Sunday, February 26, 2017
 
   
RED Calc Free Help ASHRAE 62.2-2013
ASHRAE 62.2-2013 Tool User Guide

ASHRAE 62.2-2013
Red Calc Tool User Guide

What this tool can do for you

The ASHRAE 62.2-2013 RED Calc tool handles all the requirements of the Standard, including new and existing buildings, the alternative compliance path, and infiltration credit. We have added useful features, including the advanced blower door inputs option, the fan-run time option for intermittent operation of whole-building ventilation, and the whole-building leakage rate solver.

This tool complies with the requirements of the Building Performance Institute (BPI), so you can use it with confidence.

_ALT_TEXT_
ASHRAE 62.2-2013

Calculated values

  • Effective annual avg. infiltration rate.
  • Whole-building Total required ventilation rate, Qtot.
  • Alternative compliance supplement.
  • Infiltration credit, Qinf.
  • Whole-building Required mechanical ventilation rate, Qfan.
  • Fan run-time per hour.
  • Corresponding building leakage for a chosen whole-building ventilation rate.

ASHRAE 62.2-2013 video tutorials

Tips

  • Clicking the label for any input or result will cause a popup help box to appear. This help box includes the allowed and normal values (for inputs). Read more.
  • Weather data is included for the United States and Canada. The weather data for the 2013 tool includes 1100 locations in North America, whereas the 2010 version included less than 300.
  • As an aid in finding the closest weather station location, use the Weather Station Data RED Calc Free tool. Select the "Show map" check box to select the closest weather station on the Google map.
  • You may choose to use the Advanced Blower Door Inputs to adjust your results for temperature, altitude, and pressure exponent.
  • You may choose to use the Local Ventilation Alternative Compliance feature for existing dwellings. This feature includes one kitchen and from one to five bathrooms. This option may not be used for new buildings.
    • When you enter the measured "Fan Flow" in the "Use Local Alternative Compliance", make sure enter the flow rates for the fans that will be in place when the job is completed. If an existing fan is left in place, its flow should be entered.
    • If an existing fan is replaced, the flow rate of the new fan must comply with the ASHRAE 62.2 local fan requirements. You may enter the flow rate of this new fan; the proper calculations will be done.
    • If a new kitchen or bathroom fan is installed where there was no fan previously, the flow rate of the new fan must comply with the ASHRAE 62.2 local fan requirements. You may enter the flow rate of this new fan; the proper calculations will be done.
  • For new construction, the infiltration credit is limited to 2/3 of the Total required ventilation rate, Qtot. The RED Calc Free 62.2-2013 Ventilation tool automatically calculates this limit for you. The existing building infiltration credit is not limited by this 2/3 rule.
  • For multifamily dwellings in buildings of three stories or fewer above grade, refer to the "Multifamily Dwellings" section below.
  • The Whole-Bldg Ventilation Run-Time Solver allows you to determine run-time per hour if you wish to operate the whole-building fan intermittently.
  • The Whole-Bldg Leakage Rate Solver allows you to determine the building leakage rate at 50 pascals that corresponds to a chosen whole-building mechanical ventilation rate.
  • The ASHRAE 62.2 Standard is written as a minimum standard; you may exceed the minimum requirements of the Standard.

Inputs and field measurements

  • Foor area - from site measurement or construction drawings. This area is defined as all enclosed above- and below-grade finished areas suitable for year-round use. Include basements, or parts thereof, only if they are finished in a manner similar to the rest of the dwelling.
  • Number of occupants - the number of bedrooms, plus one. For variation, see ASHRAE 62.2-2013, Section 4.1.3.
  • Building height - from site measurement or construction drawings. The Standard defines this as "vertical distance between the lowest and highest above-grade points within the pressure boundary, ft (m)".
  • Measured leakage - from single-point or multi-point blower door test.
  • Advanced blower door inputs - optional; indoor temperature, outdoor temperature, altitude, and pressure exponent.
  • Local ventilation alternative compliance - optional; measured fan flow in kitchen and up to five bathrooms, openable windows in kitchen and up to five bathrooms. May be used for existing dwellings only.
  • Fan capacity - optional; the capacity of the fan you will install (or the fan that is already installed) that you will automatically control to operate intermittently. This value must be at least the Required mechanical ventilation rate, Qfan.
  • Whole-building ventilation rate - optional; a whole-building mechanical ventilation rate for which you want to determine the corresponding building leakage rate at 50 pascals.

