How much does decking cost? Real installed prices

Most decking cost guides quote the price of boards. That is not what decking costs. By the time you add the frame, the joists, the sub-base preparation, the fixings, the fascia, and the labour, the installed price is a different number. This guide gives you the installed figures, the variables that move the price up or down, and the questions worth asking before you accept a quote.

Timber and composite sit at opposite ends of the cost range. Scottish conditions, particularly the combination of frost, persistent damp, and gradient, affect both the build cost and the long-term value of the material you choose.

What drives the cost of decking installation

Size is the first variable, but not in the way most people expect. The cost per m2 falls as the deck gets larger because setup time, access costs, and material waste are spread across more boards. A small deck is relatively expensive per m2; a larger deck is more efficient to build.

The material you choose affects both the upfront price and the time it takes to install. Composite boards need precise expansion gaps and, in most cases, a hidden clip system that is slower to fit than face-fixed timber. The boards cost more per linear metre too. On a like-for-like m2 basis, composite is more expensive than pressure-treated softwood at both the material and the labour stage.

Sub-base condition moves the price significantly. A level garden with decent drainage is a straightforward prep job. A sloped site, waterlogged ground, or a garden that needs concrete footings poured for structural posts adds prep time and material cost before a single board goes down. Many quotes assume a level, well-drained site. If yours is not, establish that upfront.

Access matters more than homeowners expect. Gate width, distance from the road, and whether a machine can get through all affect how long a job takes. A rear garden with no side access means materials are carried by hand. That time lands in the quote.

Fixings type affects both price and the finished result. Face-fixed screws are faster and cheaper. Hidden clip systems take longer to install but leave no visible fixings in the surface. If a quote does not specify which method is being used, ask before you sign anything.

Height adds cost and complexity. A deck over 600mm from ground level needs more structural framing, and once it passes that height, balustrades become a building regulations requirement. A raised deck is a bigger build than a ground-level one, and the framing carries that cost.

Timber decking cost: what to expect

Pressure-treated softwood is the most common decking material in the UK. It is the lowest entry point, and for many gardens it is the right choice.

Pressure-treated softwood is the lowest installed cost of the common decking materials, typically £70 to £130 per m2 installed across the UK. That covers the frame, joists, boards, fixings, and waste clearance, not just the boards themselves. Material-only prices from a merchant sit well below that because they leave out the labour and the frame, which are most of the job. If a quote you receive lands under about £70 per m2, check what it excludes before you compare it against anything else.

With annual treatment, pressure-treated softwood typically lasts 10 to 15 years. Annual maintenance means cleaning the boards, applying a decking oil or stain, and replacing any boards that have split or lifted. It takes around half a day and a modest annual spend on decking oil or stain. That cost compounds over the life of the deck and should factor into how you compare timber against composite.

What a timber quote should include: the frame, joists, decking boards, fixings, and waste clearance. If those items are not listed explicitly, ask the contractor to itemise them. A quote that does not spell these out is not necessarily covering them.

Hardwood decking, oak and iroko being the most common options, sits at a higher price point than softwood and often overlaps with composite. The boards are denser, have better natural resistance to rot, and hold their grain longer. If hardwood is what you have in mind, raise it at the site visit so the specification and cost can be worked out for your project.

Timber makes sense for lower-budget projects, shorter time horizons, and clients who are comfortable with annual maintenance. If you are looking at a deck you intend to keep for a decade or more, run the numbers on total cost before you decide.

Composite decking cost: the real numbers

Composite boards have a wood-plastic core with a polymer outer cap. They cost more per board than timber, and they take more care to install correctly. The price difference shows up at both the material and the labour stage.

Composite is the higher installed cost of the two, typically £110 to £200 per m2 installed. Where it lands depends on the board: entry-level hollow-core sits at the bottom of that range, solid capped boards and premium brands such as Trex or Millboard at the top. If you are seeing composite quotes that look close to timber prices, check whether the subframe, hidden clip system, fascia boards, and steps are included. Many composite quotes start with the boards and build everything else on top as extras.

The install process is more demanding than timber. Composite boards expand and contract with temperature, so expansion gaps at install are not optional. Hidden clip systems are slower to fit than face screws. Some installations use an aluminium subframe rather than timber joists because aluminium does not move with moisture the way timber does. All of that is reflected in the labour cost.

A mid-size deck of around 25m2 is a common project size. In composite, that lands somewhere between roughly £2,750 and £5,000 installed depending on the board and the site; the same deck in pressure-treated timber runs closer to £1,750 to £3,250. Access and groundwork move both figures, a sloped or waterlogged site that needs footings poured adds cost before the frame goes down.

