The City of Lone Tree has moved from Stage 2 Fire Restrictions to Stage 1 Fire Restrictions, effective August 25, 2026 until further notice.

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Current Adopted Building Codes

Design Criteria

Roof Snow Load – 30psf 

115 ULT – Exposure C 

  • Seismic Design Category: IRC: B 
  • Seismic Design Category: IBC: Per chapter 16 
Condition Value
Heating Degree Days 6343
Winter Design Temperature -3 °F
Summer Dry Bulb 90 °F
Summer Wet Bulb 59 °F
Air Freezing Index 867
Mean Annual Temperature 48.1 °F
Minimum Frost Depth for Foundations 36 inches

IBC table 1607.1 

  • Live load 40psf (30psf in sleeping areas) see table R301.5 
  • Dead Load 10psf 
  • Duration of Load 1.00 
  • Deflection L/360 

Live Load 30psf (attic=”10psf” no storage, 20psf limited storage) 

Dead Load 10psf Minimum or as required based on type of roofing material and ceiling material, see table R301.6 

Duration of Load 1.15 (Snow) 

Deflection L/180 Rafters (no ceiling); L/240 (ceiling); L /240 Beams, see table R301.7 

RESIDENTIAL EXTERIOR DECKS: 40psf Live Load (LL), see table R301.5 

COMMERCIAL EXTERIOR DECKS: see table 1607.1