ICC Code Solutions: International Code Council Solutions

S&P Solutions for the 2012 International Residential / Mechanical Code

Download the S&P PowerPoint on the 2012 IRC - IMC Ventilation Requirements

2012 IRC & IMC Defined

The 2012 International Residential Code (IRC) and International Mechanical Code (IMC) were developed by the International Code Council (ICC). The ICC is dedicated to developing model codes and standards used in the design, build and compliance process to construct safe, sustainable, affordable and resilient structures. Most U.S. communities and many global markets choose the International Codes.

  • The International Residential Code (IRC) is in use or adopted in 49 states, the District of Columbia, Guam, Puerto Rico and the U.S. Virgin Islands.
  • The International Mechanical Code (IMC) is in use or adopted in 46 states, the District of Columbia, NYC, Guam, Puerto Rico and the U.S. Virgin Islands.

Source: International Code Council. Retrieved from http://www.iccsafe.org

2012 IRC Ventilation Requirements and S&P Solutions

The Ventilation Requirements of the IRC are found in Chapter 15: Exhaust Systems. We have provided a brief overview of each section requiring ventilation (for the full code visit www.iccsafe.org):

Section M1502: Clothes Dryer Exhaust

The Code Specifies:

  1. The dryer exhaust MUST terminate to the outside
  2. The MAX. length of the [dryer] exhaust duct is 35 feet from the connection of the outlet terminal

Problem Created by Code:

  1. What if the dryer is NOT located close to the outlet terminal?
  2. What if the duct is longer than 35 feet so elbows are necessary creating complicated duct work? (ref. table 1502.4.4.1)

FACT: When ducting from a dryer to the outlet is long and/or complicated the dryer cannot overcome the static pressure thus reducing efficiency and causing increased or poor drying time.

S&P's Recommended Solution:

  • A Clothes Dryer Booster Fan will help overcome the static pressure created from long and/or complicated duct runs.

PV100X with Current Sensor

Section M1503: Range Hoods

The Code Specifies:

  1. Makeup air is required when system is capable of exhausting 400+ CFM
  2. The rate of makeup air must be (approx.) equal to the exhaust air

S&P's Recommended Solutions:


Section M1507: Mechanical Ventilation

The Code Specifies:

  1. Whole-house ventilation AND Local Exhaust is required.
    Note: There is a common misconception that either Whole-house OR Local Exhaust is required. The IRC 2012 requires that both requirements be met. The Local Exhaust fans do count towards meeting the Whole-house requirement.
  2. Bathroom and toilet air must be exhausted directly to the outdoors and shall not be recirculated within the residence.

Whole-house Ventilation Requirements:

  1. One or more supply or exhaust fans, plus associated ducts and controls
  2. Local exhaust or supply fans contribute to the whole-house ventilation requirement
  3. System must have controls that enable manual override
  4. Outdoor (makeup) air must be provided at a continuous rate (ref. Table 1507.3.3)
    Exception: if you use controls that enable operation for at least 25% of each 4 hour segment you can operate intermittently.
Table 1507.3.3
Floor Area (sq. ft.) # Bedrooms & Required CFM
0-1 2-3 4-5 6-7 > 7
< 1500 30 45 60 75 90
1501-3000 45 60 75 90 105
3001-4500 60 75 90 105 120
4501-6000 75 90 105 120 135
6001-7500 90 105 120 135 150
> 7500 105 120 135 150 165

S&P's Recommended Solutions (Whole-house):

  • GOOD: PC-Premium CHOICE Fan (Exhaust) & TD-MIXVENT (Supply)
  • BETTER: 2 TD-SILENT (1 for Exhaust and 1 for Supply)
  • BEST: TR (ERV) or HR (HRV)

Local Exhaust Ventilation Requirements:

  1. Exhaust the minimum airflow rate based on Table 1507.4:
Area to be exhausted Exhaust Rates
Kitchens 100 CFM intermittent or 5 ACH continuous (based on kitchen volume)
Bathrooms 50 CFM intermittent or 20 CFM continuous

S&P's Recommended Solutions (Local Exhaust):

  • GOOD: PC-Premium CHOICE Fan
  • BEST: TR (ERV) or HR (HRV)

2012 IMC Ventilation Requirements & S&P Solutions

The following sections of the IMC 2012 require ventilations:

  • Section 403.1: Ventilation System
  • Section 403.2: Outdoor Air Required
  • Section 403.3: Min Air Flow Rates
  • Section 403.4: Exhaust Ventilation
  • Section 403.6: Variable Air Volume System Control
  • Section 403.7: Balancing

All IRC 2012 Residential Solutions can be used as IMC 2012 Commercial Solutions!

Section 403.1: Ventilation System

The Code Specifies:

  1. Supply and Return (Exhaust) Air is required
  2. Supply Air must equal amount of Exhaust Air

Section 403.2: Outdoor Air Required

The Code Specifies:

  1. Minimum airflow rate determined by Section 403.3
  2. Must deliver required rate of outdoor airflow to the BREATHING ZONE within each OCCUPIABLE SPACE

Section 403.4: Exhaust Ventilation

The Code Specifies:

  1. Exhaust airflow rate determined by Section 403.3
  2. Exhaust makeup air can be combination of outdoor air, recirculated air and transfer (except as limited by Section 403.2)

Section 404.6: Variable Air Volume System Control

The Code Specifies:

  1. Controls required to regulate the flow of outdoor air
  2. Control system must be designed to maintain the outdoor airflow rate required by Section 403.3

S&P's Recommended Control Solutions:

  • FT622 or FT247 Controls
    Allow S&P fans to run continuously at a low rate
  • Percentage Timers
    S&P offers a number of Percentage Timers to match the fan, ERV or HRV that you choose

Note: All summaries and solutions recommended by S&P are the most common situations and in our opinion the best solutions to meet the standards. Please refer to the entire IRC or IMC 2012 Standards and your local code to ensure you are meeting all requirements.