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Mechanical ventilation for fresh air and for cooling

Mechanical ventilation has a key role in modern construction, by providing fresh air to air-tight homes. But mechanical ventilation can also be crucial to exhaust stale air, or to prevent moisture, mold and mildew...

Should You Have a Mechanical Ventilation Bath FanSystem?

Uncontrolled ventilation can be a cause of high energy bills, unhealthy air and moisture damage.

Every home should have high-quality exhaust fan in each kitchen and bathroom.

Should you Have a Mechanical Ventilation System?

Air Tight Homes, Leaky Homes & Energy Efficiency

Many people still think that their houses need to “breathe”, which makes little sense and contradicts modern construction, with their high levels of air tightness and insulation.

Air tight homes, leaky homes and energy performance
Air Sealing: Solving Moisture Problems
Passive Houses Guide

HRV ventilator from LennoxWhole-House Mechanical Ventilation Systems: Exhaust, Supply and Balanced Systems

Mechanical ventilation systems vary in their type and complexity, and can be grouped into three classes: exhaust, supply and balanced mechanical ventilation systems.

Exhaust vs. Supply Ventilation Systems
Balanced Ventilation Systems

Mechanical Ventilation: For Your Health's Sake

Air infiltration through gaps and openings in the walls, floors and ceilings, or around windows and doors, is the main source of fresh air in many homes.

But air infiltration is a questionable source of fresh air. Air coming in from attics, crawlspaces or wall cavities carries dust, pollutants, moisture, radon... Mechanical ventilation can solve the problem.

See: Uncontrolled Home Ventilation Vs. Mechanical Ventilation

Kitchen and Bathroom Exhaust Fans

Spot kitchen and bathroom ventilation is very important to prevent moisture damages, mildew and mold; every home should have high quality exhaust fans ducted to the outdoors.

Spot exhaust fans should be properly ducted to the outdoors; exhaust air should not be vented into the attic or any other close space.

Simple Exhaust Kitchen and Bathroom Ventilation



Gabble attic fan (electric)Roof Ventilation May Not Be Effective

Roof ventilation can help keep attic temperatures lower. Just do not overestimate it, and do not increase attic ventilation beyond the necessary.

Attic fans - either electric or solar - are popular, but typically ineffective and in some cases counterproductive. They may consume more energy than they save. There are better ways of dealing with overheated attics.

Increasing the Roof Ventilation
Roof Ventilation Systems Efficiency
Attic Fans Efficiency

Using Mechanical Ventilation to Keep Moisture Out

Consider mechanical ventilation and air movement as a way of controlling moisture; it's important to keep your home's moisture levels low, especially in the winter.

Moisture control is important to keep indoor air healthy and to avoid structural damages in walls, floors or attics.

See: Home Moisture Guide

VentilationUsing Natural Ventilation and Breezes for Cooling and Energy Savings

Natural ventilation and shading strategies are the backbone of natural cooling.

Ventilation & Breezes For Energy Savings

Window fan to bring outside fresh airUsing Ventilation Fans For Cooling in Moderate and Hot Climates

Ventilation fans are intended to bring breezes in, during the cooler parts of the day.

Fans and Air Conditioners
Ventilation, Breezes and Window Fans


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Our Video on Ventilation:




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