Choosing a wood for a Geneva deck

Larch, cedar, or ipé? Three good answers — and the one you should probably pick depends a lot less on the wood and a lot more on what your garden looks like at the end of November.

Geneva weather isn't kind to outdoor wood. We get hot, dry summers, then weeks of cold rain in autumn, then deep frost — and that whole cycle pulls the moisture in and out of every board on your deck four times a year. Pick the wrong wood and you'll be replacing boards in eight years. Pick a sensible one and you'll forget about it.

Here's how I think about the three most common choices, in plain language, with no vested interest in selling you the expensive one.

Larch (mélèze)

If I had to pick one wood for a Geneva deck and never explain myself, I'd pick larch. It's grown in the Alps, it's used to our weather, and it's about half the price of imported hardwoods. Out of the box it's a warm honey-orange; left alone it greys to a soft silver in two or three summers.

Larch is durable, oily enough to resist rot, and locally available — meaning shorter delivery, less freight, and a smaller footprint. The downside: it splits a little more than ipé, and the surface picks up scuffs faster. Most clients are perfectly happy with that trade — it's a deck, not a museum piece.

Cedar

Cedar is the soft option — light, dimensionally stable, and nearly impossible to rot. It's also forgiving to walk on barefoot in summer because it doesn't get as hot as denser woods. The trade is hardness: cedar dents. If you've got kids dragging metal chairs across the boards, you'll see it.

I usually recommend cedar for raised platforms, smaller decks, or anywhere you'll spend time barefoot — terraces off bedrooms, sauna surrounds, that kind of thing. Less ideal as a heavy-traffic family deck.

Ipé (and other tropical hardwoods)

Ipé is the premium answer. It's so dense it sinks in water, it shrugs off insects, and a properly built ipé deck can outlast the house it's attached to. People love the rich brown colour. Two reasons I rarely recommend it as a default:

• Cost. Roughly 2–3× the price per square metre versus larch, and the fittings cost more too because every screw needs a pre-drilled hole.
• Provenance. Most ipé is South American; even with FSC certification it's hard to feel great about flying tropical hardwood to Switzerland when we have an excellent native option.

So what should you actually pick?

If you don't have a strong reason to go premium, larch is almost always the right answer in Geneva.

Pick cedar if you'll be barefoot most of the time, or if the deck is small and visually prominent. Pick ipé if budget genuinely isn't a concern and you want something that looks magnificent and never moves. For everything in between — the family deck, the BBQ deck, the don't-think-about-it-for-twenty-years deck — pick larch.

Whatever you pick, get the substructure right. The wood you walk on is half the deck; the joists and lambourdes underneath are the other half. A premium board on a cheap frame will fail before a sensible board on a proper one. Always.