Monday, April 14, 2008

The Importance of Ventilation in Structural Insulated Panel Homes

How important is ventilation in a structural insulated panel (SIPs) home?

When considering the use of structural insulated panels (SIPs) for the construction of your new green home, proper mechanical ventilation is required. Ventilation systems provide fresh air circulation throughout the building and exhaust moisture laden and stale air outside.

SIPs create an air-tight and extremely energy efficient building insulation system offering a continuous R-Value throughout the building. Air from outside cannot infiltrate the walls of a SIPs home; therefore, reliance on mechanical ventilation is needed in order to ensure a fresh and abundant supply of healthy air. Maintaining appropriate indoor humidity levels, filtering the air for allergens and air humidification/dehumidification is achieved through a couple of technologies.

An air-to-air exchanger, also called a heat recovery ventilator (HRV) or energy recovery ventilator (ERV), is most often used to achieve better indoor air quality. The area of the country in which you build your new SIPs, timber frame, or post and beam home will dictate whether an HRV or an ERV system will be installed.

During the air exchange process, fresh, incoming air is either preheated or cooled with outgoing stale air; the two airstreams intersect through the heat exchanger allowing much of the heating or cooling energy to be recovered on the inside of the home.

With the use of SIPs smaller, ‘right-sized’ HVAC equipment may be installed, and the HVAC contractor would install the air exchange systems. HRVs/ERVs are typically sized to ventilate the whole house at a minimum of .35 air changes per hour. In order to calculate the size of the system needed, the square footage of the house (including basement) is multiplied by the height of the ceiling to get the cubic volume, divide by 60 and multiply by .35. It is always important to consult local codes for exact sizing requirements.

For more information about integrating an HRV or ERV system, please visit

Kimberly Bonin
Executive Project Manager
Bonin Architects & Associates

No comments: