(Photo: Silvia Marks, Deutsche Presse-Agentur)

Water is the worst enemy of wooden furniture. Use too much when cleaning, and you'll cause the wood fibres to swell and the surfaces to change shape.

Here're some tips on how to look after your wooden furniture.

VARNISHED

Varnish helps protect wood against moisture and dirt, making it particularly easy to care for. A quick wipe with a damp cloth is enough, says Mareike Hermann from the German DIY Academy. "You don't need to use much water."

Microfibre cloths are not recommended, as particles can get trapped in them and cause scratches. Hermann's advice? "Use an old T-shirt or cotton bedsheet."

The following also applies to all wood surfaces: "Only use products recommended by the manufacturer," says Andreas Ruf from the Pro Solid Wood Initiative. "We advise against using commercially available cleaners as they can contain substances that harm the wood."

Small stains or discolouring can often be removed with a non-aggressive detergent or some lighter fluid.

"If this doesn't work out or if the damage is larger, the varnish has to be sanded down and revarnished," says DIY expert Hermann. Small scratches or dents can be filled with hard or soft wax. Very fine scratches or marks disappear with an abrasive pencil in the right shade.

GLAZE PAINTED AND OILED

You should never let water near furniture that's been treated with oil or a glaze. "A soft, dry, lint-free cloth is best," says Hermann. "A soft brush or a soft vacuum cleaner nozzle are also suitable."

Severe damage such as traces of frequent touching can be rubbed off with abrasive fabric, explains Ruf. "This removes the upper layer of oil or wax, which usually contains the dirt."

"To get rid of deeper scratches or dents, you'll need to sand the furniture down," adds Ruf. Wipe the damaged area with a damp cloth, then use an iron on a low setting. Finally apply a new layer of oil or glaze.

UNTREATED

Natural surfaces will crack and dry when not treated properly. Water can be used here. "Untreated furniture can be rubbed down with a damp sponge and a mild natural soap," explains Hermann. It is important to dry the furniture afterwards.

Scratches and stains can be removed relatively easily by sanding the furniture down. However, it's best to avoid damage in the first place. "Always place a coaster underneath glasses, vases and flowerpots," says Hermann.

VENEERED

Veneered furniture can be treated just like solid wood, depending on whether it is varnished, glazed or oiled. "Veneer is extremely sensitive," explains Ursula Geismann from the Veneer + Nature Initiative.

Veneer is thin sheets of wood, 0.3 to 6 millimetres thick, glued onto a base material such as chipboard or plywood. Water, heat and soap are poison for these thin woods. "Too much moisture and the veneer will swell and the thin layers peel away," Geismann explains. "If this happens, call a specialist."

Written by Katja Fischer for Deutsche Presse-Agentur