A 1/12 roof pitch — referred to as “1 over 12” — is one of the flattest roof slopes still considered a pitch. “1 over 12” means the roof rises just 1 inch for every 12 inches of horizontal run. This equals an angle of about 4.76 degrees, creating a nearly flat appearance while still allowing minimal water runoff.
What Does a 1-12 Roof Pitch Represent?
With a 1/12 pitch, the roof rises 1 inch for every foot of horizontal span. This translates to an angle of approximately 4.76 degrees and a slope of 8.33%. It’s a very low-slope roof, often used where appearance matters less and drainage needs are minimal.
- Pitch: 1/12 (or “1 over 12”)
- Angle in Degrees: 4.76°
- Slope Percentage: 8.33%
- Rafter Length (per 12 inches of run): Approximately 12.04 inches
Not sure about your roof pitch? Try our calculator for an instant answer.
Is a 1-12 Roof Pitch a Good Choice?
It depends — a 1/12 pitch is best suited for areas with minimal rainfall or for specific roof designs like commercial buildings. While it doesn’t shed water quickly, it can still work with proper waterproofing. Here’s why you might choose this pitch:
- Suitable for dry climates or minimal precipitation
- Works well with roofing membranes and metal panels
- Low-profile design for modern or commercial buildings
- Accessible for maintenance and inspections
Installation & Cost Insights
A 1/12 pitch roof is simpler to walk on and easier to install compared to steeper slopes. Labor costs are generally lower, but you’ll need to invest in proper waterproofing materials to avoid leaks.
How Does it Compare in Degrees to Other Roof Slopes?
At around 4.76 degrees, a 1/12 pitch is among the lowest sloped roofs that still qualifies as a pitched roof. It’s much flatter than common residential slopes like 4/12 or 6/12, and requires specific materials for weather protection.
What is the Angle in Degrees for a 1-12 Roof Pitch?
The angle for a 1/12 roof pitch is approximately 4.76 degrees. Explore our full pitch chart to compare all roof slopes and angles.
Understanding your roof pitch angle helps ensure proper material selection and waterproofing, especially for low-slope roofs like 1/12.
Where Do You See 1/12 Roof Pitches?
The 1 over 12 pitch is common in commercial and low-profile buildings where a flat appearance is desired. You’ll often see this pitch in:
- Commercial flat roofs — Designed with membranes or metal panels for waterproofing
- Modern homes — Minimalist look with slight slope for drainage
- Detached garages and sheds — For budget-friendly construction
- Covered patios — Subtle pitch to guide water away from the structure
- Dry climate regions — Minimal slope works in low rainfall areas
Builders choose the 1/12 pitch for its affordability and ease of installation, especially in projects where a low profile is preferred.
Overall, the 1/12 roof pitch is an economical choice for specific applications, providing a simple and accessible design when paired with the right materials.