Explaining IRC Residential Building Code Provisions in ESR-2794

The International Residential Code (IRC) Provisions in ESR-2794 include CHANCE® helical pile foundation products. The following is the benefit for our customers:

• Compliance with the Following Codes:  2021, 2018, 2015, 2012 and 2009 International Residential Code^® (IRC) 
• 2.0 USES:  Section 2.2    IRC:  Under the IRC, CHANCE^® Model SS5, SS175, RS2875.203, RS2875.276, RS3500, RS4500 and SS175/RS3500 Combo Helical Foundation Systems may be used as an alternate foundation system supporting light-frame construction, exterior porch deck, elevated walkway and stairway construction and accessory structures.

• 4.0 DESIGN AND INSTALLATION

• Section 4.1.1 General:  Under the IRC, a geotechnical investigation is not required if the helical pile foundation system and devices described in the evaluation report are being installed to support IRC structures defined in Section 2.2 of this Report and,

• The soil capacity of the helical pile system is established in accordance with Equation 5 in Section 4.1.5 of this Report.

• • Section 4.1.5 Soil Capacity (P4):  Under the IRC, when a geotechnical investigation is not available, a safety factor of 2.5 must be used with the torque correlation method to determine the allowable capacity of the helical pile.

Q_ult   =    K_tT               (Equation 3)

Q_all   =    0.4 Q_ult            (Equation 5)

• • 4.3.2 IRC:  Continuous special inspection of helical foundation system and devices installed under the provisions of the IRC defined in this report is not required.

Basically, if your customers are installing new construction or remedial repair foundations for light-frame residential work, then it’s not necessary to have a Geotech Report; nor is it necessary to have continuous special inspection.  This should help contractors get permits/approvals for non-commercial jobs with fewer piles.

Read more about CHANCE helical piles in building codes.