A 20 m² terrace budget is easiest to control if you split it into clear cost blocks: foundations, substructure, decking, fasteners/accessories and labour. The exact numbers depend on your country and material choice, but the structure below works well as a reusable template.
Typical total cost band
For a standard wooden terrace in Europe, guides suggest about 90–180 EUR/m² including materials and labour. For 20 m², that means a broad total range of roughly 1 800–3 600 EUR, with composite or premium solutions often landing at the upper end or above.
Cost blocks and usual percentages
For a “normal” 20 m² project, the budget commonly splits like this:
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Foundations: 10–25% of total (pads, small concrete footings or screw piles).
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Substructure: 15–25% (joists, beams, supports, connectors).
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Decking boards: 30–40% (wood, composite or plastic surface).
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Fasteners & accessories: 5–10% (screws, clips, edging, spacers).
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Labour: 30–50% (strong share on smaller terraces if not DIY).
Example mid‑range timber terrace (around 140 EUR/m²)
Using a mid‑range reference of about 140 EUR/m² for wood (within the 90–180 EUR/m² span), the total for 20 m² is about 2 800 EUR. A realistic breakdown could look like this:
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Foundations: ~400–500 EUR
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Simple ground prep, support pads or small footings; more if ground is uneven.
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Substructure: ~450–550 EUR
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Pressure‑treated joists and beams, brackets, post supports.
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Decking boards: ~800–1 000 EUR
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Mid‑grade treated or larch decking, roughly 40–50 EUR/m² for boards alone.
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Fasteners & accessories: ~150–250 EUR
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Outdoor screws, possible hidden clips, edge trims, spacers, small drainage details.
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Labour: ~800–1 000 EUR
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1–2 installers for several days; labour often comes close to or exceeds material cost on small decks.
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Example impact of choosing composite
Cost comparisons show composite decking has a higher purchase price but lower maintenance needs than timber. If you keep the same structure and foundations but switch from mid‑range wood to composite, the decking block might increase from about 800–1 000 EUR to 1 200–1 600 EUR for 20 m², pushing the total closer to 3 200–3 600 EUR.
How to turn this into a project‑ready budget
To convert this template into a concrete offer, you can:
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Fix your target quality level (budget / mid‑range / premium) and apply a specific EUR/m² rate per scenario.
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Insert your real material purchase prices and local labour rate instead of the example ranges above.
That way you get a clear, itemised budget for a 20 m² terrace that you can present to clients or use as an internal planning tool.
