Heavy Duty Bespoke Metal Pergola

A garden centre pergola is an aluminium kit designed to be carried by two people and assembled with an Allen key. Ours is a steel structure, welded and galvanised, designed around your garden and bolted down properly. They are not really the same product and they should not be compared on price.

We design, make, deliver and install bespoke metal pergolas across the UK, in whatever size, section and colour the job needs. Freestanding or fixed to the house, open to the sky or roofed in glass, over a patio, a hot tub, a seating area or a driveway.

What you actually get

• Structure: Welded steel, sized for the span rather than for the packaging
• Finish: Hot dip galvanised as standard, then polyester powder coated in any RAL colour
• Form: Freestanding, wall fixed, or built around an existing feature such as a tree
• Roof options: Open, toughened glass, or polycarbonate
• Extras: Stainless wires for climbing plants, brackets for egg chairs and swings, integrated guttering, hanging basket supports, lighting provision
• Standard: Fabricated to BS EN 1090-2
• Scope: Survey, drawings for approval, fabrication, delivery and installation
• Supply only: Available if you have your own installer

Why galvanised and powder coated, rather than just painted

Powder coat on bare steel looks identical to powder coat on galvanised steel on the day it is installed. The difference shows up in about five years, at the first chip.

Paint or powder on bare steel is a barrier, and a barrier only works while it is unbroken. Chip it with a strimmer, a ladder or a garden chair and the steel underneath starts to rust, the rust creeps under the coating, and it lifts from the inside. Galvanising is not a barrier, it is a sacrificial layer bonded into the surface of the steel, and it carries on protecting the exposed metal at a chip instead of failing at it.

So the sequence is galvanise first, powder coat second. You get the colour you want and the protection you cannot see, and a scratch stays a scratch rather than becoming a repair. It costs more than painting and it is the reason we do not offer painted steel outdoors.

The foundations are most of the engineering

A pergola is a large flat surface held up in the air, which makes it a sail. The load that matters is almost never the weight of the structure or of the planting on it, it is wind trying to lift and rack the whole thing.

That is why what happens below ground decides whether a pergola is any good. Posts want proper concrete foundations sized for the structure, or a designed bolt down connection into a slab that is actually thick enough to take it. Bolting a substantial steel frame to 50mm of decorative paving is the single most common way a good pergola fails, and it usually fails in the first serious gale.

We survey before we quote so we know what we are fixing into. If the base is not suitable we will say so and tell you what needs doing, which is occasionally an unwelcome conversation and always cheaper than the alternative.

Glass, polycarbonate, or nothing at all

An open pergola defines a space and carries planting. It does not keep you dry, and that is worth being clear about before you spend the money.

If you want to sit out in British weather you want a roof, and then you are choosing between glass and polycarbonate. Toughened glass looks better, stays looking better, is quieter in rain and is heavier, which means the structure under it has to be designed for it from the start rather than upgraded later. Polycarbonate is lighter and cheaper, and it is noticeably louder in heavy rain. Both need a fall and both need somewhere for the water to go, which is why guttering is worth adding at the time rather than regretting later.

If a roof is the main thing you are after rather than the structure, look at our glass canopies instead, which are designed around the covering rather than around the frame.

Built around what is already there

The advantage of making these one at a time is that the awkward garden is not a problem, it is the reason to call us. Sloping ground, an existing wall to pick up on, a patio that is not square, a level change, a manhole in the wrong place, or a tree you want to keep.

We built one around a mature tree in Sheffield, which meant setting the frame out to clear the trunk and leaving the canopy room to move. A kit cannot do that. Neither can a kit follow a curve, cantilever over a hot tub, or match a section size you already have elsewhere in the garden.

How far can it span?

Further than most people expect, and the honest answer is that it depends on the section, the covering and the exposure of the site.

The trade off is simple enough to explain. Fewer posts means a longer clear span, which means deeper or heavier sections overhead and bigger foundations. More posts means lighter, more slender steelwork. Neither is right or wrong. If the point of the structure is an uninterrupted view across a terrace, spend the money on the span. If the point is to carry wisteria over a path, do not.

Tell us the opening you want to clear and what you want on top, and we will tell you what section that takes before you commit to anything.

Frequently asked questions

How much does a bespoke metal pergola cost?

There is no list price because there is no standard size. Cost is driven by the footprint, the clear span, the roof covering and the groundwork. Send dimensions and a photograph of the space and we will price it properly rather than give you a figure that changes later.

Do I need planning permission for a pergola?

Usually not, but check rather than assume. An open pergola in a rear garden is normally permitted development in England, subject to height limits and the usual conditions. It is more likely to need consent if the property is listed, in a conservation area, or if the structure is tall, close to a boundary, or forward of the principal elevation. Your local planning authority will confirm in writing and it costs nothing to ask.

Can you match a colour I already have?

Yes. Powder coating is available in any RAL colour at no extra cost over the standard finish, so a pergola can be matched to existing windows, a balustrade, a set of gates or a garden room. Send us the RAL number if you have it, or a photograph if you do not.

Can climbing plants be trained up it?

That is what the stainless wire option is for. Tensioned wires run between the posts and across the top so plants have something to grip that is not the powder coat, and so that pruning does not mean unwinding a wisteria from a hot structure. Fitting them at the time is much easier than retrofitting.

Do you install, or is it supply only?

Both. Supply and install is the normal route and it is what we recommend, because the setting out and the fixings are where these succeed or fail. Supply only is available if you have your own groundworker or landscaper, and we will provide the drawings and the fixing detail so they know what they are working to.

How long does it take?

From approved drawings, most pergolas are made and fitted within a few weeks, depending on the galvanising and powder coating queue and on whether groundwork is needed first. We will give you a realistic date at the quote stage rather than an optimistic one.

Explore more

Projects

• Bespoke steel garden pergola built around a tree, Sheffield
• Stainless steel arches and water rills for an RHS show garden
• All our bespoke projects

Related products

• Glass canopies
• Stainless steel and glass balustrade, System 1

Get a price

Send the size of the area you want covered, a photograph of the space, and anything you already know about what it is fixing into. We will come back with a proper price and a drawing. Email sales@diometonline.co.uk or call 0114 243 9009.