Background

Although the first version of the ASHRAE Standard 62.2, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings, was published in 2003; the 2010 version was the first to gain national attention.

The Wisconsin low-income weatherization program was the first organization to adopt the residential ventilation/IAQ standard, in late 2004. As of the end of 2012, they had installed ASHRAE 62.2 ventilation in over 20,000 homes.

The adoption of the ventilation/IAQ standard gained momentum in 2011 when the Department of Energy required the use of ASHRAE 62.2-2010 in the low-income weatherization program by the end of the 2012 program year. In 2013 the Building Performance Institute (BPI) adopted the 2013 version of the standard.

The adoption of ASHRAE 62.2 makes obsolete the use of the Building Tightness Limit (BTL or BTLa), the Building Airflow Standard (BAS), and the Minimum Ventilation Rate (MVR). These methods were based on the obsolete ASHRAE 62-1989 standard.

Best practices

  • In order to use the infiltration credit for a new dwelling, you must conduct a blower door test. The appropriate sequence to use for a new building is as follows: First, you must estimate what you think the blower door test value will be when the dwelling is completed. Second, install a whole-building fan with a capacity that exceeds your estimate for the final airflow rate. Third, conduct the blower door test when the dwelling is finished. Finally, adjust the whole-building ventilation fan airflow rate with a variable-speed control to satisfy the actual whole-building airflow rate, Qfan.
  • Regarding the infiltration credit and the required blower door testing, ASHRAE 62.2-2013 Standard states: "Effective Annual Average Infiltration Rate (Qinf) shall be calculated using the normalized leakage calculated from measurements of envelope leakage using either ASTM E779 or CGSB 149.10. The authority having jurisdiction may approve other means of calculating effective leakage area (ELA), such as the RESNET Mortgage industry National Home Energy Systems Standard." (ASHRAE 62.2-2013, Section 4.1.2). Both ASTM E779 and CGSB 149.10 require multi-point blower door tests.

    The above statement from ASHRAE 62.2-2013, Section 4.1.2, requires a multi-point blower door test for compliance with the Standard, "unless the authority having jurisdiction [approves] another means of calculating effective leakage area (ELA). . ." In other words, when using the infiltration credit, you are not in compliance with the Standard unless you do a multi-point blower door test, unless your "authority having jurisdiction" allows you to use a single-point test. So, keep in mind that a single-point test is not best practice, and, unless you have approval, it is not in compliance with the Standard.
  • The ASHRAE 62.2-2013 Standard allows the use of the alternative compliance path (Appendix A of the Standard) for existing dwellings. This path allows compensation for deficits in local ventilation (kitchens and bathrooms) by increasing the flow rate of whole-building ventilation. Generally, use of this alternative path saves installation time and money, but it might result in lower indoor air quality. Whenever possible, avoid the use of the alternative compliance path and install separate local and whole-building ventilation fans.

Multifamily Dwellings

The 2013 version of the ASHRAE 62.2 Standard includes a significant section for multifamily buildings (the Standard addresses multifamily buildings of three stories or fewer above grade). In order to use the RED Calc Free 62.2-2013 tool for multifamily dwelling units, follow these procedures:

     New Buildings:
  • For "New or existing construction", select "New".
  • For "Use infiltration credit", select "No". The 62.2-2013 Standard does not allow the use of the infiltration credit for multifamily dwellings.
  • For other tool inputs, enter values as you would normally.
     Existing Buildings:
  • For "New or existing construction", select "Existing".
  • For "Use infiltration credit", select "No". The 62.2-02013 Standard does not allow the use of the infiltration credit for multifamily dwellings.
  • For "Use Local Ventilation Alternative Compliance", check this box if you wish to use this path of compliance, leave it unchecked if you do not. If you use this compliance path, enter the inputs as you normally would for a single-family dwelling.
  • For other tool inputs, enter values as you would normally.

