Building Planning

Climatic and Geographic Design Criteria

Section R301.2 — Climatic and Geographic Design Criteria. Buildings shall be constructed in accordance with the provisions of this code as limited by the climatic and geographic design criteria contained in Table R301.2(1). Additional cri...

Wind Design Criteria

Section R301.2.1 — Wind Design Criteria. Buildings and structures shall be constructed to resist the wind speeds given in Figure R301.2(2) as determined from ASCE 7-22. The ultimate design wind speeds range from 110 to 18...

Exterior Walls

Section R302.1 — Exterior Walls. Construction, projections, openings and penetrations of exterior walls of dwellings and accessory buildings shall comply with Table R302.1. Exterior walls with a fire separation di...

Townhouse Separation

Section R302.2 — Townhouse Separation. Each townhouse shall be considered a separate building and shall be separated by fire-resistance-rated wall assemblies. Common walls separating townhouses shall have a fire-resista...

Habitable Rooms

Section R303.1 — Habitable Rooms. All habitable rooms shall be provided with aggregate glazing area of not less than 8 percent of the floor area. Natural ventilation shall be through windows, doors, louvers, or oth...

Glazing

Safety glazing (tempered or laminated) required in hazardous locations: doors, near doors, wet areas, skylights, stairs.

Human Impact Loads

SAFETY GLAZING REQUIRED in hazardous locations per CPSC 16 CFR 1201.

Hazardous Locations

Section R308.4 — Hazardous Locations. The following locations shall be considered hazardous and require safety glazing: glazing in all panels of swinging, sliding, and bifold doors; glazing adjacent to doors within a 2...

Skylights and Sloped Glazing

SKYLIGHT REQUIREMENTS: Must be listed/labeled per AAMA/WDMA/CSA 101. Safety glazing required (tempered, laminated, or approved plastic). ENERGY: Zone 4A max U-factor 0.55, SHGC 0.40. Proper curb construction and flashing critical - use manufacturer flashing kits. Fall protection may be required for low-slope skylights.

Emergency Escape and Rescue Openings

Basements and every sleeping room shall have at least one operable emergency escape and rescue opening. Minimum opening: 5.7 sq ft (5.0 sq ft at grade floor), minimum width 20 inches, minimum height 24 inches. Maximum sill height 44 inches above floor. COLORADO NOTE: Window wells required where egress windows are below grade. Wells must have ladder/steps if over 44 inches deep.

Emergency Escape and Rescue Openings

EGRESS WINDOWS REQUIRED in ALL sleeping rooms. MINIMUMS: 5.7 sq ft net clear opening (5.0 sq ft at grade), 24" height, 20" width, sill max 44" from floor. When replacing windows in bedrooms, new windows must meet egress requirements. Casement and awning windows typically provide better egress than double-hung.

Egress Door

Section R311.2 — Egress Door. Not less than one egress door shall be provided for each dwelling unit. The required egress door shall be side-hinged and shall provide a minimum clear width of 32 inches and minim...

Landings at Doors

DOOR LANDINGS - Required each side of exterior doors. 36" min in direction of travel.

Termite Protection

Section R318.1 — Termite Protection. In areas subject to damage from termites as indicated by Table R301.2(1), methods of protection shall be provided in accordance with this section. Protection shall be provided for ...

Flood Hazard Areas - General

FLOOD ZONE CONSTRUCTION: Verify flood zone on FEMA FIRM maps before construction. Zone A: Lowest floor at/above BFE. Zone V (coastal): Bottom of lowest structural member at/above BFE. Substantial improvement (>50% value) triggers full compliance. Chesapeake Bay and Shenandoah River areas have flood zones. Check with local floodplain administrator.

Wildfire Hazard Mitigation (Local Adoption)

Where adopted by local jurisdiction, construction in designated wildfire hazard zones must comply with fire-resistant requirements. Class A roof assemblies required. Fire-resistant exterior wall coverings. Ember-resistant vents. Tempered glass windows. Defensible space. COLORADO NOTE: Many mountain and foothill communities have adopted WUI codes. Post-Marshall Fire (2021), Boulder County has strictest requirements. Colorado State Forest Service provides defensible space guidance.

General WUI Requirements

Section R327.1 — General WUI Requirements. Buildings and structures located in wildland-urban interface areas as defined by the local jurisdiction or state adoption shall comply with the exterior wildfire exposure protectio...