How much decking do I need — and what will it cost?
Enter your deck size. We'll count the boards, joists and screws, and give you an honest 2026 cost range for softwood and composite.
Quick answer: In 2026, paying a pro to fit a softwood (natural wood) deck costs £65–£130 per m². Composite (man-made boards of plastic and wood fibre) costs £85–£160 per m². Both are the materials plus £22–£55 per m² of labour. A typical 15m² softwood deck comes in around £1,100–£1,300 fitted on trade-guide figures, or roughly half that if you build it yourself. You need about 1.9 boards (3.6m long) per m², plus joists (the frame timbers underneath) at 400mm centres.
These figures are planning estimates for a straight-laid rectangular deck on level ground. Diagonal boards, picture-frame borders and steps need 15–20% waste and more joists — always check quantities against your final design before ordering.
💷 Where you can save on this job5 honest saves
Refurb before you rebuild. If the frame is solid (joists firm, no rot where posts meet ground), new boards on the old frame cost roughly 40% of a full rebuild. Lift a corner board and poke the joists with a screwdriver before deciding.
Softwood plus oil is the budget play. Half the upfront cost of composite; the honest trade is a maintenance weekend every year or two. If you'll genuinely never oil it, buy composite; if you enjoy garden jobs, softwood wins on money.
Keep the shape simple. Every corner, curve and level change adds frame, cuts, waste and days. A clean rectangle is the best value shape in decking.
Stay under 300mm. Ground-level decks skip handrails (£40–£80 per metre saved) and stay clear of planning questions. Height is expensive in every direction.
Quote it in autumn. Deck season is March–July; the same build quoted in September–October usually comes in keener.
What to actually buy (and where)
A deck is the boards you see and a frame you never see again — and the frame is where the expensive mistakes hide. The other honest problem is transport: 3.6m boards fit in almost no car, so the buying route matters as much as the shopping list. Where the budget option is a false economy, we say so.
Some links below are affiliate links — we may earn a commission, at no cost to you.
Pressure-treated grooved deck board, 27 x 144mm x 3.6m
£12 per 3.6m board at Wickes (promo, was £18) — about £23/m² at 1.9 boards per m²
The 27 × 144mm board is the sweet spot: stiff enough for standard 400mm joist centres, wide enough to lay fast, treated to Use Class 3 with a 10-year anti-rot guarantee — and at the current promo, barely dearer per m² than 'value' boards. One caveat: promos churn constantly in this category, so run the per-m² sum on the day you buy, not from last week's note.
Need boards this weekend: Wickes and Travis Perkins do free click & collect on 3.6m boards — which fit in almost no car. Roof bars are legal (a 1–2m rear overhang just needs the end made clearly visible) but roof-load limits mean a few boards per trip. B&Q's Hertz vans from £13/hour plus mileage beat five trips — and you hand-pick straight boards.
Building a whole deck — most people: Have it delivered: Wickes from £5 (a whole-deck order usually tips the 375kg limit into £35 Big & Bulky), Travis Perkins free over £150. The catch: someone else picked your boards — check every length for warp while the driver is still there. Going composite? Order free samples first (Cladco, NeoTimber) — screen colours lie.
25m²-plus — quantity earns real discounts: Stop paying rack prices: Travis Perkins' beefier 32 × 144mm board is £11.36 with a free trade account, and local merchants expect a 'project price' call at 50-plus boards — full packs run to about £6.80/board, but a pack is 288 boards. The cost: paying up front, kerb space for a HiAB drop, and covering the stack properly.
Tempted to one-click the whole job?: Genuinely right for the light stuff — screws, joist tape, oil (the 5L Ronseal was £3.50 cheaper on Amazon than Screwfix). Wrong for timber: the best marketplace listing worked out at £16.46 a board against £11 on the Wickes shelf — couriered, sight-unseen, and returns on 3.6m lengths are a fantasy.
