Decking for Irish Weather.
Timber vs Composite.

Timber decking

Pressure-treated softwood (mostly Scandinavian pine or spruce) is what most Dublin garden decking is built from. It's affordable, widely available from yards like Murdocks and Chadwicks, and a competent crew can install it cleanly. Lifespan in Irish conditions is realistically eight to twelve years with proper care — meaning an oil or stain every year or two and the occasional board replacement.

Hardwood (iroko, balau, occasionally European oak) lasts longer — fifteen to twenty years and beyond — and looks the part. The trade-off is cost, skill to install, and inconsistent availability for some species. Specialist timber merchants like Brooks Bros stock it; general builders' merchants might not.

The maintenance reality. Timber needs annual care. If you skip a year you'll see it — the boards grey, splinter, and start picking up moss on shaded edges. Most Dublin homeowners are fine with that if they know up front. The ones who get caught out are the people who were sold the install without anyone mentioning the upkeep.

How timber fails in Irish weather. Three main failure modes:

• Joist rot at contact points. Where the sub-frame meets the ground or wall, damp sits. Without proper isolation (plastic feet, DPC tape, ventilation gap), the joists go before the boards.
• Algae and moss on shaded sides. Particularly bad on north-facing decks or decking that runs along a high wall. Timber stays wet long enough for green growth to take hold.
• Splintering and grey-out. Oils dry out, the surface roughens, splinters start. An annual clean and re-oil prevents most of it.

Composite decking

Wood-plastic composite (WPC) boards are made from recycled timber fibres bound in plastic. The pitch is low maintenance — wash with soapy water once a year, that's about it. The trade-off is higher upfront material cost and a slightly less natural look (though modern composite has come a long way).

Capped vs uncapped. Capped composite has a sealed top layer that resists staining, fading and surface scratches. Almost all decent composite sold in Ireland now is capped. Uncapped is older-generation and worth avoiding — it picks up stains the way an old kitchen counter does.

Lifespan. Quality composite is good for twenty to twenty-five years. It doesn't rot, doesn't splinter, doesn't need oiling. Colour fades slightly over the years but doesn't blotch.

How composite fails in Irish weather. Two main things to watch:

• Slippery when wet. Older composite can get genuinely slick in the rain. Modern textured boards address this — worth specifying when ordering, especially for a north-facing or steps-heavy installation.
• Tannin stains from leaves. If oak or apple leaves sit on the deck through a wet autumn, they'll mark uncapped composite. Capped boards rinse clean.

The bit that decides how long it all lasts

The sub-frame, ventilation, drainage and fixings matter more than the boards on top. Get these wrong and a thousand-euro composite deck fails as fast as a budget timber one.

• Sub-frame: pressure-treated softwood joists at the right spacing (usually 400–500mm centres). This is the part that usually fails first, regardless of what's on top.
• Ventilation gap: minimum 25mm clear under the deck. Without it, damp gets trapped, joists rot from below. Side venting (slatted edge boards) helps in fully enclosed Dublin courtyard gardens.
• Drainage: the deck needs a slight slope (1–2%) away from the house. Water pooling at the wall is a house problem, not just a deck problem.
• Fixings: stainless steel or quality coated screws. Standard steel rusts in Irish damp inside two winters, staining the boards around it.
• Steps and integrated lighting: design these in from the start. Retro-fitting lights through a finished deck involves lifting boards and running cable.

Which material for which Dublin garden

• Family garden, budget-conscious, sunny aspect: pressure-treated softwood timber. Eight to twelve good years if you keep up the oiling.
• High-use garden, BBQs every weekend, kids and pets: composite. No splinters, easy to clean, holds its look through heavy traffic.
• Heritage house or larger garden where the look matters: hardwood timber. More upfront, looks the part, lasts a long time.
• North-facing or shaded garden (common in Dublin terraced houses): composite, textured. Timber stays wet too long in those conditions.
• Coastal exposure or particularly windy site: composite. Salt air and constant wind dry out timber oils faster.

What we won't do

• Install over a sub-frame we haven't built or fully inspected — we don't take responsibility for someone else's joists
• Cut corners on the ventilation gap to get the deck flush with a step or doorway — it'll fail and we'd rather not put our name to it
• Recommend hardwood when softwood does the job and you weren't planning to maintain hardwood properly

Common Questions

How long does decking last in Dublin?

Pressure-treated softwood timber lasts 8–12 years with proper care. Quality composite lasts 20–25 years with minimal maintenance. The sub-frame underneath and the ventilation gap matter more for lifespan than the boards on top.

Can you deck a north-facing garden?

Yes. For north-facing or shaded gardens we recommend composite over timber. Timber stays wet too long in low-light spots, which accelerates algae and rot.

Do I need planning permission?

Most ground-level or low-raised decks under 25m², attached to your own house, are exempt. Raised decks over 1.2m near a boundary may need permission. We flag it during the site visit.

How do you stop decking going green or mossy?

Proper ventilation gap underneath (25mm minimum), an annual clean, and textured surfaces on shaded sides. Composite handles it better than timber from the start.

Can old decking be repaired board-by-board?

Sometimes, if the sub-frame is still healthy. The joists usually fail before the boards. We'll check during the site visit and tell you straight.

Related Services

• Decking — timber and composite installations across Dublin.
• Garden Design — when the deck is part of a wider reworked layout.
• Garden Revival — for tired gardens being brought back generally.