Insulation and Ventilation

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Improving your home’s insulation is one of the best investments you can make. The initial financial outlay may be quite high, but the long-term savings on heating bills will make it worthwhile. You can insulate most parts of your home against heat loss, and even fairly modest measures can make a big difference. However, efficient thermal insulation must always go hand in hand with effective ventilation to prevent the buildup of condensation and the possibility of mold.

Thermal image of heat loss


Heat flows from warm areas to cold areas, and moves in any direction. In a heated home, warm air expands and circulates, and escapes through walls, ceilings, and the roof, through windows, doors, and fireplaces, and anywhere plumbing, ducting, or electrical wiring penetrates exterior walls. The role of thermal insulation is to reduce the amount of heat that escapes by creating a barrier.

The term “R-value” is used when discussing thermal requirements in a house, especially in conjunction with insulation products. The aim is to achieve high R-values: this means that a house’s insulation is efficient. In a new home, R-values are governed by building codes, and the type of insulation used will therefore need to meet certain requirements.

Thermal image of heat loss

On a thermal image of a house, the roof shows up as cool (blue), suggesting there is insulation present, but the red windows and wooden slats show heat escaping. Even if you have good attic insulation it is important to consider other areas such as walls and windows. If you are installing new windows, they should have double-glazing.

Continue: "Green" Insulation

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