ASHRAE 62.2 Ventilation for Single-Family Dwellings

Before we discuss ventilation, it is important to know why ventilation is important. Do we really need these additional mechanical devices in our homes? Yes. Haven’t we been OK without them for decades? Yes and no. We will address the major contaminants found in our homes, including PM2.5, formaldehyde, acrolein, nitrogen dioxide, and moisture. It is important to keep contaminants out of the house (source control) and manage those that are generated in the house by ventilating and filtering the air.

“Build tight, ventilate right” was first stated in 1992. This statement is not only good rule for the occupants of our dwellings, but it is also good for our houses. We will examine how and why ventilation interacts with natural infiltration by using an online infiltration modeling tool. Descriptions and examples of exhaust-only, supply-only, and balanced ventilation equipment will make you knowledgeable with all ventilation types and their related controls. This topic will clearly show you what your options are.

ASHRAE Standard 62.2, "Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings", was first released in 2002. It has become the most often used standard for ventilation in the U.S. The International Residential Code (2012 and 2015) includes ventilation requirements that are closely aligned with ASHRAE 62.2, but are relatively brief. This week we will address the details of these ventilation standards/codes, stressing ASHRAE 62.2. By the end of the week, you will be familiar with local and whole-building ventilation requirements for new and existing dwellings, both single-family and multifamily.
Additionally we will calculate the minimum ventilation requirements for example dwellings using ASHRAE 62.2 and a few examples for California’s unique version of the 62.2 standard. For these examples, we will use free online tools that will be available during and after this course.

Up to this point we have looked at why ventilation is important, what the basic types of ventilation systems are, what the standards/codes require, and how to size the ventilation fans correctly. This week we will look at how to select fans and controls and how to install them properly for the lowest cost. You will learn about the best fans/HRVs/ERVs (brands and models) and controls (brands and models), effective ductwork and termination installation, and performance testing (airflow measurement methods). This week brings all the previous information together for a great, cost-effective installation that satisfies your customers and minimizes re-works.

Are ventilation systems costly to operate? Most people erroneously perceive they are. This week we will calculate the cost of operating the fan motor(s) and the cost of the conditioned air that is exhausted from a dwelling by the ventilation equipment. The low costs are likely to surprise you. The free online tools used for these calculations will be available to you during and after this course. We will carry these calculations a step further by determining the savings-to-investment ratio for controlling airflow (air sealing and adding ventilation).
Finally, we will discuss changes that are coming to the ASHRAE 62.2 standard in 2016 and after. This knowledge will prepare you for the near future of your ventilation installations.

You'll be asked to apply everything you've learned into a final capstone project: running calculations and doing equipment selection based on the ASHRAE 62.2 Standard.