Do you need a dehumidifier at home in Singapore?

Signs your home is too damp

Does a Singapore home need a dehumidifier? Many do not. A flat with windows on two sides and a steady breeze often copes with the humid air on its own. You have a stronger case for buying one when the same room shows the same signs week after week:

• A musty smell that returns within hours of airing the room.
• Grey or black specks on ceiling corners, wardrobe backs, bags or shoes.
• Shirts that still feel damp after a full day on an indoor rack.
• Water beads on windows, mirrors or a cold wall in the morning.

The damp room Singapore households mention most often is a bedroom kept shut all day while everyone is at work. Another is a household shelter used as a storeroom, with its heavy door and no window. One musty week after heavy rain is not a pattern. A smell that never leaves is.

If spots have already appeared, start with the mould FAQ. This post sticks to the dehumidifier itself.

Fix the cause first

A dehumidifier pulls water out of the air. It cannot stop water coming through a wall. If a ceiling patch darkens after your upstairs neighbour showers, or paint bubbles beside the bathroom, suspect seepage. The tank will keep filling while the wall stays wet. Read up on water seepage on walls and have the source traced first.

Airflow comes next. The National Environment Agency (NEA) says occupants of residential homes may improve home ventilation by opening doors and windows, and that fans can be used to promote air circulation when needed. In a damp bedroom, that might mean opening the windows each morning and leaving a fan running for an hour.

Exhaust fans do the same job in wet areas. Run the bathroom fan during a shower and for a while after. Keep the bathroom door shut so the steam leaves through the fan instead of drifting into the bedroom.

If the room still smells musty after a couple of weeks, consider a dehumidifier.

Dehumidifier Singapore guide: where it helps and what to choose

A dehumidifier works well in rooms you can close: a bedroom, a walk-in wardrobe, the household shelter, or a condo study where laundry hangs on wet days. In a landed home, a ground-floor room or the store under the stairs can be the dampest spot.

When comparing models, look at three things:

• Capacity. Makers rate how much water a unit removes in a day and suggest a room size. Match it to the room you will use, not the whole flat.
• Tank or hose. You empty a tank by hand. A model with a continuous drain outlet can run a hose to a floor trap, which suits a service yard or a room next to the bathroom.
• Tank-full cut-off and noise. Check that it stops when the tank is full, and look at the maker's noise details if it will run in a bedroom.

Ventilate first, then shut the door and windows while it runs. Otherwise it is trying to dry the outdoors. Clean the filter as the manual says. For laundry habits, see clothes not drying indoors.

Aircon dry mode vs dehumidifier

Many split aircons have a dry mode. It runs the indoor unit to take moisture out of the room, and the water leaves through the aircon's drain pipe, so there is no tank to empty. The catch is reach: it only works in a room with an indoor unit, and only while the aircon is on.

You can wheel a dehumidifier into a household shelter, a wardrobe room or a guest room with no aircon and leave it there for a few days.

For settings that use less power, see aircon settings that save electricity.

Safe use

The Consumer Product Safety Office advises following the appliance's installation and user manuals and keeping liquids away from sockets. Stand the unit on a flat, firm floor where a full tank cannot tip, and route any drain hose away from power points.

The Energy Market Authority (EMA) advises against using appliances with damaged or exposed cables and against overloading circuits with multi-plugs. It also asks you to look for the SAFETY Mark. Plug the dehumidifier straight into a wall socket, and read our Safety Mark post before you buy.

If the nearest socket is in the wrong place, EMA says shifting or extending an electrical point needs a Licensed Electrical Worker (LEW), who must also apply to SP Services to inspect the completed work.

Behind wardrobes and in storerooms

A dehumidifier in the middle of a bedroom dries the air you breathe, but the narrow gap behind a wardrobe on an outside wall can stay damp. Leave a little space behind freestanding wardrobes and open the doors for a while each day. If spots appear on the back panel, see mould behind the wardrobe. In a storeroom, run the unit with the door shut, then open the door to air the room and empty the tank. A handyman can help move heavy furniture, and quotes depend on the job.

Questions