ASHRAE 62.2 for Retrofits Ventilation for the 21 st Century Build it - - PowerPoint PPT Presentation

ASHRAE 62.2 for Retrofits

Ventilation for the 21st Century

Build it Tight, Ventilate it Right

ASHRAE 62.2 For Retrofits

• “The standard

defines…………..”

ASHRAE 62.2 For Retrofits

Applies to…

ASHRAE 62.2 For Retrofits

IAQ is the goal– however…..

ASHRAE 62.2 For Retrofits

Advantages to adopting 62.2:

ASHRAE 62.2 For Retrofits

Disadvantages to adopting 62.2:

ASHRAE 62.2 For Retrofits

• ASHRAE requires two

types of ventilation

ASHRAE 62.2 For Retrofits

• Whole House Ventilation

requirements

62.2 Standard Overview

• Install Whole House Ventilation System
• Run the WHV System continuously
• Install Local Exhaust
• Make Up Air directly from outside
• Clothes Dryers vented to outside
• House to garage sealed including ducts
• Account for the interactions of ventilation

systems and atmospherically vented combustion

Terminology

• Ventilation
• Whole House Ventilation
• Local Ventilation
• CFM
• ACH
• Deficits
• Credits

Calculating The Whole-House Ventilation Requirement

ASHRAE 62.2 For Retrofits

PEMDAS

• Parentheses
• Exponents
• Multiplication
• Division
• Addition
• Subtraction

ASHRAE 62.2 For Retrofits

• Option One Use this Formula

CFM = Floor area x .01 + (# of bedrooms +1) x 7.5

Option Two use the table….

Number of bedrooms Floor Area

0-1 2-3 4-5 6-7 >7

<1500 1501-3000 3001-4500 4501-6000 6001-7500 >7500

30 45 60 75 90 45 60 75 90 105 60 75 90 105 120 75 90 105 120 135 90 105 120 135 150 105 120 135 150 165

The Local (Spot) Ventilation Requirement

ASHRAE 62.2 For Retrofits

ASHRAE 62.2 requires local spot ventilation

ASHRAE 62.2 For Retrofits

Fan Deficit Rule

ASHRAE 62.2 For Retrofits

Fan Deficit Rule

Deficit may not be below zero for any bathroom or kitchen

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft

• 100 cfm
• 50 cfm
• 50 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft

• 100 cfm
• 50 cfm
• 50 cfm

Deficit= 100 + 50 + 50 = 200 cfm 200 / 4 = 50 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft

• 100 cfm
• 50 cfm
• 50 cfm

Deficit= 100 + 50 + 50 = 200 cfm 200 / 4 = 50 cfm Whole house ventilation requirement = 45 ( from table 4.1a) With fan deficit = 45 + 50 = 95 cfm continuous.

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft With window credit

• 100 cfm
• 50 cfm
• 50 cfm

Deficit= 100 + 50 + 50 = 200 cfm 3 operable windows x 20 cfm = 60 cfm 200 cfm – 60 cfm = 140cfm 140 / 4 = 35 cfm Whole house requirement = 45 + 35 = 80 cfm continuous.

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 2: 3 BR, 1500 sqft

• 50 cfm
• 50 cfm
• 20 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 2: 3 BR, 1500 sqft

• 50 cfm
• 50 cfm
• 20 cfm

50 + 50 + 20 = 120 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 2: 3 BR, 1500 sqft

• 50 cfm
• 50 cfm
• 20 cfm

50 + 50 + 20 = 120 cfm 120 / 4 = 30 cfm Whole house requirement: 45 cfm + 30 cfm = 75 cfm continuous

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 2: 3 BR, 1500 sqft With window credit

• 50 cfm
• 50 cfm
• 20 cfm

50 + 50 + 20 = 120 cfm 3 operable windows x 20 cfm = 60 cfm 120 – 60 = 60 cfm 60 / 4 = 15 cfm Whole house requirement: 45 cfm + 15 cfm = 60 cfm continuous