References

  • ASHRAE. ASHRAE Standard 62.2-2013: Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. This document may be purchased at www.ashrae.org.
    Comment: This is the official standard upon witch the RED Calc tool is based.
  • ASHRAE. 62.2 User's Manual. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. This document may be purchased at www.ashrae.org.
    Comment: This document is based on ASHRAE 62.2-2010 and includes many explanations and examples for field use.
  • ASHRAE. ASHRAE Guideline 24: Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. This document may be purchased at www.ashrae.org.
    Comment: This document is loosely based on ASHRAE 62.2-2013 and includes commentary and guidance on achieving acceptable indoor air quality in low-rise residential buildings.
  • ANSI/ASTM E799-10. Standard Test Method for Determining Air Leakage Rate by Fan Pressurization. ASTM International, West Conshohocken, PA.
    Comment: This blower door testing protocol is cited in ASHRAE 62.2-2013, Section 4.1.2.
  • CAN/CGSB 149.10-M86. Determination for the Airtightness of Building Envelopes by the Fan Depressurization Method. Canadian General Standard Board, Gatineau, Quebec, Canada.
    Comment: This blower door testing protocol is cited in ASHRAE 62.2-2013, Section 4.1.2.
  • Raymer, Paul H. Residential Ventilation Handbook: Ventilation to Improve Indoor Air Quality. New York: McGraw Hill, 2010
    Comment: This is a very usable resource for the understanding and installation of residential ventilation. Includes many good illustrations, tables, and charts.
  • RESNET. (2011). Mortgage industry National Home Energy Systems Standard. Residential Energy Services Network.
    Comment: This blower door testing protocol is cited in ASHRAE 62.2-2013, Section 4.1.2.
  • Sherman, M.H. (2004). ASHRAE's First Residential Ventilation Standard. Lawrence Berkeley National Laboratory, Berkeley, CA. LBNL-42975R3.
    Comment: This is the best background resource for the ASHRAE 62.2 residential ventilation standard.
  • Walker, Iain and Max Sherman. (2008). Energy Implications of Meeting ASHRAE Standard 62.2. ASHRAE Transactions, Vol. 114, Part 2.
    Comment: Good resource for the implications of energy use when complying with the ASHRAE 62.2 Standard.

Related tools

  • Weather Station Data (TMY): The embedded Google map feature helps you find the closest (TMY) weather station when your location is close to a state/province or national border and the closest station is actually in a different state/province/country. Additionally, the tool's interactive table and chart help you explore the the Typical Meteorological Year (TMY) data for each of 1,100 weather stations in North America. This is the same data used by the ASHRAE 62.2-2013 tool.
  • ASHRAE 62.2-2010 Ventilation: Determine whole-building ventilation requirements for new and existing dwellings, with the choice of using advanced blower door options and the alternative compliance path.
  • Ventilation Electrical Usage: Determine the annual electrical cost of operating a ventilation fan that is set up for continuous or intermittent use.
  • Depressurization Analysis: With this "solve-all" tool you can calculate house pressure, CFM50 tightness limit (Depressurization Tightness Limit), or total exhaust fan flow.
  • Pitot Tube Airflow: With this tool, a pitot tube, and a digital manometer, you can determine the airflow of a ducted range hood, a clothes dryer, or other appliance will an accessible duct.
  • Box Airflow: Determine the flow of an exhaust fan with this tool, a cardboard box, and your digital manometer.

Version 2016-07-06_01:30
© 2014 Residential Energy Dynamics, LLC

Home   |   About Us
Copyright 2016 Residential Energy Dynamics, LLC