Teak is durable, but the wrong cleaner or tool can roughen the surface, raise the grain, and leave marks. Most teak only needs gentle cleaning. Gray weathering is usually surface oxidation rather than damage, so it doesn’t call for harsh chemicals. Start with the mildest method, and move to stronger ones only when you need to.
Start gentle
Use warm water, a little mild dish soap, and a soft brush. Scrub along the grain, not across it. Rinse with a low-pressure hose until no soap is left on the wood.
Let the wood dry completely before you seal or oil it. Plan on 24 to 48 hours, depending on the weather.
Clean indoor and veneered teak differently
Indoor teak and veneered pieces need a lighter touch. Don’t soak them. Wipe with a damp cloth, then dry the surface right away. Water can lift the edges of veneer and damage the core beneath. If an edge has already lifted, see how to fix lifting and chipped veneer.
For wax, grime, and old polish, wipe with mineral spirits or naphtha. Ventilate the room well, and wear gloves.
Avoid silicone polishes. They cause fisheye in any finish you apply later, which makes refinishing harder.
Outdoor teak: stronger cleaners, used carefully
Only move to these steps if gentle cleaning hasn’t worked. Test any product on a hidden area first.
Oxygen bleach
Oxygen bleach is the gentler bleach option for mildew and gray staining. A common mix is about 1 cup per gallon of warm water, but ratios vary by product, so follow the label. Scrub gently, let it sit for the time the label gives, and rinse thoroughly.
Chlorine bleach
Chlorine bleach is harsher. Dilute it, and use it only on stubborn mildew. It can roughen the wood, so rinse well and check the surface once it dries.
Two-part teak cleaners
Two-part teak cleaners are strong. They can strip wood fibers, so use them only on heavily weathered teak, and only rarely. Wear gloves and eye protection.
Oxalic acid for stains
Oxalic acid brightens teak. It restores color, removes iron and tannin stains, and neutralizes residue from alkaline cleaners. It is the usual choice for black marks in the wood. Wear gloves and eye protection, and rinse thoroughly afterward.
Raised grain and sanding weathered teak
Once the wood is dry, raised grain can be smoothed with light sanding at the right grit. 120 to 150 grit is usually enough. Badly weathered teak may need coarser paper first, starting at 80 to 120 grit and then moving to 150 to 180 grit.
Sanding removes surface wood, so use it only when cleaning won’t do the job. Don’t sand veneer this way. For veneered pieces, see restoring mid-century teak furniture.
Rinse and dry
Rinse until no cleaner or residue is left. Then let the wood dry for 24 to 48 hours before you oil or seal it. Once it is dry, choose a finish. Teak oil or teak sealer covers the trade-offs.
If cleaning reveals cracks, see how to repair cracks in teak furniture.
What to skip
- Pressure washers. They erode the soft earlywood and leave a ridged, fuzzy surface. A low-pressure hose is safer.
- Steel wool. Iron reacts with teak’s tannins and leaves black spots. Use bronze wool or synthetic pads instead.
- Mixing bleach with ammonia or acid cleaners. Mixing bleach with ammonia releases toxic gas. Use one cleaner at a time, and rinse between products.
- Silicone polishes. They cause fisheye in finishes applied later.
How often to clean and how to cover
Clean outdoor teak about once or twice a year, depending on exposure. If you cover it, use a breathable cover rather than plastic. Plastic traps moisture, which can encourage mildew.
Indoor teak usually only needs dusting and occasional wiping.
Safety
- Wear gloves and eye protection when you use two-part cleaners or oxalic acid.
- Never mix bleach with ammonia or acid cleaners.
- Ventilate the room when you use mineral spirits or naphtha.
- Keep runoff away from plants. Cleaners can harm garden plants and soil.