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Popular in United Kingdom

Custom

4.88 m × 3.66 m · 17.8 m²

50 boards · 14 joists · 16 posts

Drawing the 3D view…

Live4.88 m × 3.66 m17.8 m² · Composite (grey)

Drag to orbit · scroll to zoom

Width

4.88 m↑↓ 50 mm · shift ×10

Depth

3.66 m↑↓ 50 mm · shift ×10

Height off the ground

0.91 m↑↓ 50 mm · shift ×10

Shape and groundL-shape, second level, sloping ground

Deck shape

Second levelA full-width platform one step down along the front

Sloping gardenGround falls away from the house. Boards stay level, posts get longer

Railing

Stairs

PergolaOpen roof, 2.44 m of headroom

Baluster finish

Steps come down

Decking material

We sell none of them. Pick on life span and upkeep.

Capped boards in grey or anthracite, the most sold UK colours. No sealing. · 25–30 years · Wash twice a year, no coating

Board layout

The layout sets the waste allowance on the decking. The 3D view always draws the boards straight across.

Beam build

Board fixing

SceneVisual only — quantities do not change

Construction sizesOptional — defaults follow United Kingdom practice

Board widthcountry standard

Gap between boardscountry standard

Joist centrescountry standard

Post spacingcountry standard

Railing heightcountry standard

Step risecountry standard

Board length and waste

At 3.6 m you buy 50 lengths and cut off 32% of what you pay for.

3 m boards leave only 19% offcut, with a joint on each row.

Waste allowance: 5%

Straight boards: 5%

Boards run across the joists, square cuts at both ends. The allowance follows the layout and shape, not one flat figure. Change it under your rates if your own offcut pile says otherwise.

Deck area: 17.8 m²
Decking rows: 25
Boards to buy (3.6 m): 50 incl. 5% waste
Joists: 14

12 more lines, plus the cut list and the plan

Instant PDF + CSV · One payment · No subscription

See a real sample pack first

Checked against United Kingdom practice

Joist span: 1.22 m between beams, within the 3 m a 47 × 150 mm joist takes at 400 mm centres.BS 8579 / TRADA span tables — 47×150 at 400 mm centres
Frame depth: Flush beam: joists hang off the beams in 28 hangers, frame top level.
Step rise: 6 equal steps at 152 mm, within the 190 mm limit.Approved Document K — rise up to 190 mm
Guard: Guard needed at this height and included, 900 mm high.Approved Document K — guarding
Post spacing: Posts at most 1.63 m apart, within the 1.8 m maximum.BS 8579 — support spacing
Planning permission: The deck stands 914 mm above ground, over the 300 mm at which decking normally stops being permitted development. Expect a planning application, or drop the height below 300 mm.Planning Portal — decking as permitted development (300 mm)

How this is worked out

BS 8579 / Approved Document K: joists at 400 mm centres, rise up to 190 mm. Joists at 400 mm centres, posts at most 1.8 m apart, 145 mm boards with a 5 mm gap, steps at 152 mm rise, 5% waste added to the decking. A materials list, not a structural design — have it checked before you build.

Read every rule and formula we use

Site and access notes

Height and ground: Boards sit 914 mm above ground, so the frame stands on 16 posts in 16 footings. Keep the area under the deck clear for inspection.
Footings and concrete: 16 holes, 48 bags of post-set to mix. Check for drains, cables and tree roots before digging.
Longest piece to carry in: 3.6 m boards. Measure the side gate or the through route before ordering; if it will not go through, order shorter lengths and the cut list changes with it.
Getting on and off: 6 steps at 152 mm rise on 3 stringers, off the 0.91 m level.
Edge protection: 11.28 m of railing, 12 posts at 900 mm high.
Ground cover: Weed membrane 17.8 m² under the deck, laid before the frame goes down.

Materials list done. Ready to order and build?

Buy once, cut once, build it square — $9

A missed fixing or a wrong length usually means another trip to the yard. The Full Build Pack is worked out from this exact drawing:

Shopping list for the yard
Every line and quantity, grouped by timber, sheets, fixings and concrete.
Cut list on stock lengths
Which piece to cut from which length, so less ends up as offcuts.
Dimensioned plan
Every measurement, plus the diagonal to mark it out square.
Build order
Stage by stage, from the ground up.

