subframe is not designed to carry a pergola, so posts should be set in their own footings rather than fixed to the deck boards. A pergola supplied with its own purpose-built decking base avoids the issue completely.