If you are working through your garden decking ideas and weighing up which material fits your garden, composite suits clients who want no annual maintenance and a finish that holds for ten years or more without retreatment. In Central Scotland, where winters are wet and frost cycles are real, composite holds its appearance longer than pressure-treated softwood. Persistent damp accelerates timber degradation here faster than guides written for the south of England tend to suggest.

MacColl & Stokes handle composite and timber decking installation as a full installed job: subframe, fixings, boards, fascia, and steps where needed. If a quote you receive does not include all of those items, it is not a like-for-like comparison.

The costs that most quotes leave out

Steps are the first thing to go missing from a base quote. A deck that sits 400mm above ground with three step runs is a different job from a level-change deck requiring a full staircase. Each step run has its own cost, and a full staircase can add a meaningful figure to the total. Ask any contractor to break this out as a separate line item.

Balustrades are a building regulations requirement for any deck over 600mm in height. Glass panels cost more than metal, and metal more than timber. The choice affects both the cost per linear metre and the overall appearance of the finished deck, so it is worth deciding early rather than treating it as an add-on.

Waste removal is often excluded from base quotes. Skip hire for timber off-cuts and packaging waste is a separate cost. If a quote does not mention waste disposal, ask where it goes and who pays.

Groundwork is the line that catches people out most often. If the ground needs levelling, drainage improving, or concrete footings pouring for structural posts, that is additional work outside most base quotes. Establish upfront whether groundwork is included or priced separately. Never assume it is in.

Lighting is increasingly expected on a finished deck. If you want integrated lighting, you need an electrician. That sits outside most landscaping contracts and is a separate cost.

Composite vs timber over ten years

The choice between composite and timber is not a headline price question. It is a ten-year total cost question.

Timber costs less upfront. But every year you own it, you spend time and money treating it: a modest annual outlay, usually a tin or two of decking oil or stain, plus occasional board replacements for boards that have split or lifted. Those costs, added up over ten years, close a meaningful portion of the gap between timber and composite upfront prices.

Composite costs more upfront. Beyond an annual clean, the ongoing cost is near zero. No treatment products, no re-staining, no board swaps.

Industry guides put the point at which composite becomes the cheaper option at around five to seven years for a maintained timber deck. In Scottish conditions, where damp and frost accelerate timber wear, it tends to arrive at the sooner end of that.

Scottish conditions push that crossover point earlier than most national guides acknowledge. Frost cycles lift and crack timber boards faster here. High rainfall means decks are wet for much of the year, not just a few months of it. Composite boards are impervious to moisture. Timber is not. If you are planning a deck you intend to keep for a decade or more, it is worth costing composite properly before dismissing it on headline price alone.

For a full picture of the options available, the composite and timber decking service page covers the range MacColl & Stokes work with across Central Scotland.

How MacColl & Stokes approach decking

Scott has watched homeowners accept the lowest decking quote and spend more fixing the problems that followed. The most common failure is a sub-base that was assumed to be level rather than checked, groundwork that was not in scope, or fixings that were face-screwed in areas where hidden clips were quoted. The visible difference shows immediately. The structural difference takes a winter or two to appear.

MacColl & Stokes price a full installed job: subframe, fixings, boards, fascia, steps where needed, and waste clearance. If the groundwork is genuinely straightforward, it is included. If it is not, you find out before work starts, not halfway through.

The work covers Bearsden, Newton Mearns, Bothwell, Edinburgh, Stirling, and the surrounding areas. If you want to understand what an installed job looks like for your specific garden, a site visit is the right starting point. Prices vary by site too much for a meaningful number to come from a phone call alone.

Frequently asked questions

How much does 25m2 of decking cost?

A 25m2 deck is a typical mid-size residential job. In pressure-treated timber, expect roughly £1,750 to £3,250 installed; in composite, roughly £2,750 to £5,000. Both assume reasonable access and a level site, with groundwork and steps priced separately. The accurate figure for your garden comes from a site visit.

Is composite decking more expensive than timber to install?

Yes, both in materials and in labour. Composite runs roughly £110 to £200 per m2 installed against about £70 to £130 for pressure-treated softwood. Composite boards need precise expansion gaps and typically use hidden clip systems that take longer to fit than face-fixed timber screws, so the labour is higher too, on top of the material cost difference per board.

What is decking cost per m2 in the UK?

Installed cost varies by material, deck height, access, and sub-base condition. As a UK guide, pressure-treated softwood runs roughly £70 to £130 per m2 installed and composite roughly £110 to £200. Material-only prices from a builder's merchant give no indication of what a job costs once it is installed. They are two different figures, and the real number for your deck comes from a site visit.

Is decking cheaper than a patio?

At entry level, generally yes. Pressure-treated timber decking typically costs less per m2 installed than porcelain paving or a poured concrete base. Composite decking overlaps with mid-range stone paving at the upper end of both materials. For a full comparison before you decide, it is worth reading about how much a patio costs alongside this guide.