How Much Will it Cost to Build a Deck?

26th June 2024

A well-constructed timber or composite deck is an attractive addition to your home and will undoubtedly increase its resale value.

Naturally, when you start to think about landscaping your home, you first ask yourself, "How much is this going to cost me"? So, this is the first in a series where we will attempt to demystify the costs involved so you can more appropriately plan around your budget.

How much will it cost to build a deck in a small backyard?


When it comes to decking, the overall price will be determined by choice of material, the width, ease of installation and the base (ground/concrete) on which the deck will be installed. The guide below gives a cost range per sqm (ex GST) considering these differences. The ranges are intended as a guide; the final cost will depend on your site and circumstances.

**Note: to ensure the quality of our craft and the longevity of your installation, we ONLY work with trusted suppliers and the most reputable products, low-end or high-end.

When you receive quotes from builders, be sure to confirm the credentials of their suppliers and materials; a cheap pine deck will be just that—cheap, poorer quality, and more prone to the problems indicated below.


We have also included a brief guide to the most common materials - treated pine, hardwoods and composite - and the pros and cons of each one.

Treated Pine

If budget is the deciding factor, then using a good-quality treated pine is the best option.

Treated pine is the least expensive option on the market; however, the factors that make it less costly are the factors that make it the least hardy. Pine is fast-growing, therefore less dense and much softer than hardwoods. Because of this, it is particularly prone to swelling, shrinkage, and movement, which are made worse by the high humidity and intense UV we experience in New Zealand. It is also more prone to mould growth during winter and pressure dents in high-traffic areas.

Additionally, pine is generally painted or stained to make it more visually appealing; however, due to NZ's climatic conditions, stains and paints will fade and crack over time and must be re-applied to keep the deck looking tidy.

Pine has the shortest lifespan of all three options; if not regularly maintained (cleaned, oiled, stained), it can be as short as ten years, but regular maintenance can last fifteen years and beyond.

Because of these drawbacks, we only use the highest-quality treated pine to ensure you get the best price-to-quality ratio on the market. The pine we use is FSC* certified, arsenic-free, chrome-free, and preserved to a very high level.

*FSC is the Forest Stewardship Council, a non-profit organization that sets certain high standards to ensure that forestry is practised in an environmentally responsible and socially beneficial manner.

Premium pine decking
Our team installed this premium pine deck in Hobsonville Point, Auckland.

Hardwoods (Vitex, Purple Heart, Kwila, Garapa)

If budget constraints are less of an issue and you are more concerned about the aesthetics of your space, hardwoods are an attractive option.

As the name suggests, hardwoods are highly durable and hardwearing. They are also very dense and have a more high-end look than pine. However, hardwoods are the least eco-friendly option due to their slow growth and the fact that they are imported.

Hardwood decks must be cleaned and oiled once a year for maintenance, but they have a lifespan of 25 years and beyond. It is also common for hardwood timbers to develop hairline cracking, which is a natural part of the ageing process. Some hardwoods can bleed in the first month after installation.

It's important to note that most hardwoods will eventually fade to more or less the same colour, a lovely driftwood grey.

Vitex small garden pathway
We used quality Vitex to construct this small garden pathway.


Composite timbers are increasingly popular and widely available, and they are a bit like the Ferrari of decking!

Composites are expensive but by far the highest-performing in terms of maintenance, longevity, durability, ease of installation, and eco-friendliness. We use Modwood composite decking, which comprises around 90% recycled materials (milk bottles and reclaimed pine waste).

Modwood decking is designed not to fade, warp, crack, or splinter under the harsh NZ sun and doesn't need sanding, oiling, or staining. It is both GreenTag and Codemark certified.

There are really no downsides to Modwood composites; it will mostly depend on your aesthetic preferences.

Modwood deck
Magnetic Grey Modwood deck installed by our team in Hobsonville Point, Auckland.

Ultimately, your choice of material will depend on your budget, style, and how much you are prepared to maintain it. We hold several timber samples in our warehouse, so we can help you find the right material for your needs.

Our team specialises in small urban gardens, terraced housing, balconies, and decks, and we have an in-house builder for all timber constructions. If you are considering transforming your outdoor space, don't hesitate to contact us for a no-obligation consultation.

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