How to treat teak: the complete care guide

Buy teak and you are immediately handed a pile of contradictory advice: oil it, don’t oil it, sand it every year, never sand it. The honest answer is simpler than the shelves of a DIY store or garden centre suggest. In many cases, treating teak is a choice, not a duty. This guide takes you through a few decisions to the route that suits your furniture, with the steps for each route. For the details of each situation, we point you to the more in-depth pages of our care guide.

Want to know what kind of wood teak actually is first? Read all about teak wood.

First: teak needs very little by itself

Teak is a naturally oily wood. The Dutch timber information centre Centrum Hout describes its surface as feeling “soft” and slightly greasy because of the oily substances in the wood, and rates teak in durability class 1 to 3 against fungal decay, depending on where it grew (Centrum Hout, Dutch).

Makers of teak garden furniture are strikingly unanimous:

• Gloster: “Contrary to popular belief, teak furniture does not require any special maintenance routine or any additional protection apart from occasional cleaning” (Gloster).
• Tribù: teak left in its natural state is “virtually maintenance-free” and can stay outside all year round, even in extreme weather (Tribù).

So there are really two reasons to treat teak: you want to keep its colour, or you want better protection against stains and dirt. If neither matters to you, doing nothing is a perfectly good option.

The decision tree at a glance

1. Is the furniture indoors or outdoors?
   • Indoors → see Route C: indoor teak.
   • Outdoors → go to question 2.
2. Do you want to keep the golden-brown colour, or can it go grey?
   • Grey is fine → Route A: let it go grey.
   • Keep the colour → Route B: keep the colour.
3. Is the teak new or already weathered? Each route has separate steps for new and weathered wood.

For more on outdoor pieces, read outdoor teak care; for chairs, benches and lounge sets, see teak garden furniture care.

Keep the colour or let it go grey?

This is the most important choice, and it is mostly a matter of taste.

What happens if you do nothing. Outdoors, untreated teak changes from golden brown to a light silvery grey (gray, in US spelling) as the pigments in the surface layer of the wood fade. According to Gloster this takes six months to two years, depending on the location and the weather (Gloster). Tribù stresses that it is a cosmetic process that does not harm the strength or quality of the wood (Tribù).

What you need to do to keep the colour. You choose a sealer: Tribù describes such a product as containing UV protection to slow down greying, plus a fungicide against mould and mildew (Tribù). Gloster advises that teak you want to keep looking “fresh out of the box” should be sealed when new, and that the treatment is repeated every year (Gloster). Keeping the colour therefore means yearly maintenance.

Still undecided? Letting teak go grey sets out the pros and cons of a silver-grey patina.

Route A: outdoors, let it go grey

The route with the least work, and according to Gloster the one it recommends itself: let the teak weather naturally and clean it thoroughly once or twice a year (Gloster).

New teak (route A)

1. Choose the spot with care. New teak releases natural oil and pigment at first. According to Gloster this “bleeding” subsides after around two to three months. During that period, don’t stand new teak on pale, porous stone paving, and keep light-coloured cushions off and away from it in wet weather (Gloster). Vincent Sheppard gives the same advice (Vincent Sheppard).
2. Accept the in-between stage. Tribù calls the irregular discolouration or “watermarks” on new teak part of the natural maturing process; you can remove them by gentle washing with a teak cleaner (Tribù). According to Vincent Sheppard, colour variations in new teak diminish with sunlight, which can take weeks to months (Vincent Sheppard).
3. Beyond that: nothing. No oil, no varnish.

Weathered teak (route A)

1. Clean once or twice a year. Use water with a mild detergent, or a dedicated teak cleaner, and work with a cloth, sponge or soft brush (Gloster).
2. Sand lightly if needed. Gloster says teak may benefit from occasional light sanding to remove raised grain and restore a smooth surface. Always sand along the grain, never across it (Gloster).
3. Optional: stain protection without colour. Untreated teak is not stainproof (Vincent Sheppard). If you want to keep the grey but have less trouble with stains, you can use a colourless protector. Gloster describes applying such a protector over the weathered surface to repel moisture and prevent food and drink stains (Gloster); Tribù describes protection against stains and green deposits without colouring the wood (Tribù).

For stains, green deposits and dirt, read cleaning teak.