🪵 Boards (compare per m², never per board)3 honest picks
Most decks
Pressure-treated grooved deck board, 27 x 144mm x 3.6m£12 per 3.6m board at Wickes (promo, was £18) — about £23/m² at 1.9 boards per m² The 27 × 144mm board is the sweet spot: stiff enough for standard 400mm joist centres, wide enough to lay fast, treated to Use Class 3 with a 10-year anti-rot guarantee — and at the current promo, barely dearer per m² than 'value' boards. One caveat: promos churn constantly in this category, so run the per-m² sum on the day you buy, not from last week's note.Pro deck board at Wickes →
Never oiling again
Composite (WPC) deck board, 145 x 24mm x 3.6m£24 per 3.6m hollow board (~£46/m²) or £29 solid (~£56/m²) at NeoTimber, 25-year residential warranty Composite is the honest pick if you never want to oil or stain again — but 'no maintenance' still means a brush-and-wash once or twice a year, it runs hotter than timber in full sun, and scratches can't be sanded out. Boards-only you pay roughly 1.5–4× softwood. Hollow core is fine for garden foot traffic; go solid for heavy planters or hot-tub traffic, and buy the range's hidden clips with the boards.Classic hollow board at NeoTimber →
Small, light-use decks only
Thinner treated 'value' deck board, 25 x 120mm x 3.6m£11 per 3.6m board at Wickes — about £26/m², because 120mm width needs 2.3 boards per m² Right now this is the false economy: the narrower board needs 2.3 boards per m², so at £11 it works out ~£26/m² — more than the thicker Pro board on promo. It only earns its place on a small, light-use deck with joists at 300mm centres, and only when the per-m² sum actually comes out lower on the day. On standard 400mm centres, 25mm boards feel springy.Standard deck board at Wickes →
🪚 Frame & supports (the part you can never replace)3 honest picks
The wood that matters most
Incised UC4 treated joist, 47 x 150mm x 3.6m£33 per 3.6m length at Wickes (trade C16 is £15 — read on) This is where the false economy hides: £15 trade C16 looks like the same wood, but its treatment is above-ground grade. The incised UC4 joist's deeper 15-year treatment is what stops the one part of the deck you can never replace from rotting. Don't pay extra for C24 unless your span demands it — that buys strength, not rot resistance. Brush every cut end with end-grain preservative.Incised UC4 joist at Wickes →
Sound patio underneath
Adjustable plastic decking pedestals£24.99–£35.99 per 10-pack on Amazon (30–140mm heights); Jouplast 10-packs £39–£46 at Wickes Over a sound existing patio this is genuinely the right buy: no digging, millimetre levelling at £2.50–£4.60 a point, and air moves under the frame so it dries out. Where it fails: bare soil, grass, or loose cracked slabs — pedestals sink and the deck goes wavy. Check the maker's stated load rating and that the height range actually matches your finished deck level.View on Amazon →
Lawn, slope or soft ground
Galvanised steel ground screws, 550–1000mm£21–£27 per screw inc VAT from UK specialists The modern answer where there's no hard base: screws go in in minutes each with no spoil, no concrete and adjustable height, so you build the same day — a weekend saved over digging pad holes. The honest trade-off: at £21–£27 a point they cost roughly double a DIY concrete pad in materials, so on a big deck on decent diggable ground, pads still win if your back is willing.Self-install ground screws at SIPS →
Coated decking screws, 4.5 x 65–75mm£8–£18 per box of 200–500 (ForgeFix 4.5 x 75mm box of 200, £10.28) Plain or bright-zinc woodscrews corrode outdoors and react with tannins in wet treated timber — a permanent black streak round every head, and corroded heads shear off when you later lift a board. Coated screws cost a few pounds more per box; budget ~30–35 per m². On Amazon buy the native brands (ForgeFix, TIMCO) — the Screwfix own-brand box is marked up 65–80% by third-party sellers there.View on Amazon →
Composite boards
Hidden T-clip fasteners with stainless screws£12.89–£13.99 per 100 generic; £28.34 per 100 branded (Cladco) — 100 covers roughly 5–6m² Composite shouldn't be face-screwed — the surface mushrooms round the head and some brands void the warranty. T-clips fix through the side grooves: no visible fixings, every gap even. Generic clips (~£2.50/m²) are genuinely fine when the clip height matches your board's groove — check 6mm vs 7mm before ordering — but if your board's warranty demands own-brand clips, pay the ~£5/m².View on Amazon →
While the frame is still open
Butyl joist tape, 50–65mm wide£15.99 for a 50mm x 20m roll; budget 2–3 rolls for a 15m² frame Frames rot from the top, where every screw hole lets water into the board–joist line that never dries. Butyl tape self-seals round the punctures — check the adhesive line says butyl, as some branded 'joist tapes' are acrylic. Honest caveat: the 25-year claims come from the people selling it, and it's build-time only — you can't retrofit under laid boards. £30–£50 of cheap insurance over UC4 timber, not a substitute for it.View on Amazon →
🖌️ Oil (softwood only — composite skips this)the honest pick
The recurring cost
Ronseal Ultimate Protection Decking Oil, 5L£37.94 per 5L can on Amazon (£41.49 at Screwfix) — covers ~16m² at 2 coats Skipping oil won't rot the deck — the pressure treatment does the structural work — it just greys and roughens, so treat this as a cosmetic running cost: one can, every 1–2 summers. Let new treated timber weather 3–6 months before the first coat. Water-based recoats in 4 hours, making it a one-day job; and ignore 'lasts twice as long' — that's the maker's own weathering claim.View on Amazon →
Some links are affiliate links — we may earn a commission, at no cost to you. Retailers named because we checked their prices in July 2026, not because they paid to be here.