Calculating The Infiltration Credit

ASHRAE 62.2 For Retrofits

ASHRAE 62.2 For Retrofits

Calculating The Infiltration Credit

ASHRAE 62.2 For Retrofits

• Measured Infiltration
• Assumed infiltration
• Infiltration Credit

Calculating The Infiltration Credit

ASHRAE 62.2 For Retrofits

• Measured Infiltration

Calculating The Infiltration Credit

Measured Infiltration = CFM 50 / N

ASHRAE 62.2 For Retrofits

• Assumed infiltration

Calculating The Infiltration Credit

Assumed Infiltration = Floor area x 0.02

ASHRAE 62.2 For Retrofits

• Infiltration Credit

Calculating The Infiltration Credit

Infiltration Credit = ½ (Measured – Assumed)

ASHRAE 62.2 For Retrofits

Calculating The Infiltration Credit Example: 1000 sq ft home located in Olympia, WA Blower door 1600 cfm @ 50 pa 1000 sq ft x .02 = 20 cfm 1600 cfm ÷ 25.6 = 62.5 cfm natural 62.5 cfm – 20 cfm = 42.5 cfm 42.5 cfm ÷ 2 = 21.25 cfm You can reduce your whole house continuous ventilation rate by 21.25 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 1: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1500 x .02 = 30 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 1: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1200 CFM @ 50 1500 x .02 = 30 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 1: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1200 CFM @ 50 1500 x .02 = 30 cfm 1200 cfm ÷ 25.6 = 47 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 1: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1200 CFM @ 50 1500 x .02 = 30 cfm 1200 cfm ÷ 25.6 = 47 cfm 47 cfm – 30 cfm = 17 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 1: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1200 CFM @ 50 1500 x .02 = 30 cfm 1200 cfm ÷ 23 = 52 cfm 47 cfm – 30 cfm = 17 cfm 17 ÷ 2 = 8.5 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 1: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1200 CFM @ 50 1500 x .02 = 30 cfm 1200 cfm ÷ 25.6 = 47 cfm 47 cfm – 30 cfm = 17 cfm 17 ÷ 2 = 8.5 cfm

Required whole house ventilation rate: 45 cfm With ventilation credit: 45 – 8.5 = 36.5

Continuous whole house ventilation rate is 36.5 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 2: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1500 x .02 = 30 cfm 3500 cfm @ 50

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 2: 3BR, 1500 Sqft Located in Olympia, Wa

Existing Kitchen & Bath fans installed 1500 x .02 = 30 cfm 3500 cfm @ 50 3500 cfm ÷ 25.6 = 137 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 2: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1500 x .02 = 30 cfm 3500 cfm @ 50 3500 cfm ÷ 25.6 = 137 cfm 137 cfm – 30 cfm = 107 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Infiltration Credit Example # 2: 3BR, 1500 Sqft Located in Olympia, WA

Existing Kitchen & Bath fans installed 1500 x .02 = 30 cfm 3500 cfm @ 50 3500 cfm ÷ 25.6 = 137 cfm 137 cfm – 30 cfm = 107 cfm 107 ÷ 2 = 53.5 cfm

Required whole house ventilation rate: 45 cfm With ventilation credit: 45 cfm – 53.5 cfm = -8.5 cfm

Continuous whole house ventilation rate is 0.

ASHRAE 62.2 for Retrofits

Alternative Compliance Supplement for Existing Dwellings

Appendix A of 62.2-2010

ASHRAE 62.2 For Retrofits

Alternative Compliance Path

• For existing dwellings only.

ASHRAE 62.2 For Retrofits

Alternative Compliance Path

• For existing dwellings only.
• Provides an alternative method of meeting

Local exhaust requirements in kitchens and bathrooms that do not have existing ventilation as required by ASHRAE 62.2-2010.

ASHRAE 62.2 For Retrofits

Alternative Compliance Path

• For existing fans being used, 62.2 sound and

ducting requirements are not applicable.

• You must measure flow if ratings don’t exist

and duct sizing cannot be verified.

– If you only have a rating at .10 IWC, not .25 IWC, you can reduce the rating at .10 IWC by 25%

ASHRAE 62.2 For Retrofits

Alternative Compliance Path If you cannot measure flow or determine ratings, you must assume a zero flow for the fan.

How do we solve this?

What do we install? Where do we install it?

