Decking boards: timber, thermowood or composite for a new terrace

Ordinary softwood: the cheapest start, the most work later

Pressure-treated pine or spruce is the material most terraces in Harju county are still built with, mainly because it is the cheapest to buy and easy to source from any timber merchant. Expect to pay roughly 10–18 € per square metre for the boards themselves, depending on thickness and treatment class, before any building work.

The trade-off is maintenance. Softwood decking needs oiling or re-treating roughly once a year to keep water out of the end grain and the fixing holes, and if you skip a season the boards start to grey and split. Our guide on oiling versus varnishing an existing deck covers that upkeep in detail once the terrace is built.

In an Estonian winter, softwood copes reasonably well structurally, but standing water and freeze-thaw cycles are hard on any coating that is starting to fail. A board that was not oiled properly in autumn is more likely to crack or lift a fixing by spring.

Thermowood: a pricier material with fewer surprises in winter

Thermowood is ordinary softwood heat-treated to change its structure, making it more dimensionally stable and considerably less prone to soaking up water. It costs more than untreated pine, typically 20–35 € per square metre for the boards, but it moves less with humidity and holds up better through repeated freezing and thawing.

It still benefits from an oil treatment, but less often than raw softwood — many owners find every second year is enough rather than every spring. The wood itself does not rot as readily, so the maintenance is more about appearance than protection.

For a Harju county terrace that sits in full sun or full shade, thermowood is usually the more forgiving choice, since it is less likely to cup or gap noticeably as the seasons change. It is a sensible middle option if you want something better than pine without moving to composite.

Composite: the highest price, the least annual upkeep

Composite decking, made from wood fibre bound with plastic, sits at the top of the price range, generally 35–55 € per square metre for the boards alone. It does not need oiling, staining or annual treatment of any kind, which is the main reason people choose it despite the cost.

It handles Estonian winters well in terms of rot and moisture, since there is no bare wood to soak up water, but it does expand and contract with temperature more than people expect, so the fixing system needs to allow for that movement. Cheaper composite boards can also feel noticeably colder and harder underfoot than timber in winter.

The saving is almost entirely in time rather than in the build itself: no sanding, no oil, no colour to touch up. Over ten or fifteen years that can offset the higher purchase price, but only if the substructure underneath is built correctly, since composite does not forgive a poorly ventilated frame the way timber sometimes does.

How to decide when budget and time are both limited

If the deciding factor is upfront cost and you are prepared to oil the boards every spring, ordinary pressure-treated softwood is a reasonable choice and not a false economy, provided you actually keep up the maintenance. Where it becomes expensive is when the oiling gets skipped for a few years and boards need replacing early.

If you want a middle ground that still looks and feels like wood but asks less of you, thermowood is usually the better use of a moderate budget. If your priority is minimal annual work and you are not particular about the exact tactile difference from timber, composite is worth the extra outlay.

• Tight budget, willing to oil yearly: pressure-treated pine or spruce
• Moderate budget, want fewer surprises through winter: thermowood
• Higher budget, want minimal annual maintenance: composite
• Full sun exposure or a lot of standing water nearby: thermowood or composite over raw softwood
• Planning to sell within a few years: match the material to what similar houses nearby use

What the build itself costs on top of the material

The boards are only part of the bill. The substructure — joists, ground preparation, damp-proofing where the frame meets soil, and getting the fall right so water drains away from the house — usually takes more labour hours than laying the boards themselves. This is where a badly built frame undermines even the best material.

Our decking and terraces service starts from 90 € per job for straightforward work, with a fixed quote given once we have seen the site or photos and know the dimensions and ground conditions. For terraces that connect to an existing floor level indoors, our flooring service, from 15 € per job, can also be relevant where boards run into an interior room.

Hourly work, when it applies, is billed from 39 € an hour with a 25 € call-out in Tallinn that is deducted if the job goes ahead, but a new terrace build is normally quoted as a fixed price once we know what is involved. That figure is what you pay, regardless of how the weather or the ground behaves on the day.