Route B: outdoors, keep the colour

Here you deliberately choose a yearly treatment. The principle is the same for every manufacturer: clean thoroughly first, let it dry completely, then protect with a thin coat.

New teak (route B)

According to Gloster (source):

1. Wear eye protection and rubber gloves, and cover the ground under your work area.
2. Clean first, even though the furniture is new: the cleaner removes the natural teak oils from the surface so the protective product can bond.
3. Let the wood become 100% dry and free of dust. If it feels rough after cleaning, sand lightly first.
4. Test on a hidden spot to see whether you like the colour.
5. Apply a very thin coat of sealer with a cloth; for its own sealer, Gloster specifies a second thin coat after 30 minutes. Always follow the drying times on the label of the product you use.
6. Add a protector on top if you like. Gloster advises a protector over the sealer to repel moisture and prevent stains.
7. Repeat at least once a year.

Tribù describes the same order: a sealer can go on new or old teak as long as it has been cleaned, and if you apply the sealer every season, a simple clean with water and pH-neutral soap will do for years (Tribù).

Weathered teak (route B): bringing the colour back

If your teak has already gone grey and you want a warmer colour again, start with more thorough work:

1. Clean thoroughly with a teak cleaner. Gloster describes wetting the wood, spraying on the cleaner, leaving it to soak in for about three minutes, removing dirt with a scrubbing pad, rinsing thoroughly with clean water and letting it air-dry (Gloster).
2. Sand if the wood feels rough, lightly and along the grain (Gloster). Wear a dust mask when sanding and vacuum up the dust: Centrum Hout notes that substances in teak can cause skin conditions in sensitive people (Centrum Hout, Dutch).
3. Let it dry completely and remove all dust.
4. Test, then seal thinly, as for new teak above.

If there is a lot of mould, old oil or varnish on it, or the piece really needs restoring, read how to restore teak.

When to treat outdoor teak

Gloster gives a concrete tip: apply the protector once a year, and on table tops twice a year, in April and October, so those more exposed horizontal surfaces are better protected through the winter months (Gloster). For the sealer, Gloster says at least once a year; Tribù talks about applying it every season (Tribù).

Pick a dry spell for the job: Gloster stresses that the wood must be completely dry before you apply a sealer, and that after the second coat the protector needs 48 hours to dry before you use the furniture again (Gloster).

For tables specifically (indoor and garden), there is a separate guide: teak table care.

Teak oil, sealer or protector: what’s the difference?

This is where most of the confusion lies, because shops often display “teak oil” prominently next to teak furniture.

Product	What it does (according to the sources)	Outdoors?
Teak oil / wood oil	Teak is already oily; extra oil adds no protection and does not stop it going grey	Advised against by Gloster, Tribù and Vincent Sheppard
Sealer	Keeps the colour longer (UV protection), with a fungicide against mould; breathable, not a varnish	Yes, if you want to keep the colour
Protector	Colourless protection against stains, moisture and green deposits	Yes, on new, sealed or grey teak
Varnish / paint	Doesn’t adhere well to oily teak and starts to peel	Advised against by Gloster and Tribù

Why no teak oil outdoors? Gloster says it does not recommend teak oil or any other wood oil on teak used outdoors. If the wood is oiled regularly, mildew can form on the oil left on the surface and the teak gradually turns black, a colour that “can then only be removed with aggressive sanding” (Gloster). Tribù also advises against oil (especially linseed oil) and varnish: oiling does not prevent greying and often leads to mould and mildew, and removing that takes bleach, soap and sanding. In Tribù’s words: “Tribù and authorities from the timber profession itself tend to advise against the use of teak oil” (Tribù). Vincent Sheppard advises against oil on outdoor teak too, because extra oil adds no extra protection (Vincent Sheppard).

Not everyone agrees. The US site of furniture retailer Castlery, for example, recommends teak oil as a step when restoring outdoor teak (Castlery US). Its guide does not address the mildew risk that the manufacturers above warn about. That is why this guide follows the manufacturers.

Why no varnish outdoors? Because teak is naturally oily, paint or varnish does not adhere properly, according to Gloster, and after a short while starts to peel off (Gloster).

A fuller comparison, including product categories, is in teak oil or sealer.

