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RED Calc Pro Tools

Current RED Calc Pro Tools

Ventilation

  • ASHRAE 62.2-2019
  • ASHRAE 62.2-2016
  • ASHRAE 62.2-2013
  • ASHRAE 62.2-2010

Airflow Measurement

  • ACH50
  • Air Leakage Metrics
  • Box Airflow
  • Depressurization
  • ZPD

Insulation

  • Dense-Pack
  • Infrared R-Value
  • Loose-Fill

Moisture

  • Moisture Metrics
  • Wood Moisture

DHW

  • Volume per Use

Electrical Use

  • Electrical Usage

Notes

  • Add custom notes to folders

These RED Calc Pro tools calculate dwelling-unit ventilation based on the ASHRAE 62.2 Standard, Ventilation and Acceptable Indoor Air Quality in Residential Buildings, which is updated by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) every three years. When used correctly, these RED tools comply in all instances with the 62.2 Standard. 

Cover of ASHRAE 62.2-2016

Note: Add screenshots of mobile to show mobile friendly

ASHRAE 62.2-2019
Calculates the required minimum flow rate of dwelling-unit ventilation. Complies with ASHRAE 62.2-2019, including Alternative Compliance Path, superposition, fan run-time, and leakage-rate solver. Scope includes detached dwellings and dwelling units in multifamily buildings of any height. See User Guide.

RED Calc Pro ASHRAE 62.2-2019 tool screenshot. Not all features of the tool are expanded in this view.
RED Calc Pro ASHRAE 62.2-2019 tool PDF of report. Unexplanded sections of the tool are not included in this report.

ASHRAE 62.2-2016
Calculates the required minimum flow rate of dwelling-unit ventilation. Complies with ASHRAE 62.2-2016, including Alternative Compliance Path, fan run-time, and leakage-rate solver. Scope includes detached dwellings and dwelling units in multifamily buildings of any height. See Tool Guide.

ASHRAE 62.2-2013
Calculates the required minimum flow rate of dwelling-unit ventilation. Complies with ASHRAE 62.2-2013, including Alternative Compliance Path, fan run-time, and leakage-rate solver. Scope includes detached dwellings and dwelling units in multifamily buildings of three stories or less. See Tool Guide.

ASHRAE 62.2-2010
Calculates the required minimum flow rate of dwelling-unit ventilation. Complies with ASHRAE 62.2-2010, including Alternative Compliance Path, and fan run-time. Scope includes detached dwellings and dwelling units in multifamily buildings of three stories or less. See Tool Guide.

Airflow Measurement

This group of RED Calc Pro tools calculates two important and broad categories of building science: Air measurement, including air flow in a duct, and air leakage, including ACH50 and Equivalent Leakage Area. As our residential buildings become tighter as a result of efforts to save energy and curb global climate change, this data becomes more important.

ACH50
Calculates hourly (low, average, and high) stack, wind, and total infiltration; the effect of combining whole-building ventilation and natural infiltration; and the load on heating and/or cooling systems due to ventilation and infiltration. Additionally, three separate charts provide graphical representations of these results. All calculations are based on TMY3 weather data and may be set to a specific date range (one day to one year). See Tool Guide.

ZPD illustration
ZPD testing to attic

Air Leakage Metrics
Calculates all the useful air leakage metrics. Enter one of eight Air Leakage Metrics to solve for seven others. You choose which to solve with this “solve-all” tool. Includes leakage at 50Pa, ACH50, Equivalent Leakage Area (ELA), Effective Leakage Area (EqLA), Specific leakage area, Leakage at 50Pa/floor area, Leakage at 50Pa /surface area, and Leakage coefficient. See Tool Guide.

Box Airflow Measurement
Calculates required exhaust airflow rate with your custom-made box and a digital manometer. The size of the box may vary. See Tool Guide.

