| Condensation will occur on any surface that | | | | 50% through the gables or soffits).MOISTURE |
| is below the dew point of the air in contact | | | | PRODUCED BY VARIOUS HOUSEHOLD |
| with it (temperature at which condensation | | | | |
| will occur at the existing humidity level). | | | | ACTIVITIES FOR A FAMILY OF FOURActivities |
| In most houses in winter, the inner surfaces | | | | Moisture Produced (pounds) (litres) |
| of the windows are the coolest surfaces and | | | | |
| condensation will usually occur there before | | | | Cooking 3 meals a day 2 1.0 litre |
| it appears on other surfaces. It seldom | | | | |
| appears on walls because they are normally | | | | Dishwashing 1 0.5 litre |
| warmer, although occasionally condensation | | | | |
| may occur on cold spots such as nail heads | | | | Bathing |
| and in the corners of outside walls where the | | | | |
| insulation is reduced, or in confined spaces | | | | - shower 5 2.5 litres |
| where the circulation of warm room air is | | | | |
| restricted. In some cases this can lead to | | | | - tub 2 1.0 litre |
| mildew and the growth of mould.When | | | | |
| condensation becomes excessive the moisture | | | | Clothes washing (per week) 4 2.0 litres |
| load must be decreased or the ventilation | | | | |
| rate increased. To reduce the moisture load, | | | | Drying indoors or with unvented dryer (per |
| humidfiers should be shut off, automatic | | | | week) 26 13.0 litres |
| dryers vented outdoors, clothes drying | | | | |
| indoors avoided, and the structure checked | | | | Floor mopping (per 100 sq.ft/) 3 1.5 |
| for other possible moisture sources | | | | litres |
| (ventilation, insulation and moisture | | | | |
| barriers in the attic, basement or | | | | Occupants (family of four per day) 12 6.0 |
| crawlspaces; open cisterns; seepage in the | | | | litresDehumidifiers, depending on the |
| basement etc.)HANDY HINTThoroughly dry a damp | | | | capacity of the model chosen, are typically |
| spot on an exposed foundation | | | | capable of removing 7.5 to 20 litres of water |
| | | | from the air in the house, per 24 hour day. |
| wall or floor with a hair dryer. Tape a 12 | | | | The age, type and style of home will affect |
| inch square of | | | | the degree of moisture retention, and |
| | | | therefore have a bearing on the size of |
| heavy plastic over the spot, and check it in | | | | dehumidifier required.Controlled air |
| one or two | | | | exchange, using an HRV (heat-recovery |
| | | | ventilator) is usually a requirement in newer |
| days. Seepage will cause the underside of | | | | homes, especially those built to R2000 |
| the plastic to | | | | standards. In these homes, uncontrolled |
| | | | infiltration/exfiltration of air is reduced |
| be wet, but condensation will form on the | | | | to almost zero, and therefore moisture will |
| top side!Ventilation is generally the most | | | | quickly accumulate causing condensation on |
| effective means available to the homeowner | | | | windows and other cool surfaces.Copyright Gil |
| for reducing humidity and should be obtained | | | | Strachan - All rights reserved.Gil Strachan |
| by opening windows or operating an exhaust | | | | is a professional home inspector, |
| fan (or the furnace fan) as soon as | | | | representing Electrospec Home Inspection |
| significant window condensation appears.If | | | | Services in east-central Ontario, Canada |
| only a moderate or minimal amount of | | | | since 1994. Visit to learn more about home |
| condensation is experienced, switching the | | | | inspections."The Home Reference Book" |
| fan on a forced-air furnace to the | | | | |
| "continuous" or "summer" setting can help | | | | You can probably find a home inspection for |
| reduce humidity in moist areas, by | | | | a little less than what we ask, but you |
| circulating and blending the air throughout | | | | probably won't find the Home Reference Book. |
| the house.Attic ventilation is normally | | | | A $60 value, this solutions-oriented |
| provided by vent openings totalling | | | | reference tool comes free with every |
| approximately one square foot for every 200 | | | | inspection we perform.It's the first tool you |
| to 300 square feet of ceiling area (not more | | | | should have around the house! |
| than 50% through the roof, and no less than | | | | |