3 Plan what else you need
Pick your stage — each opens Amazon.
Affiliate links — we may earn a commission, at no cost to you.
📅 How the job actually goes4 stages
Setout and ground: Area cleared and levelled, weed membrane down, pads or anchors positioned. Boring and essential.
Frame day: The deck IS the frame. Before any board goes on, check it's level, square (both diagonals should match) and ventilated. Everything after this is cosmetic.
Boards: Laid with 5–8mm gaps, two screws per joist crossing. The satisfying day — a 15m² deck boards out in an afternoon.
Trims and finish: Fascias, steps, and the first oil coat on softwood (plus sealed cut ends). Composite needs nothing — that's what you paid for.
Joist size and centres (400mm standard; 300mm for composite or diagonal)
How the frame meets the ground — anchors or pads, never buried timber
Fixings: proper deck screws or hidden clips, not nails
First finish coat (softwood) and waste removal
Questions that sort pros from cowboys:
What joist centres for these boards?
How do the posts meet the ground?
How will air move under the deck? (No airflow is how decks rot)
What expansion gaps do these boards need?
Walk away if:
600mm joist centres with standard boards — bouncy deck guaranteed
Timber posts concreted straight into soil
Nails anywhere in the answer
No mention of ventilation
Booking: Deck builders book out from March. A 15m² ground-level deck is 1–2 days; raised decks with steps and rails run 3–5.
Sense-check it against real quotes
Our figure is researched, but it is not your garden. Post the job free and local landscapers reply with real prices — the honest way to check the estimate above before you commit.
Free to use. If you get quotes through this link we may earn a commission, at no cost to you.
Never done this before? Start here
Softwood is natural wood that has been treated to slow down rot.
Composite is man-made boards, a mix of plastic and wood fibre, that never need oiling or staining.
Whichever you pick, every deck sits on a hidden frame of timber underneath — and that frame matters more than the boards you walk on.
How we work it out
Standard UK deck boards are 145mm wide. They're laid with a 5mm gap between them so rain can drain through. That means every square metre of deck needs about 6.7 metres of board, end to end — roughly 1.9 of the common 3.6m boards. The boards screw down onto joists (the treated timber beams that make up the frame underneath). Joists go at 400mm centres — that means 400mm from the middle of one joist to the middle of the next — which works out at about 2.5 metres of joist per m² of deck. Each board takes two screws at every joist it crosses.
We add 10% waste — spare material to cover offcuts, the odd bent board and small mistakes. That's the standard allowance when boards run straight across a rectangular deck. Laying boards diagonally, or adding a picture-frame border (a band of boards running round the edge, like a photo frame)? Allow 15–20% instead, and expect extra joists — a border needs its own support underneath.
Prices checked July 2026 against major UK DIY retailers (Wickes, B&Q, Screwfix) and trade cost guides. Rounded ranges, not quotes.
