Gambrel Roof Cost Calculator

Calculate gambrel (barn-style) roof cost based on building dimensions, roof angles, and material type — with full area and cost breakdown.

Project Details

Width of the building (gable end to gable end)

Length of the building (ridge direction)

Angle of the steep lower section — typically 60-70 degrees

Angle of the shallow upper section — typically 25-35 degrees

Estimated Cost

Low

$13,290

Average

$24,665

High

$39,064

Cost Breakdown

Materials

ItemQtyLowMidHigh
Asphalt Shingles1741 sq ft$2,612$5,223$8,705
Underlayment & Ice Shield1741 sq ft$522$871$1,393
Framing & Trusses (Gambrel)1741 sq ft$3,482$6,094$8,705
Ridge Cap, Drip Edge & Flashing140 linear ft$280$560$980
Subtotal$6,896$12,748$19,783

Labor & Fees

ItemQtyLowMidHigh
Roofing Installation Labor1741 sq ft$5,223$9,576$15,669
Tear-Off (if re-roofing)1741 sq ft$871$1,741$2,612
Permit & Dumpster1 flat$300$600$1,000
Subtotal$6,394$11,917$19,281

Notes

  • Total roof area: 1,741 sq ft (17.4 squares). Peak height: ~15 ft.
  • Gambrel roofs cost 15–25% more than standard gable roofs due to increased complexity.
  • Asphalt shingles are the most affordable option but may not perform as well on the steep lower slope.
  • Framing costs included — gambrel trusses are more complex than standard gable or hip trusses.

About the Gambrel Roof Calculator

A gambrel roof features the distinctive barn-style double slope on each side — a steep lower section and a shallower upper section meeting at a break line. This design maximizes usable upper-floor space, making it popular for barns, workshops, and homes where attic livability is desired. Our calculator estimates the total cost of a gambrel roof including materials, framing, and labor based on your building dimensions and roof angles.

How We Calculate Gambrel Roof

We calculate the total roof area using gambrel geometry: the building width is divided into lower and upper sections on each side, with slope lengths determined by the specified angles. The four panels (two per side) are multiplied by building length to get total roof area. Material costs, underlayment, framing, and trim are calculated per square foot. Labor accounts for the added complexity of gambrel framing and the break-line flashing.

Factors That Affect Gambrel Roof

Key factors affecting gambrel roof cost include: building dimensions (width and length), roof angles (steeper lower slopes increase area), roofing material choice, whether this is new construction or a re-roof (tear-off adds cost), local lumber and labor rates, and any dormers or windows planned for the upper floor.

Planning a larger project? You may also want to estimate costs for soffit installation cost, garage door spring replacement cost, or foundation repair cost.

Sources

  • HomeAdvisor — 2025 Roof Installation Cost Guide
  • Fixr.com — Cost to Build a Gambrel Roof
  • RSMeans Building Construction Cost Data 2025

Pricing data as of 2026. Costs vary by location and market conditions.

Frequently Asked Questions