The purpose of ventilation in a building’s ‘envelope’ is to provide fresh air to the inside of thestructure and to dilute any pollutants (internally generated) in order to assure proper indoor air quality (IAQ). A Retrotec blower door is used to measure the air leakage and/or air tightness of building’s envelope. As existing structures in the United States are primarily ventilated through leaks in a building’s shell (i.e.: air infiltration) rather than by a structure’s mechanical ventilation systems, an accurate and detailed understanding of the use of data generated by a blower door is critical.

Just some of the reasons for establishing the proper building tightness are:

• Testing of a residential or commercial structure's indoor air quality for contamination caused by indoor air pollution.
• Detection & correction of uncomfortable drafts caused by cold air leakage
• Reducing energy usage &consumption due to air leakage
• Correcting & altogether avoiding moisture condensation issues

The Retrotec blower door system consists of a powerful fan that is mounted into an exterior door frame. The drawing air out of the structure, the fan creates a negative air pressure inside the building. With the outside air pressure bieng higher, it is then pulled inside the structure through all unsealed cracks & openings. The energy auditor may now use an infrared thermal imaging camera to detect these air infiltrations.

All Retrotec blower door systems come complete with a frame, hoses, a variable speed fan, a panel, a detachable manometer and all pressure gauges.  The panel, frame, gauges and all hoses come in a hard case.  The blower fan comes in a separate hard case, included on select units.

Retrotec calibrated air blower doors and duct blower systems can be used in a variety of types of testing:

• Testing residential houses for air tightness.
• Testing building envelopes including, door & window frames for water tightness & rain infiltration.
• NFPA Clean Agent Retention testing.
• (LEED), HERS, BPI & Resnet as well as Passive House / Passivhaus.
• Conducting building envelope compliance testing for energy efficiency standards, such as those by the Leadership in Energy and Environmental Design.

Professional Weatherization Contractors & Energy Auditors use Retrotec blower doors to answer just some of the following questions:

• How Much Ventilation Does the Air Leakage Supply?
• What is the Construction Quality of the Building Envelope?
• How Tight is the Building?
• Where are the Air Leakage Pathways?
• Is this Building Too Loose?
• When Should Mechanical Ventilation be Considered?
• How Much Energy Does the Air Leakage Lose?
• Is this Building Too Tight?