What decking costs in the UK (2026)
Item
Typical range
Softwood deck boards (boards only)
£22–£40 per m²
Softwood materials in full (boards, frame, fixings)
£40–£75 per m²
Composite boards — budget own-brand
£30–£45 per m²
Composite boards — big-name brands (Trex and similar)
£45–£85 per m²
Composite boards — premium (Millboard and similar)
£90–£130 per m²
Labour (professional fit)
£22–£55 per m²
Fitted softwood deck (supply + labour)
£65–£130 per m²
Fitted composite deck (supply + labour)
£85–£160 per m²
Prices checked July 2026; the two fitted rows rechecked 30 July 2026. Each fitted band is the materials row plus the labour row, so the table adds up rather than quoting a separate figure.
Worked examples by deck size
Deck size
Softwood, fitted
Composite, fitted
Small — 15 m² (5 × 3m)
£1,100–£1,300
£2,100–£2,300
Medium — 30 m² (6 × 5m)
£1,800–£2,200
£3,700–£4,100
Large — 60 m² (10 × 6m)
£3,500–£4,400
£7,400–£8,200
The 15m² and 30m² figures come from 2026 trade price guides; the 60m² figure is scaled up from the 30m² range. Building it yourself roughly halves these totals — paying for labour is the biggest single cost.
What moves the price
• Board choice — composite costs roughly twice as much as softwood up front. In return you never stain or oil it, and it lasts 20-plus years.
• Height and steps — a raised deck needs proper posts, more frame and often a handrail. Budget a fair bit more than for a deck sitting at ground level.
• Ground condition — soft ground, a slope, or ground that's been built on before all mean more digging and prep work before the frame goes down.
• Removing an old deck — ripping out a tired deck and getting rid of the waste usually adds a few hundred pounds to a replacement job.
• Pattern — laying boards diagonally, or adding a border round the edge, looks great and costs more: 15–20% waste plus extra joists to support it.
• Where you live — labour in London and the South East typically runs 20–30% higher.
Common questions
How much does decking cost in the UK in 2026?
For a deck fitted by a pro, budget roughly £65–£130 per m² for softwood (natural wood) and £85–£160 per m² for composite (man-made boards of plastic and wood fibre). Those figures cover materials and labour — the materials bands above plus £22–£55 per m² of fitting. A typical 15m² softwood deck comes in around £1,100–£1,300 fitted on trade-guide figures; the same deck in composite is nearer £2,100–£2,300. Building it yourself roughly halves those numbers, because labour is the biggest single cost.
Is composite decking worth the extra money?
Composite boards cost roughly twice as much as softwood up front (£30–£130 per m² for boards alone, depending on brand). In return they never need sanding, staining or oiling — just a wash now and then. Softwood is cheaper and looks natural, but set aside a weekend of upkeep every year or two, and expect it to last 10–15 years against 20–25+ for good composite.
Do I need planning permission for decking?
Usually not. In England you can build decking without asking for planning permission (this is called permitted development) as long as it sits no more than 30cm above the ground, and — added together with sheds and extensions — covers no more than 50% of the garden. The common exceptions are raised decks, listed buildings and conservation areas. If any of those apply to you, check with your local council first.
How many deck boards do I need per square metre?
With standard 145mm-wide boards and a 5mm gap between them for drainage, you need about 6.7 metres of board, end to end, for every square metre of deck. That's roughly 1.9 boards per m² if you buy 3.6m lengths, or 2.8 if you buy 2.4m lengths. Add 10% spare for offcuts and mistakes — or 15–20% if you're laying boards diagonally or adding a picture-frame border (a band of boards running round the edge).
Can I build a deck myself over a weekend?
Yes, if it's small and simple. A ground-level rectangular deck up to about 15m² is a realistic weekend job for a confident DIYer with a circular saw, a drill driver and a spirit level. The frame underneath is what decides whether the deck feels solid — take your time getting it level and square. And always screw the boards down with proper decking screws, never nails.
📋 Where these prices come from40 sources
Every price band on this page traces to a source we checked ourselves, with the date we checked it. Prices move — if one of these looks out of date, tell us and we'll recheck it.
