Grease, smoke from cooking or steamy bathrooms can be removed by use of exhaust fan. Exhaust fans can be mounted in windows walls and ceiling. Also available in combination with lighting, heating or both.

Ventilation has two main purposes. The one we usually think of is letting cool air circulate around the house in summer. The second purpose is even more vital in structural terms to ensure that moisture does not build up inside the house causing condensation and dampness.

Ventilation can be as simple as a few vents leading from the outside of the house to the area under the floor. If possible, cross-ventilation should be provided to ensure good circulation of air under the house from all angles. If cross-ventilation is not possible, say in a terrace house or attached property, then what under-floor ventilation you can provide needs to be as efficient as possible. In many older houses, the under-floor vents have become blocked, or are inadequate. Make sure they are kept clear so air can get in under the house. If the vents are too small, have a builder enlarge them for you or do the job yourself if you feel competent. The enlarged vents must be supported across the top to prevent the bricks caving in.

Anywhere in the house where moisture could be a problem needs good ventilation. The main areas usually causing concern are laundry, kitchen and bathroom.

Bathroom.
Ideally a bathroom should have a window that is about 15 percent as large as the total floor area Otherwise, provide a properly vented exhaust fan.

Laundry.
Moisture can build up quickly on this area, especially if an electric dryer is not vented to the outside. Plenty of open windows and an exhaust fan should overcome most problems of excess moisture in a laundry.

Kitchen.
Without adequate ventilation, you get a build-up of grease, impurities and odour in a kitchen. Installing a range hood over your stove helps overcome many problems. There are two types of range hood: ducted and ductless. The ducted type vents impurities to the outside air, while the ductless hood has a fan and filter, which traps contaminants and recycles the air. Ideally, the fan should change the air about 15 times an hour. Make sure the filter is kept clean of grease by cleaning it regularly.