Best Deck Stain for NZ Conditions: UV, Rain, Salt and Timber Type
The best deck stain for NZ conditions is a penetrating, water-based stain with UV-resistant pigments and mould inhibitors, matched to your timber and applied over a properly prepared surface. MASTERMAX makes two for decks: DECKMAX, a semi-transparent stain for pine and hardwood, and ULTRAMAX, a water-based oil stain designed to work in one coat.
What NZ Conditions Do to a Deck
UV breaks down the timber surface and fades colour, especially on sun-facing decks.
Rain and humidity feed mould, moss and algae, particularly on shaded decks.
Dirt, grease and salt left on the surface stop stain from soaking in, which is why surface prep matters so much.
Foot traffic and furniture wear the finish fastest in the places you use most.
What to Look for in a Deck Stain
Penetration. A stain that soaks into the timber is less likely to peel than a coating that sits on top.
UV protection. Look for UV-resistant pigments or UV absorbers, which slow fading and greying.
Mould inhibitors. These help the finish resist mould and mildew in damp conditions.
A water-based, low-sheen formula that cleans up with soap and water.
Suitability for your timber, whether that's pine or a hardwood such as kwila.
Easy maintenance. A good stain can be recoated without stripping.
DECKMAX vs ULTRAMAX at a Glance
DECKMAX | ULTRAMAX | |
Type | Water-based oleoresinous and acrylic blend with linseed oil | Water-based oil stain with modified linseed oil |
Look | Semi-transparent and low sheen, with the grain visible | Transparent and low sheen, enriching the grain |
Coats | Two | One on most timbers |
Coverage | 6 to 8 m² per litre | 6 to 10 m² per litre |
Drying | Recoat on new pine after at least 2 hours and on other surfaces overnight, and wait 24 hours before light foot traffic | Touch dry in 24 hours and fully cured in up to 48 hours |
Colours | Six: Hardwood Red, Black Beech, Dark Walnut, Rustic Cedar, Honey Oak and Black Char | Natural, Kwila and Charcoal |
Reapply | When the timber shows heavy weathering, typically every 2 to 3 years | Every 2 to 5 summers, or when wear or fading shows |
Best for | Pine and hardwood decks, outdoor furniture and fences | Decks, outdoor furniture, fences and weatherboards |
Deck Oil vs Deck Stain
The line between oil and stain has blurred. Both penetrate the timber instead of sitting on top like paint. A stain adds pigment for colour and UV protection, while an oil feeds the timber and enhances the grain. ULTRAMAX is a water-based oil stain with modified linseed oil and UV absorbers, so it does both jobs. DECKMAX blends linseed oil with resins for a harder, walk-on finish. If you'd rather have a solid colour that covers the grain, paint is the other option, and our guide to deck paint vs stain explains the trade-offs.
Choose by Timber
New pine should weather outdoors for 8 weeks before staining. Shiny, mill-glazed machined surfaces may need sanding so the stain can penetrate.
New hardwood should weather for at least 12 weeks, so oily tannins can leach out. Rinse it with water several times during that period.
New hardwood absorbs less on the first coat, so a DECKMAX recoat may be needed earlier.
Dressed timber can need more frequent reapplication because it absorbs less to begin with.
Prep and Conditions
Clean the deck with PREPMAX, which cleans, brightens and treats mould. Our guide to PREPMAX vs GET-GONE explains which to use.
If there's mould, moss or lichen, treat it first and leave the treatment for at least two weeks. Then remove the dead material and let the timber dry.
Avoid steel wool and wire brushes, because they can leave iron stains on timber.
Apply ULTRAMAX on a fine day between 5°C and 30°C, and DECKMAX above 10°C. Avoid rain for at least 24 hours.
Test your colour on an offcut or a hidden board first, because the colour can look different once it dries.
Which One Should You Choose?
Choose DECKMAX if you want a semi-transparent colour, a harder walk-on finish and a choice of six colours.
Choose ULTRAMAX if you want to finish in one coat and show the natural grain of the timber.
Choose DECKMAX for a fence as well as a deck. It can be used as a semi-transparent fence stain.
Choose paint instead if you want to hide the grain or cover an old, patchy surface. See How to Stain Your Deck Like a Pro for the application steps.
Frequently Asked Questions
What is the best deck stain for NZ conditions?
The best deck stain has UV-resistant pigments, mould inhibitors and a penetrating, water-based formula that suits your timber. MASTERMAX's DECKMAX is a semi-transparent stain for pine and hardwood, and ULTRAMAX is a one-coat oil stain. Both need proper prep.
Is deck oil or deck stain better?
Both penetrate the timber. A stain adds pigment for colour and UV protection, while an oil feeds the wood and enhances the grain. ULTRAMAX is a water-based oil stain that does both, and DECKMAX adds resins for a harder walk-on finish.
How long does deck stain last in NZ?
It depends on the timber, the prep and how exposed the deck is. DECKMAX typically needs reapplying every 2 to 3 years or when the timber shows heavy weathering, and ULTRAMAX every 2 to 5 summers. Clean the deck each year.
Do I need to prepare a deck before staining?
Yes. The surface must be clean, dry and free of dirt, grease, mould and salt. Clean with PREPMAX, treat any mould and wait two weeks, and let new pine weather for 8 weeks and new hardwood for at least 12 weeks before staining.
Can you stain a deck in winter?
Only in the right conditions. ULTRAMAX needs a fine day between 5°C and 30°C, and DECKMAX needs temperatures above 10°C. Avoid rain for at least 24 hours after applying, and check the product's data sheet before you start.
Can you stain over an old stain?
Often, yes, if the old stain has weathered and the timber is still absorbent. Clean it first with PREPMAX and check that water soaks in instead of beading. If water beads, the surface needs more cleaning before you apply a new stain.