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft

• 100 cfm
• 50 cfm
• 50 cfm

Deficit= 100 + 50 + 50 = 200 cfm 200 / 4 = 50 cfm

Whole house requirement 45 cfm + 50 = 95 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft Option #1

• 100 cfm

110 cfm fan

• 50 cfm

Deficit= 100 + 50 = 150 cfm 150 / 4 = 37.5 cfm Whole house ventilation requirement = 45 ( from table 4.1a) With fan deficit = 45 + 37.5 = 82.5 cfm continuous. The fan installed must meet 82.5 cfm continuous requirement Add 110 cfm fan

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft Option #2

• 100 cfm

80 cfm fan 80 cfm fan Deficit= 100 cfm 100 / 4 = 25 cfm Whole house ventilation requirement = 45 ( from table 4.1a) With fan deficit = 45 + 25 = 70 cfm continuous. The 70 cfm continuous requirement can come from one or both fans. Install 2- 80 cfm fans

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 1: 3 BR, 1500 sqft Option #3

150 cfm 80 cfm fan 80 cfm fan Deficit= 0 cfm Whole house ventilation requirement = 45 ( from table 4.1a) One or more fans must meet the 45 cfm continuous requirement. Install 150 cfm fan Install 2- 80cfm fans

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 2: 3 BR, 1500 sqft With window credit

• 50 cfm
• 20 cfm
• 50 cfm

Deficit = 50 + 50 + 20 = 120 cfm 3 windows x 20 cfm = 60 cfm 120 – 60 = 60 cfm 60 ÷ 4 = 15 cfm

Whole house ventilation requirement 45 cfm + 15 cfm = 60 cfm

Kitchen Bath Bedroom Bedroom Master Bedroom Master bath

Fan Deficit Rule Example # 2: 3 BR, 1500 sqft With window credit

• 50 cfm
• 20 cfm

Set fan to operate at 52.5 cfm continuous Install an 80 cfm fan in the main bath. 50 + 20 = 70 cfm 2 operable windows x 20 = 40 cfm 70 cfm – 40 cfm = 30 cfm 30 / 4 = 7.5 cfm Install 80 cfm fan Whole house requirement: 45 cfm + 7.5 cfm = 52.5 cfm continuous

ASHRAE 62.2 For Retrofits

Calculating Intermittent Flow Rates

Ventilation sample to illustrate continuous vs. intermittent

• Assumptions (I know it’s not this simple – but keep it simple)

– Pollutant – continuous source every hour same amount added – 1 ach dilutes pollutants by ½ – The 3 homes are the identical except ventilation HOUSE A - Continuous Ventilation – 1 ACH thus 24 air changes in day HOUSE B - Intermittent ventilation 1 – fan is turned on one hour per day with 24 ach (same air exchange as continuous) HOUSE C - Intermittent ventilation 2 – fan is turned on at noon and midnight with 12 ach (same air exchange as continuous

WHAT HOUSE DO YOU WANT TO LIVE IN?

Continuous Ventilation

0.2 0.4 0.6 0.8 1 1.2 1 3 5 7 9 11 13 15 17 19 21 23 Constant Average

Intermittent – on 1 hour per day

11.5 5 10 15 20 25 1 3 5 7 9 11 13 15 17 19 21 23 Intermittent 1 Average

Intermittent – noon and midnight

5.5 2 4 6 8 10 12 1 3 5 7 9 11 13 15 17 19 21 23 intermittent 2 Average

2 4 6 8 10 12 14 House A - Continous House B - Int 1 House C - Int 2 Average Pollutant Level

Example: 1000 sq ft home with 3 bedrooms

ASHRAE 62.2 For Retrofits

40 CFM Continuous needed Intermittent Rate: Fan runs 50% of the time With a cycle time of 1 hour ( fan runs 30 minutes per hour) 40cfm ÷ (0.5 x 1) = 80 cfm

Example: 1000 sq ft home with 3 bedrooms

ASHRAE 62.2 For Retrofits

40 CFM Continuous needed Intermittent Rate: Fan runs 50% of the time With a cycle time of 24 hour ( fan runs 12 hours out of 24) 40cfm ÷ (0.5 x 0.52) = 153 cfm

Prescriptive Duct Sizing

ASHRAE 62.2 For Retrofits

ASHRAE 62.2 For Retrofits

Table 5.3 Prescriptive Duct Sizing

Duct Type Flex Duct Smooth Duct Fan rating CFM@ 0.25 IN WC 80 100 125 80 100 125 Diameter in. Maximum Length 3” X X X X X X 4” 3 X X 35 5 X 5” 70 35 20 135 85 55 6” NL 135 95 NL NL 145 7” and above NL NL NL NL NL NL