Sketches of the page layout. Your pack is filled in from this drawing. See a full sample

Deck build pack

Your project

Builders can put their company name on the cover so it goes to the customer as theirs.

Pay once, no account needed first. Use the email you want the job kept under; we set up your login from it after payment.

One payment
No subscription
No account needed first
PDF + CSV straight away
Delivered immediately

Preview a full sample pack (opens in a new tab)

How the cut list reads (example layout)

Each stock length the yard sells, with the pieces to cut from it and what is left over.

Merchant order sheet · ground marking-out · build order

98 lengths to buy · 50 deck boards · 16 posts

Filled in for this job with the $9 pack

What $9 adds

Full material quantities beyond the free preview
Dimensioned framing plan and the exact cut list, packed into stock lengths
CSV merchant order file, ready for a supplier or spreadsheet
Marking out: the diagonal to pull so the frame is square before anything is fixed
Merchant order sheet: only things a merchant can hand over, each line checked and in your own units, with a box to tick
Build order: each stage in sequence, with the check that goes with it
Your company name on the PDF and the shared page, with our line gone

What the pack is not

Not a structural design or an engineer's sign-off
Not planning permission or building-control approval
No prices: you get the exact list to price with your merchant
No electrics, plumbing or interior fit-out

Building it yourself? One length cut short costs more than this pack. You get the diagonal to square the frame, the counter sheet to tick off at the yard, and the order to build in.

Quoting a customer? The same job goes out under your own name, with our line gone. Per job, no subscription to start.

Still free: the 3D drawing, the materials list on screen, a summary PDF and your own prices.

Free design record

Overall measurements, design summary and regional checks. Free, with no account.

Don't know the prices yet? That's normal.

We don't guess a price, because timber costs change from town to town and week to week. Take the exact list to your local timber merchant and ask for a quote on it. A complete list gets you a real price, not a ballpark. Then type those prices here to see the total.

Your costs

Timber prices change weekly and differ by yard, so we never guess them. Type one number below and you get a figure straight away.

Quick price in one number

What do you pay for composite (grey) decking, per m²? That alone gives you a figure. Add the rest of your rates below when you want the full picture.

Composite (grey) decking

£ / m²

Saved on this device. Sign in and they follow you anywhere.

Pressure-treated softwood

£ / m²

Cedar / larch

£ / m²

Composite

£ / m²

Tropical hardwood

£ / m²

Frame, posts and footings

£ / m²

Railing

£ / m

Per step

Pergola

£ / m²

Labour

£ / m²

Waste allowance

Set from the board pattern and shape. Type a number to fix your own.

Overheads and margin

VAT

Your design summary

Save the design, overall measurements and regional checks as a PDF. The complete merchant and site files are in the paid pack.

Customer nameSite address

Notes for the customer

How to design a deck online

Pick your country and metres or feet, or start from a popular size.
Set the size and shape: rectangle, L or U, and the height above the ground.
Choose timber or composite boards, then add steps, a railing or a pergola.
Read the list of what to buy, with the warnings on spans, height and posts.
Add your own supplier rates if you want a cost. Leave them out for quantities only.

Free on screen, and what the pack adds

The 3D model, the checks and a summary PDF are free with no sign-up. The paid build pack adds the dimensioned plan, the cut list, the yard order sheet and the build order for that one job. See a real sample pack.

What this deck designer gives you

Deck boards by row and stock length, with the board gap allowed for.
Joists, rim joists and beams at your country's usual spacing and sections.
Posts and footings, steps with stringers, and railing with the opening at the stairs.
Screws or hidden clips counted from the board runs.
An open-roof pergola with its posts and rafters, if you add one.

Countries and units

Pick the UK, Ireland, the US or Canada and switch between metres and feet. Joist spacing, timber sections and board sizes follow that country's common practice, so the list matches what a local merchant or yard stocks.

Prices and what this is not

There are no built-in prices or national averages. A cost appears only when you enter your own supplier rates. The result is a planning materials list of quantities, not a structural design: check spans, footings and approvals with your local building rules or an engineer.

How every quantity is worked out is on the methodology page. To turn the list into a cost, read how to price deck materials with your own merchant rates.

Check one part of your deck

4.88 m × 3.66 m · Composite (grey)

17.8 m² · 98 lengths to buy (50 deck boards)