Route C: indoor teak

Indoors the weather plays no part: no rain, no greying from the elements. Centrum Hout in fact describes teak heartwood as turning darker when exposed to light (Centrum Hout, Dutch). The manufacturers’ advice against oil applies explicitly to teak used outdoors. Indoors, according to Centrum Hout, teak can be finished with oil or nitrocellulose lacquer, provided the surface is freshly sanded or degreased, and table tops are often treated with acid-curing lacquer. Centrum Hout does rate the finishability of teak as only “moderate” (Centrum Hout, Dutch).

New, untreated teak indoors

Indoors, untreated wood is prone to stains: the natural colourants in untreated wood dissolve in water, which can cause colour differences (Meijs Wonen, Dutch). If the piece gets heavy use, like a dining table, a protective finish is sensible. The usual options:

• Water-based colourless protector: barely changes the colour and protects against dirt and water marks, but less well against grease. The Dutch teak furniture company Troedoor advises two or three coats for a first treatment, then topping up three or four times a year (Troedoor, Dutch).
• Water-based impregnating oil: protects better against water, grease and oil, and may darken the wood slightly; two or three coats, with a light sanding in between if the fibres rise (Troedoor, Dutch).
• Wax or wax-oil: gives a warm colour, but wax offers only limited resistance to moisture (Meijs Wonen, Dutch).
• Lacquer: the lowest-maintenance option; lacquered wood only needs wiping with a slightly damp, soft cloth (Meijs Wonen, Dutch).

Steps: clean and degrease the surface, test the product on an inconspicuous spot, apply thinly and follow the drying times on the label.

Used or weathered teak indoors

1. Clean with a suitable wood cleaner.
2. Sand out absorbed stains lightly with very fine sandpaper, along the grain (Meijs Wonen, Dutch).
3. Protect again with the same type of product as the existing finish.

Day to day: wipe up spills straight away, use coasters, and keep the furniture at least 2 metres (about 6½ ft) from a stove, open fire or radiator. Meijs Wonen gives a room temperature of 15 to 24 °C (59 to 75 °F) and a relative humidity of 40 to 60% to limit the “movement” of solid wood (Meijs Wonen, Dutch).

Sideboards, cabinets and bathroom furniture are covered in indoor teak care.

Common mistakes

• Using a pressure washer. Gloster is firm: under no circumstances, because it erodes the soft surface and leaves the wood rough (Gloster).
• A wire brush, stiff brush or steel wool. These remove the softer part of the grain and leave an unwanted textured surface; steel can also leave rust spots in the teak (Gloster).
• Bleach as a cleaner. Gloster warns that it discolours the wood (Gloster).
• Rubbing teak oil into garden furniture “to feed the wood”. See above: risk of mildew and black wood (Gloster, Tribù).
• Sanding across the grain (Gloster).
• Applying sealer to damp or dusty wood. The wood must be 100% dry and free of dust (Gloster).
• Throwing used oil or wax cloths in the bin. Troedoor warns that a cloth with wax-oil on it can ignite by itself: rinse it thoroughly with water or keep it in a closed container (Troedoor, Dutch).
• Moving garden furniture straight into a heated room for the winter. Gloster recommends a dry garden shed or garage; the sharp difference in temperature and humidity can make the wood move too much and split (Gloster).

What isn’t a mistake

A few things look like damage but are normal:

• Fine cracks, especially in the end grain: according to Vincent Sheppard these are normal with changes in temperature and humidity, and do not affect durability or strength (Vincent Sheppard).
• Oil on the surface of new teak: according to Gloster a normal occurrence, and even a sign of high-quality, oil-rich teak (Gloster).
• Teak oil stains on cushions: Tribù calls this a naturally repeating process; the fabric can be cleaned with soap and water (Tribù).
• Wasps stripping grey teak: Gloster describes wasps using the softer grain of weathered teak to build their nests in spring and early summer (Gloster).

In short

• Outdoors, grey is fine: clean once or twice a year with water and a mild detergent, sand lightly if needed, add a colourless protector if you like. No oil.
• Outdoors, keep the colour: clean, let it dry, seal thinly, add a protector on top if you like; repeat at least yearly, table tops in April and October.
• Indoors: choose a finish that suits how the piece is used (protector, impregnating oil, wax-oil or lacquer) and keep moisture and heat away.
• Always: no pressure washer, no wire brush, sand along the grain, test first.