Design Criteria
This page is intended to provide information necessary for building and structure design within the Town of Truckee. It includes climatic and geographic design criteria required by California Residential Code Table R301-2(1).
Adopted Codes:
Chapter 15 of the Town Municipal Code adopts the latest editions of the California codes. Included are the Town amendments to these adopted codes. Adopted codes include the following:
- 2010 California Building Code
- 2010 California Residential Code
- 2010 California Electrical Code
- 2010 California Mechanical Code
- 2010 California Plumbing Code
- 2010 California Energy Code
- 2010 California Green Building Standards Code
- 1997 Uniform Housing code
- 1997 Uniform Code for the Abatement of Dangerous Building
- 2009 Uniform Solar Energy Code
- 2009 Uniform Swimming Pool, Spa and Hot Tub Code
A copy of these codes is available for review at the Building and Safety Division counter. Copies of codes can be purchased at International Code Council.
Copies are also available for download at Building Standards Commission.
Snow Design:
The entire Town of Truckee is declared a snow area. In accordance with CBC Section 1608.2, snow loads are based on the "Report of Snow Load Study of Truckee Quadrangle Portions of Nevada County, California," by John Webster Brown, dated June 1973, a copy of which is on file in the Building Department.
All structures require engineered plans, thereby eliminating building code references to conventional construction. The Snowload by Subdivision table can be used for various subdivisions within the Town's jurisdiction. Snow load criteria for the Tahoe Donner Subdivision can be obtained by request. Please email or fax requests to cdd@townoftruckee.com or 530-582-7889. Include the property street address or assessor's parcel number, a topographic datum reference elevation and your contact, fax number, email or mailing address.
See Town Municipal Code Sections 15.03.110, 15.03.120 and 15.03.140 for specific snow load design criteria that modify the basic requirements of CBC Chapter 16 and ASCE 7-05.
A roof ice barrier underlayment is required on roofs with a slope of less than 8:12. See Municipal Code Section 15.03.100 for specific requirements.
Wind Design:
The basic wind speed (three second gust) is 95 miles per hour. The importance factor, exposure and topographic features are site and project specific, to be determined by the engineer of record. There is no local historical data documenting structural damage to buildings due to topographic wind speed uplift effects.
Seismic Design:
See CBC Section 1613 and ASCE 7-05, Chapter 11. Use Google map or another source to determine site specific longitude and latitude. Use the USGS website or NEHRP disk to determine S1 and Ss. Buildings are normally designed to seismic design category D.
Flood Hazard Design:
Truckee entered into the National Flood Insurance Program on May 17, 1995 with adoption of an ordinance for management of flood hazard areas.
The latest flood insurance study is dated February 3, 2010. It references the following panel numbers:
06057C0508E 06057C0509E 06057C0528E 06057C0529E 06057C0532E
06057C0533E 06057C0534E 06057C0550E 06057C0551E
Climatic Design Criteria:
The annual mean temperature from the National Climatic Data Center is 42.5º F.
The 100 year return period air freezing index (99%) from the National Climatic Data Center is 1187.
The lowest recorded temperature was -31º F in 1965. There are an average of six days annually with a low temperature of 0º F or lower. Depending upon the specific design application, the recommended winter design temperature should be taken somewhere within this range.
The Town of Truckee is located in Climate Zone 16.
Environmental Design Criteria:
Weathering may require a higher strength concrete or grade of masonry than necessary to satisfy the structural requirements of the code. The weathering index for concrete from the Weathering Probability Map (CRC Figure R301.2(3)) is SEVERE. The grade of masonry units shall be determined from ASTM C34, C55, C62, C73, C90, C129, C145, C216 or C652.For protection against freezing, the minimum foundation depth is 18 inches below 7000 foot elevation, 24 inches for foundations located above 7000 feet. See Municipal Code Section 15.03.150 for further information.
Truckee has a potentially heavy probability for termite infestation (from CRC Figure R301.2(6)). For protection against subterranean termites, CRC Section R318.1 shall be followed.
Soils Report Requirements:
In general a soil or geotechnical engineering report is required for new construction. See our local soils report policy for any exemptions.
A soil bearing pressure of 2000 pounds per square foot may normally be assumed for small projects when a geotechnical engineering report is not needed.