What to Know Before Adding a Pergola to Your Garden

A garden pergola creates a defined outdoor space for seating or dining. A timber pergola typically costs about £1,000 to £3,500 supplied and fitted in 2026, while aluminium designs run from £2,500 to £10,000 or more. Whatever the material, the build must be founded and fixed properly to withstand wind and weather. This guide explains the materials, costs, footings and checks to make before you ask a landscaper for quotes.

What does a pergola do for a garden?

A pergola is built from upright posts carrying crossbeams and lateral timbers that form a canopy over an eating area or walkway. It provides shade in the summer and gives a sense of enclosure without blocking the breeze. If your garden is overlooked by neighbouring windows, a pergola adds privacy from above while keeping the sides open.

Landscapers use them to link different parts of the garden or to create a focal point at the end of a path. A well-built structure breaks up the flat lines of a garden and gives you a reason to walk down to the lawn. They also provide a sturdy support for climbing plants to grow up and over the frame.

If you are planning a full garden design, a garden designer produces the plan, a landscaper or landscape contractor builds it, and a gardener maintains it. Working with a designer helps ensure a large timber or metal frame sits in proportion with the rest of the hard landscaping. The professional body for designers is the Society of Garden and Landscape Designers (SGLD).

Should you choose timber or aluminium?

The material you choose decides how much upkeep the structure needs and how long it survives the UK weather. Treated softwood timber is the cheapest option but requires re-staining or re-oiling every two to three years. If maintained well, a treated softwood frame lasts 15 to 20 years.

The Royal Horticultural Society recommends more durable timbers such as larch, Douglas fir or oak for a longer life. Pine tends to rot more quickly, especially if the base sits in damp soil. Timber frames suit traditional gardens and offer a natural surface for climbers to grip.

For modern designs, aluminium does not rot or need staining and holds its finish for 15 to 20 years. Aluminium frames cost more upfront but require almost no maintenance beyond an occasional wash.

Open, covered and louvred roof options

The roof design dictates how you can use the space underneath. A traditional open top relies on timber crossbeams and the foliage of climbing plants to dapple the sunlight. It offers little protection from the rain but feels light and airy.

A fixed covered roof keeps the rain off the seating area beneath. This setup requires a fall, which is the slight slope that sheds water away rather than letting it pool on top.

The rain that runs off a covered roof has to go somewhere, so ask how the installer will direct it to soil, a lawn or proper drainage rather than towards your house.

The most expensive pergola roof ideas use an adjustable louvred system, sometimes called a bioclimatic roof. These aluminium structures have motorised or manual slats that you can open to let the sun in or close tight when it rains.

How much does a pergola cost?

Landscapers price per project after a site visit. The main cost drivers are the area, groundwork, levels, access, waste removal, drainage and materials. Everything carried through the house costs more, and London and the South East cost more than other areas.

You can expect to pay between £150 and £300 per square metre for timber, and £350 to £600 per square metre for aluminium. A standard three by four metre timber frame takes two fitters about one and a half days to build. Fitters charge about £180 to £300 per day, and labour-only builds cost £400 to £1,200. Landscape gardeners generally charge £30 to £60 per hour.

The table below shows typical supply and fit costs for different materials and extras.

These figures are typical published prices for 2026, and local quotes will differ. Design fees are usually separate, larger jobs are paid in stages, and you should always check whether VAT is included in your quote.

What size and height work best?

Getting the proportions right ensures the structure looks balanced and functions well. The uprights should be around 2.7 metres tall from ground level. This height allows climbing plants to trail down from the crossbeams without impeding passage for people walking underneath.

The width of the frame should be roughly the same as its height. Posts are usually spaced anywhere from 0.9 to 3.7 metres apart, depending on the weight of the roof and the look you want. A pergola post must be thick enough to carry the heavy crossbeams and withstand strong winds, meaning uprights should measure at least five by five centimetres, and ideally eight by eight centimetres for a sturdy build.

If you are building near mature trees, be aware of strict rules. A Tree Preservation Order makes it an offence to cut down, lop, uproot or damage a protected tree without the council's consent. Work on trees in a conservation area normally needs six weeks' notice to the council.

How footings and fixings prevent rot

The groundwork nobody sees is where corners get cut, and a poor foundation means the frame will sink or rot. If you sink timber directly into wet soil, it will decay quickly. The base of every post must be treated with preservative before it goes into the ground.

A reliable footing method involves putting five to seven centimetres of coarse gravel at the bottom of the hole for drainage. The post is then set inside a large drainpipe with the rim positioned just above soil level, keeping the timber away from damp earth.

If the pergola is going on an existing patio, the posts are often fixed with metal post bases, so the paving and what lies beneath it need to be solid enough to hold them. Slabs laid on dabs of mortar instead of a full bed are a weak point, as is a thin sub-base, the layer of compacted crushed stone under paving, so ask how the bases will be fixed.