softwood deck boards £8–£18 each; £22–£40/m² boards-onlywickes.co.ukchecked July 2026
GoodHome Lemhi 3.6m board £18, £34.48/m²diy.comchecked July 2026
composite tiers £30–£130/m² supply-onlyultradecking.co.ukchecked July 2026
labour £22–£55/m², day rate £200–£340myjobquote.co.ukchecked July 2026
installed softwood £70–£90/m², composite £90–£110/m²checkatrade.comchecked July 2026
board pitch math 6.67lm/m², waste 10% standard 15-20% diagonalgardencalc.ukchecked July 2026
joists 400mm centres, ~2.5lm/m²tradefoxapp.comchecked July 2026
Wickes Pro Timber Deck Board 27 x 144 x 3600mm: £12 (was £18), pressure treated UC3, 10-year anti-rot guarantee, kiln dried, grooved, 0.52 m² coverage per boardwickes.co.ukchecked July 2026
Wickes timber deckboards category: Pro 3.6m £12 (was £18), Pro 2.4m £9 (was £14), Standard 3.6m £11, 2.4m £8, 1.8m £7; Premium 28x140 board no longer listedwickes.co.ukchecked July 2026
NeoTimber Classic Hollow composite deck board 145 x 24 x 3600mm: £24 inc VAT (~£46/m²), round hollow core, 25-year residential / 10-year commercial warrantyneotimber.comchecked July 2026
NeoTimber Classic Solid composite deck board 145 x 24 x 3600mm: £29 inc VAT (~£56/m²), 25-year residential warrantyneotimber.comchecked July 2026
Composite Prime HD Deck Dual board 3600 x 143 x 22.5mm: £55.44 inc VAT per board at stockist Corker (~£108/m² boards-only)corker.co.ukchecked July 2026
Wickes Incised Exterior Grade Timber Joist 47x150mm x 3.6m, C16, UC4-spec incised treatment, 15-year guarantee: £33 (standard price, no promo)wickes.co.ukchecked July 2026
Wickes C16 treated kiln dried timber 45x95x3600mm £10 (£2.78/m); 45x145x3600mm £15 on reduction (was £17.25)wickes.co.ukchecked July 2026
Wickes C24 treated kiln dried regularised timber 45x145x3600mm £27 (£7.50/m); 45x195x3600 £36.50; no promotional pricing shownwickes.co.ukchecked July 2026
Amazon UK live listings, adjustable decking pedestals: Nicoman 10-pack 30-60mm £24.99 (£2.50/count, listing ASIN B0C19T2GCQ verified to exist); generic 10-pack 30-60mm £25.99 (£2.60/count); 60-140mm 10-pack £35.99amazon.co.ukchecked July 2026
SIPS 1000mm x 68mm galvanised self-install ground screw £26.39 inc VAT (£21.99 ex VAT) — promotional price, was £28.79; two-person install recommended at this length; free install tool over £300sipsgroundscrews.co.ukchecked July 2026
Ground Screw Centre 68mm x 650mm self-install ground screw £17.49 ex VAT, 230kg max compression load, hand/ratchet tool install, hot-dip galvanised 20-yr guarantee; in stock (this replaced the 550mm version, same price)groundscrewcentre.co.ukchecked July 2026
Blue Circle Postcrete 20kg £7.50 inc VAT a bag at Toolstation (£0.38/kg)toolstation.comchecked July 2026
Timbadeck PZ double-countersunk decking screws 4.5x65mm 500-pack £17.99 inc VAT; carbon steel, brown organic coating, corrosion-resistant, partially threaded, 4.8/5 from 1,256 reviewsscrewfix.comchecked July 2026
Same Timbadeck 500-pack listed on Amazon UK via third-party sellers at £29.99-£31.99 (roughly 65-80% over the £17.99 Screwfix price); exact price and seller fluctuateamazon.co.ukchecked July 2026
Live Amazon UK prices: ForgeFix 4.5x75 green box 200 £10.28 (2.5K reviews); ForgeFix 4.5x60 box 200 £8.20 (best seller); TIMCO C2 4.5x65 tub of 1,000 £29.99 (£0.03/count); TIMCO Classic 4.5x70 box 200 £8.00amazon.co.ukchecked July 2026
Cladco composite decking T-clip fixings and screws pack of 100: £28.34 inc VAT; stainless steel screws, plastic clips; 11 T-clips per 4m board, 8 per 2.4m board; creates 7mm expansion gapcladco.co.ukchecked July 2026
Generic universal composite T-clips with stainless screws on Amazon UK: £12.89-£13.99 per 100 pack; AVT 100-pack £13.99, 1000-pack £94.99amazon.co.ukchecked July 2026
Butyl joist tape on Amazon UK: 50mm x 20m £15.99 (£0.80/m, Amazon's Choice); HD Protect 63mm x 20m £28.99; LLPT 2-pack 50mm x 15m £18.99amazon.co.ukchecked July 2026