This table assumes no elbows. Deduct 15’ of allowable duct length for each elbow. NL = no limit in duct length of this size X = not allowed

ASHRAE 62.2 For Retrofits

Table 5.3 Prescriptive Duct Sizing

Duct Type Flex Duct Smooth Duct Fan rating CFM@ 0.25 IN WC 80 100 125 80 100 125 Diameter in. Maximum Length 3” X X X X X X 4” 3 X X 35 5 X 5” 70 35 20 135 85 55 6” NL 135 95 NL NL 145 7” and above NL NL NL NL NL NL

This table assumes no elbows. Deduct 15’ of allowable duct length for each elbow. NL = no limit in duct length of this size X = not allowed

Flex Duct is Not Allowed

ASHRAE 62.2 For Retrofits

Example: 80 cfm fan with 2 elbows 20 foot duct run Will 4” smooth duct work?

ASHRAE 62.2 For Retrofits

Example: 80 cfm fan with 2 elbows 20 foot duct run Will 4” smooth duct work? No 35’ allowable – 30’ for elbows = 5’ feet

ASHRAE 62.2 For Retrofits

Example: 80 cfm fan with 2 elbows 20 foot duct run Will 5” smooth duct work?

ASHRAE 62.2 For Retrofits

Example: 80 cfm fan with 2 elbows 20 foot duct run Will 5” smooth duct work? Yes 135’ allowable – 30’ for elbows = 105’

ASHRAE 62.2 For Retrofits

Section 6 : Other Requirements

ASHRAE 62.2 For Retrofits

6.1 Adjacent Spaces: Measures shall be taken to minimize air movement across envelope components separating dwelling units from garages, unconditioned crawlspaces, and unconditioned attics. Supply and balanced ventilation systems shall be designed and constructed to provide ventilation air directly from the

• utside.

ASHRAE 62.2 For Retrofits

6.1.1 Multifamily buildings: All doors between dwelling units and common hallways shall be gasketed or made substantially airtight with weather stripping except when the ventilation systems design explicitly requires air transfer air from corridors into units.

ASHRAE 62.2 For Retrofits

6.2 Instructions and Labeling: Information on the ventilation design and/or ventilation systems installed, instructions on their proper operation to meet the requirements of this standard, and instructions detailing required maintenance shall be provided to the owner and the occupant of the

• dwelling. Controls shall be labeled as to their function.

(unless the function is obvious, such as a fan switch)

ASHRAE 62.2 For Retrofits

6.3 Clothes Dryers: Clothes dryers shall be exhausted directly outdoors. Devices which allow exhaust air to be diverted into the indoor space to provide extra heating are not permitted.

ASHRAE 62.2 For Retrofits

6.4 Combustion & Solid Fuel Burning Devices: The standard requires the following.

• That the vent system for all combustion appliances be

properly installed.

• Maximum exhaust flow: The two largest exhaust fans

cannot exceed 15 cfm/ 100 sqft if there are atmospherically vented appliances inside the home.

ASHRAE 62.2 For Retrofits

Section 6.5 Air Tightness Requirements

ASHRAE 62.2 For Retrofits

6.5.1 Garages: When an occupiable space adjoins a garage, all walls, floors and ceilings that separate the garage from the occupiable space must be air sealed. 6.5.2 Duct systems: All duct work outside the conditioned space shall be sealed. If the air handler and/or ducts are located in the garage, the garage door to the outside must be open when the duct leakage is tested.

ASHRAE 62.2 For Retrofits

6.7 Minimum Filtration: Mechanical systems that supply air to an occupiable space through ductwork exceeding 10 feet in length shall be provided with a filter having a designated minimum efficiency of MERV 6 or better.

ASHRAE 62.2 For Retrofits

Recommended Resources: ASHRAE 62.2 - 2010 User Manual ASHRAE Standard 62.2 - 2010 They can be purchased at: www.techstreet.com

ASHRAE 62.2 For Retrofits

All projects completed on or after April 1, 2012 must be compliant with ASHRAE 62.2-2010.

ASHRAE 62.2 For Retrofits

Key Points:

• Don’t oversize fans
• Use the most efficient equipment available.
• Use the most durable equipment available.
• Set the post ventilation rate as low as possible. Utilize the

window credit whenever possible.

• Take ownership of the process.

Questions?

ASHRAE 62.2 For Retrofits