If the pergola is going on decking, ask whether the posts will have their own footings or be fixed to the deck frame, and how the frame will carry the extra load.

Which climbing plants suit a pergola?

Soft landscaping brings the timber frame to life, and climbers soften the hard lines of the wood while providing natural shade. Rambling roses, clematis, honeysuckles, wisteria and jasmine are all well suited to growing up and over the crossbeams.

As these climbers mature, they often leave bare lower stems near the ground. You can cover these bare sections by spiralling new shoots around the post as they grow. Cutting back the main stems in early spring also helps encourage thicker growth lower down.

Do you need planning permission for a pergola?

The rules around building garden structures depend on your property. Under the Planning Portal guidance for England, permitted development covers sheds, greenhouses, garages and other ancillary garden buildings and enclosures.

These permitted development rights come with conditions. You cannot build forward of the principal elevation of your house, and no more than half the land around the original house can be covered by additions. There are also rules against verandas, balconies or raised platforms over 30 centimetres high. A building or enclosure within two metres of a boundary has a maximum height limit of 2.5 metres.

Pergolas are not named in this official guidance, so you should check with your local council first if you plan to put a pergola on a raised platform over 30 centimetres, fix it to your house, or build it in front of the house. You must also check if you want a large covered structure close to a boundary, if you live in a listed building, or if your home is in a conservation area or other designated land.

These planning rights apply to houses, not flats or maisonettes. If you live in a flat or outside England, check with your council.

Rules for safe outdoor electrics

Adding outdoor heaters or string lights makes the space usable into the evening. Lighting and heating should be installed by a qualified electrician.

Electrical Safety First advises using a residual current device (RCD) with all outdoor electrical equipment. It protects you from electric shocks if something is faulty. You should never use electrical equipment outdoors until it is dry, and you should never attempt to wire outdoor lighting or heating yourself.

How to choose a trustworthy landscaper

Because landscaping is not a licensed trade, vetted membership and evidence of past work matter. The British Association of Landscape Industries (BALI) says its Accredited members are vetted on workmanship, skill and health and safety. The Association of Professional Landscapers (APL) says members are assessed, regularly inspected and TrustMark accredited.

TrustMark is the government-endorsed quality scheme. Membership of these bodies is a good sign, not a guarantee. Any trader who carries waste must be a registered waste carrier, and the register is public.

Watch out for these common warning signs of poor landscaping work:

• Doorstep callers offering cheap paving or leftover materials from another job.
• Cash deals with no written specification for the materials or the groundwork.
• Thin or missing sub-base that causes heavy structures to sink into the ground.
• No fall on a solid roof so rainwater pools or runs towards your house.

Consumer rights and getting quotes

Under the Consumer Rights Act 2015, any work must be done with reasonable care and skill. If the workmanship falls short, the customer can ask for it to be put right or seek a partial or full refund. To protect yourself from cowboy builders, Citizens Advice suggests getting written quotes from at least three different traders.

A quote is a fixed price, while an estimate is a rough guess that can end up higher. Ask for two to three recent references and check their insurance documents. You might be able to cancel within 14 days of agreeing a written contract or telling the trader to go ahead.

A detailed written quote should clearly state the following:

• The exact named materials and how any timber is treated.
• The excavation depth for the footings and the post bases.
• Any guarantee, and who will install any lighting or heating.
• The drainage plan for the roof and the footings.
• Confirmation that waste removal is included in the price.

Common questions

Do I need a landscape designer or a landscaper?

A garden designer produces the plan, a landscaper or landscape contractor builds it, and a gardener maintains it. If you are just adding a simple frame, a landscaper can manage the job, but a designer is helpful if you are reshaping the whole garden.

How long does a timber frame last?

Treated softwood lasts 15 to 20 years if it is maintained and kept free from rot at the base. You will need to clean it and apply a new coat of stain or oil every two to three years to keep the wood protected from the weather.

Does a covered roof need drainage?

Yes, any fixed impermeable roof needs a slight slope, called a fall, to shed rainwater. Without a fall, water can pool on top of the sheets, which can lead to leaks.

Can I attach a pergola to my house?

Fixing a structure to your house alters the way it looks and can change how planning rules apply. You should speak to your local council before attaching a frame to an exterior wall, as it might no longer fall under standard permitted development for outbuildings.

Next steps before you book

Take these steps before you agree to any landscaping work:

• Decide on the size, material and roof style you want before contacting tradespeople.
• Check the public register to ensure the trader is a registered waste carrier.
• Get written quotes from at least three different traders to compare prices.
• Ask for a written contract covering timings, materials, clean up and payment terms.
• Check that the quote states the exact timber, footing depths and drainage plans.
• Keep any deposit to 25 per cent at most and always pay by card rather than cash.
• Ask who is supplying the qualified electrician for any lighting or heating.

A professional landscaper will visit your garden to measure up and check the ground before giving a final price. When you are ready to start planning your new outdoor space, find a landscaper near you to request a site visit and compare written quotes.