# item.guide
Side-by-Side Comparison Doors & Walls

Door Butt Hinge vs. Door Rough Openings

Comparing 2 standards across 14 specifications. 14 key differences identified.

Comparing:
Door Butt Hinge
Door Rough Openings

Standard door butt hinges under ANSI/BHMA A156.1 standardize hinge leaf dimensions, corner radius mortises, leaf thickness, and screw hole template patterns. Sized in 3.5×3.5" for 1-3/8" residential interior doors, 4.0×4.0" for 1-3/4" solid doors, and 4.5×4.5" for commercial ball-bearing fire doors, hinges maintain standardized spacing along door edges.

View full Door Butt Hinge spec sheet →

Door rough openings are standardized framing openings in wood and steel stud walls engineered to accept pre-hung door frames, shims, and finished jambs. Under standard architectural guidelines, rough opening width is calculated as Nominal Door Width + 2.0 inches, and rough opening height is calculated as Nominal Door Height + 2.5 inches, with standard 36×80" doors accommodating ADA accessibility.

View full Door Rough Openings spec sheet →

Specification Comparison Table

14 Parameters
Parameter / Spec
Governing Standards
ANSI/BHMA A156.1 / SDI-100 / NFPA 80 WDMA I.S. 1-A / ANSI A250.8 / ADA Standards Section 404
3.5" Residential Hinge
3.5 × 3.5" (89 × 89 mm) | Leaf: 0.085" (2.2 mm) | 1-3/8" hollow-core doors —
4.0" Heavy Residential Hinge
4.0 × 4.0" (102 × 102 mm) | Leaf: 0.097" (2.5 mm) | 1-3/4" solid-core entry doors —
4.5" Commercial Hinge
4.5 × 4.5" (114 × 114 mm) | Leaf: 0.134"–0.180" | Ball-bearing fire doors —
Corner Radius Types
Square corner | 1/4" radius (dime size) | 5/8" radius (quarter size) —
Top Hinge Standard Spacing
5.0 inches (127 mm) down from top edge of door to top of hinge —
Bottom Hinge Standard Spacing
10.0 inches (254 mm) up from finished floor to bottom of hinge —
Rough Opening Width Formula
— Nominal Door Width + 2.0 inches (51 mm)
Rough Opening Height Formula
— Nominal Door Height + 2.5 inches (64 mm)
30×80" Bedroom Door (2/6 × 6/8)
— Rough Opening: 32.0 × 82.5 inches (813 × 2096 mm)
32×80" Standard Entry (2/8 × 6/8)
— Rough Opening: 34.0 × 82.5 inches (864 × 2096 mm)
36×80" ADA Entry (3/0 × 6/8)
— Rough Opening: 38.0 × 82.5 inches (965 × 2096 mm)
Standard 2×4 Wall Jamb Depth
— 4-9/16 inches (116 mm) = 3.5" stud + two 1/2" drywall layers
Standard 2×6 Wall Jamb Depth
— 6-9/16 inches (167 mm) = 5.5" stud + two 1/2" drywall layers