DDecks Protect premium joist tape 65mm x 20m: £22.94 inc VAT (£19.12 ex VAT) at Build4Less — but the listing states 'Non-Butyl Polymer Acrylic Adhesive', so it is NOT butyl and is excluded from the butyl-tape pick; cited only as evidence that branded 'joist tape' can be acrylicbuild4less.co.ukchecked July 2026
Ronseal Ultimate Protection Decking Oil 5L Natural at Screwfix: £41.49 (£8.30/L); coverage 6.4m²/L; touch-dry 90 min; recoatable in 4 hours; water-basedscrewfix.comchecked July 2026
Ronseal manufacturer claims for Ultimate Protection Decking Oil: up to 8m² per litre, 2 coats recommended, water-based, 'lasts twice as long as standard decking oil' (own weathering data)ronseal.comchecked July 2026
Ronseal Ultimate Protection Decking Oil 5L on Amazon UK: Natural £37.94, Natural Oak £37.12, Natural Pine £37.80 (8.5K reviews, 500+ bought past month)amazon.co.ukchecked July 2026
Rear overhang rules: under 1m no requirements; 1–2m the end must be made clearly visible; 2–3.05m marker boards; over 3.05m two working days' police notice plus attendant (Road Vehicles (Construction and Use) Regulations 1986, reg 82(7))gov.ukchecked July 2026
B&Q Hertz 24/7 van hire from £13/hour at participating stores; £5 annual Hertz 24/7 membership; insurance included; mileage charged separately per mile; book via app, collect from the B&Q car parkdiy.comchecked July 2026
Wickes delivery: standard from £5, next day if ordered by 6pm; orders over 375kg may incur Big & Bulky charge of £35 (free over £750 Mon–Fri), may be delivered by HiAB; Saturday +£5wickes.co.ukchecked July 2026
Travis Perkins Treated Timber Decking Board 35×148×3.6m (finished 32×144mm) £11.36 inc VAT per length; free trade account for discounted prices; 4Trade decking screws 4×65mm green qty 500 £18.14travisperkins.co.ukchecked July 2026
Travis Perkins delivery and collection: free delivery on orders over £150 (£30 below that); free one-hour click & collect from 500+ branchestravisperkins.co.ukchecked July 2026
Cladco Signature composite decking sample pack is completely free (£0.00, free courier): 8 × 50mm lengths showcasing both the grooved and woodgrain finishes, estimated 5 working dayscladco.co.ukchecked July 2026
NeoTimber composite decking samples completely free including delivery; up to 3 samples per pack; dispatched within one working day, most arrive within 2–3 working daysneotimber.comchecked July 2026
Oakdale Fencing bulk/trade deal: full pack of 3.6m treated decking boards (finished 120×28mm, ex 125×32mm) is 288 boards at £1,953.72 (≈£6.78/board, ≈125m²); packs range £1,953.72–£2,778.62oakdalefencing.co.ukchecked July 2026
Amazon UK boards benchmark: Snowdon Timber Garden Treated Decking Board 3.6m×120mm×28mm 8-pack £131.71 (£16.46/board), free courier delivery — listing confirmed to exist (ASIN B0F1TPHZLP); listings are packs/seconds, no single full-length boards at merchant pricesamazon.co.ukchecked July 2026
softwood decking £70–£90/m² supply+install; composite £80–£120/m²; hardwood £110–£130/m²mybuilder.comchecked July 2026
Doing more than just the decking?
We'll carry this over — your decking and the size you just worked out — and you can add
anything else you're thinking about: clearance, paving, decking, fencing, lawn, driveways, planting.
You end up with one brief to send to three landscapers, so they all price the same job and you can
see which one has quietly left something out.
Doing it yourselves? It sizes your materials list too. Already holding a quote?
It gives you the same numbers we'd check it against.
Never oiling again
Small, light-use decks only
Artificial grassOrder the right rolls first time, and know the price before anyone quotes you.
FencingPanels, posts and labour per metre, so you can sense-check any quote.
Gravel & chippingsHow much you need, so the path doesn't end up half-covered.
Shed baseWhich base your shed actually needs, and what it costs to get it level.