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Why we need to ventilate the roof cavity.

Recent passive house adaptations on existing houses have focussed on insulation in the home and installing double or triple glazing. In carrying out this work The aspect most misunderstood is the need for continuous ventilation in the home and attic space. In this article we cover the need for attic ventilation.

Ventilating the roof cavity or attic space is crucial for several reasons:

1. Moisture Control:

Proper ventilation helps to reduce moisture buildup in the attic. Moisture can accumulate due to activities inside the house, such as cooking, bathing, or using appliances. Without ventilation, this moisture can lead to mold, mildew, and rot, causing damage to the structure and potentially impacting indoor air quality.

2. Temperature Regulation:

Ventilation helps regulate attic temperature. In hot climates, it prevents the buildup of excessive heat in the attic, which can radiate down into the living spaces, making them hotter and potentially increasing cooling costs. In colder climates, ventilation helps to prevent ice dams by keeping the attic temperature closer to the outside temperature, reducing the risk of snow melting and refreezing on the roof edges.

3. Prolonged Roof Life:

Proper ventilation can extend the life of roofing materials. Excessive heat buildup in the attic can accelerate the degradation of roof shingles or other roofing materials, leading to premature deterioration.

4. Energy Efficiency:

Ventilating the roof cavity can contribute to overall energy efficiency. By keeping the attic temperature closer to the outside temperature, it reduces the workload on heating and cooling systems, potentially lowering energy bills.

5. Improved Air Quality:

Adequate ventilation in the attic helps prevent the buildup of pollutants and volatile organic compounds (VOCs) that could otherwise seep into the living spaces, thereby maintaining better indoor air quality.

Ventilation in the roof cavity should ideally involve a balanced system that allows for proper airflow, typically using a combination of intake vents (usually located along the eaves or soffits) and exhaust vents (such as ridge vents, Whirly vents like pictured, or powered exhaust vents ) to facilitate continuous air movement.

To find the most cost effective way to vent attic cavities reach out to the team at Auckland Skylights Limited #aucklandskylights #winddrivenvents #ventilation #attic #airconditioning

Ref mn architects illustration.



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