On-Site Clearance & Measurement Guide

Before ordering a metal building, you must verify that the chosen location has adequate physical clearance. Standard building dimensions represent the footprint of the frame itself—not the maximum space the roof or building profile will occupy.

Here is how to perform an accurate site survey. Pair this checklist with the dimensions guide if you haven’t settled on a width, length, and leg height yet.

1. Frame Footprint vs. Roof Overhangs

A common error is neglecting the “drip edge” or roof eave overhang:

• Boxed Eave & Vertical Overhangs: Boxed-eave (A-frame) and vertical roofs feature a 6-inch overhang on each side. A 20-foot wide building will actually have a total roof width of 21 feet.
• Regular Roof Overhangs: Regular style (curved-corner) roofs typically have no side overhangs, as the sheet metal bends directly over the frame legs.
• Front & Rear Overhangs: All roof styles feature a 6-inch overhang on the front and rear gables.

2. Obstacles & Clearances

When mapping out the location of your steel garage or carport, check for these obstacles:

• Tree Branches: Ensure there are no overhanging limbs within 6 feet of the building height. Branches rubbing against metal panels can scrape off the protective paint finish, leading to rust.
• Power Lines: Federal regulations require a minimum clearance (usually 10 feet) between any structure and active overhead power lines. Contact your utility provider to check local standards.
• Fences: Leave at least 3 feet of walking space between your metal garage and property fences. The installation crew requires this space to stand ladders and secure the side wall sheet metal.

3. Measuring Height and Clearance Conflicts

Steel buildings are sized by their side leg height, not their peak height:

• Side Height: The height from the ground to the top of the side wall (where the roof starts).
• Peak Height: The height at the highest center point of the roof. This is determined by the pitch (usually 3:12 or 4:12) and the width of the building.
• Door Clearance: Ensure your roll-up doors have enough headroom. A 10-foot tall leg height can accommodate up to an 8-foot tall roll-up door.

Clearance Checklist

Obstacle	Minimum Clearance	Why It Matters
Overhanging tree limbs	6 feet above building height	Prevents paint scraping and rust points
Overhead power lines	10 feet (verify with utility)	Federal/utility safety requirement
Property fences	3 feet of walking space	Installers need room to stand ladders and panel the walls
Roof drip edge (boxed eave/vertical)	+6” per side beyond frame width	Roof overhang extends past the footprint

[!TIP] Measure twice against your actual property survey, not just a tape-measure guess. Also confirm your city or county’s permit requirements for setbacks before you lock in a location, since setback rules are usually stricter than the physical clearances above.