Ventilation Options were discussed including purposes, methods, controls, standards, and calculations. Residential ventilation is needed for moisture control, odor control, and pollution dilution. Methods include intermittent source control, whole house, supply only, exhaust only, and balanced. Controls can include no controls, timer controls, humidity controls, and temperature controls. Standards discussed were ASHRAE 62.2 and Building Science Corp. Standard 01-2013. Ventilation rates are calculated based on conditioned floor area and number of bedrooms. Intermittent ventilation requires determining required airflow, fractional on-time, and effectiveness. Modeling ventilation correctly in software is important for HERS ratings.

1. Ventilation Options
Brett Dillon
CEO, The Dillon Group, Inc
2015 Midwest Regional Energy Conference

2. About Me
• Trainer
• Quality Assurance Designee
• RESNET Board Executive Committee
Member
• RESNET Standards Management
Board Member
• Chair RESNET/ANSI Standards
Development Committee 300
• Former
• rater
• home builder

3. Why do we need to ventilate homes?
When do we need to ventilate
homes?
How should we ventilate homes?
What ventilation standard should we
use?
Where are these tactics appropriate?
Which software tools are better?

4. What is the purpose of
residential ventilation?

5. Purpose
• Moisture control
• Odor control (?)
• Pollution dilution
• Yankee revenge (?)

6. When do we need to
ventilate a home?

7. Conditional
• What is the occupancy rate?
• What is the climate like?
• What kinds of pollutants are in the home?

8. How should we
ventilate homes?

9. How do we do it?
• intermittent source control
• whole house
• supply only
• exhaust only
• balanced (?)

10. Controls?
• No controls
• Timer controls
• Humidity controls
• Temperature controls
• Humidity & Temperature controls

11. Where are these
appropriate?

12. Where?
• Intermittent source
• Supply only
• Timer control
• Humidity control
• Temperature control
• Exhaust only
• Timer control
• Balanced
• Timer control
• Humidity control
• Temperature control

13. What standard should
we use?

14. Standards
• ASHRAE 62.2-2013
• Building Science Corp. Standard 01-2013
• Legacy standards
• ASHRAE 62.2-1989
• ASHRAE 62.2-2004
• ASHRAE 62.2-2007
• ASHRAE 62.2-2010

15. How do we calculate it?
• ASHRAE 62.2
• Ventilation Rate = (CFA x 0.03) + (7.5 x (Nbr + 1))
• Building Science Corp
• Ventilation Rate = (CFA x 0.01) + (7.5 x (Nbr + 1))

16. How much Ventilation?
ASHRAE 62.2 2004, 2007, 2010
Whole house ventilation
7.5 cfm/person +
1 cfm/100 square ft
Local exhaust
Kitchens > 100 cfm
Bathrooms > 50 cfm
Source control
Test for backdrafting if sum
of 2 largest exhaust fans >
15 cfm/100 sq ft
Air handlers in garage
must be tested for
airtightness
EXEMPT:
Houses in hot climates w/o air
conditioning, houses conditioned < 876
hours/yr, houses in hot dry climates
Mandatory:
Providing local exhaust ventilation to
rooms with unvented combustion
appliances
More Rules:
Unducted range hoods are only permitted
in kitchens w/ a mechanical exhaust
system providing 5 kitchen ACH (cont. or
intermittent)

17. More Rules
• Hot humid climates exhaust limits
• Very cold climates supply limits

18. What about intermittent?
• Required air flow
• Fractional on-time
• Effectiveness

19. ASHRAE 62.2 Required
Airflow
• 1 CFM/100 sf
• 7.5 CFM/person
• Number of
bedrooms plus 1
• Bath, 50 CFM
• Kitchen, 100 CFM
• 2,000 sf, 3 bedroom home
Flow = (2,000 / 100) + (4 x 7.5)
Flow = 20 + 30
Flow = 50 CFM continuous

20. ASHRAE 62.2 Fractional On-
Time
• 1 CFM/100 sf
• 7.5 CFM/person
• Number of
bedrooms plus 1
• Bath, 50 CFM
• Kitchen, 100 CFM
• Daily run time
• 4 hours = 17%
• 6 hours = 25%
• 7 hours, 55 minutes = 33%
• 12 hours = 50%
• 15 hours, 50 minutes = 66%
• 18 hours = 75%
• 19 hours, 55 minutes = 83%
• 22 hours = 92%

21. ASHRAE 62.2 Ventilation
Effectiveness
• 3 hours
• < 35%, 0.33
• 35% - 60%, 0.50
• 60% - 80%, 0.75
• > 80%, 1.0

22. Example
Flow = Required air flow /
(effectiveness x fractional on-time)
Flow = 50 / (1 x 0.25)
Flow = 50 / 0.25
Flow = 200

23. Example
Flow = Required air flow /
(effectiveness x fractional on-time)
Flow = 50 / (0.33 x 0.17)
Flow = 50 / 0.056
Flow = 893

24. Simple Calculator

25. Counting Infiltration

26. How do we model it
correctly?

27. Impact
• RESNET required, 2007
• ENERGY STAR required, 2011
• IRC required, 2012

28. HERS Index Impact
HUGE!

29. HERS Ratings
• Measure the flow rate
• Field measured fan wattage
• Product Data

32. Example:
• Carrier 58STA-110-100-22
• 115 volts
• 11.1 amps
• 115 x 11.1 = 1276.5 watts

33. Example
• Required: 50 CFM continuous
• Measured: 75 CFM intermittent
• Timer setting: 40 minutes
• Hours: 40/60 = 0.67 x 24 = 16
• 16 - 9 = 7 hours additional
• Fan wattage: 1276 watts
• Result: 8.9 kWh/day, 3,248 kWh/yr

34. Which software tools
are better?

35. Software Tools
• RESNET-accredited
• Hourly simulations
• Energy Gauge
• Ekotrope
• Residential Energy Dynamics

36. Questions?

37. Brett Dillon
CEO
www.thedillongroupinc.com
info@thedillongroupinc.com