Depressurization
Calculates Depressurization Tightness Limit (DTL) CFM50, the maximum exhaust appliance airflow rate for a given DTL or house pressure, and the negative pressure threshold for a given DTL and appliance airflow rate. This is a “solve-all” tool, meaning you can solve for all or most of the tool variables by checking the radio button to the left of the variable name. See Tool Guide.

Pitot Tube Airflow Measurement [Coming Soon]
Calculates airflow rate in supply or return duct. With a pitot tube and a digital manometer (pressure gauge), you can calculate duct airflow by inserting your pitot tube through the side of the duct into the air stream. This tool allows for adjustment to altitude, duct air temperature, and pitot tube K-factor. The tool includes a calculator for the cross-sectional area of the duct, whether rectangular, round, or oval. See Tool Guide.

Zone Pressure Diagnostics (ZPD)
Calculates air leakage through and leakage area in the interior and exterior pressure boundaries of a zone. Find the zone’s contribution to whole-house leakage. Appraise the effectiveness of your air sealing work, and much more. Simply the best ZPD tool ever! No need to measure openings, hole and door methods combined and accuracy is reported. See Tool Guide.

Insulation and R-Value

This bundle of RED Calc Pro includes tools for determining R-Value, the number of bags of insulation, the density of insulation, and more. 

Dense-Pack Insulation
Calculates installed density or the number of bags of insulation. This tool will work of any dense-pack insulation and accommodates hidden or exposed framing in ceiling, walls, and floors. See Tool Guide.

House drilled for cellulose
Dense-packing walls

Infrared R-Value
This tool calculates R-value or interior surface temperature with your infrared measurement device (infrared camera or thermometer). This is a great tool for determining if a wall is insulated or not and, if it is, what the effective R-value is. See Tool Guide.

Loose-Fill Insulation
Calculates installed depth, settled depth, settled R-value, or the number of bags of insulation when installing loose-fill cellulose or fiberglass. This tool works best for open-joist attic insulation. See Tool Guide.

Moisture

This group of RED Calc Pro tools includes all you need for analyzing moisture issues in buildings, including dew point temperatures, vapor pressure, humidity ratios, and much more.

Moisture Metrics
Calculates dry-bulb temperature, saturation (equilibrium) vapor pressure, relative humidity, dew point temperature, water vapor density, vapor pressure, wet-bulb temperature, and humidity ratio. See Tool Guide.

Psychrometric_Chart_BSI023
Psychrometric chart (BSC)

Wood Moisture
Calculates relative humidity or wood Equilibrium Moisure Content (EMC). Enter the air temperature and equilibrium moisture content of a sample piece of wood that has been in the space. The RED tool will calculate the average relative humidity for you. Or enter the air temperature and the EMC to find the average relative humidity. See Tool Guide.

Domestic Hot Water (DHW)

These tools help you analyze hot water use, allow you to compare hot water systems, and guide you through the procedure of determining flow rate from a fixture.

DHW Volume per Use
Calculates the volume of hot water used given an amount of mixed (hot + cold) water used and the temperatures of the hot, cold, and mixed water. The amount of mixed water can be specified by volume directly, or from a flow rate and duration. See Tool Guide.

water heater in basement energystar
Heat pump water heater

Electrical Usage

If you need to determine the cost of operating an electrical device, this tool will help you.

Electrical Usage

Self-actuating light bulb

Notes

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Notes
Calculates the electrical cost of operating a ventilation fan (or another electrical device) for a year (or another period). This tool will work for continuous or intermittent operation of a fan. See Tool Guide.

IECCmap-2015
U.S. climate zone map

Getting Started with RED Calc Pro

Finding Tools and Tool Guides

Navigate to any RED Calc Pro tool or Tool Guide using the slide-out menu icons on the left side of the screen. style=”text-align: left;”> Click the red menu button to the left for the RED Calc Pro tool menu. Click the blue menu button to the left for the Tool Guides.

Supported Browsers

The advanced features of RED Calc Free will run on most versions of these web browsers:

  • Chrome
  • Safari
  • Opera
  • Firefox
  • Edge
  • Internet Explorer (version 8 or higher)