How does the estimator work?
A roofing square is 100 square feet. To estimate yours, take the area each floor covers (living area divided by stories), add a garage if it shares the roof, and scale up for slope, because pitched surfaces are longer than the floor below them. Eaves and overhangs add roughly another 5% to 20%. The roofer's measurement replaces all of this.
What do typical Marin homes come to?
These examples use the same geometry. They describe roof area only, not price.
| Example home | Footprint under the roof | Pitch | Roofing squares (approx.) |
|---|---|---|---|
| Terra Linda or Novato ranch, 1,700 sq ft, one story | about 2,100 sq ft | 4-in-12 pitch | 23 to 27 |
| Mill Valley hillside home, 2,200 sq ft on two levels | about 1,100 sq ft | 8-in-12 pitch | 14 to 16 |
| Ross Valley shingle-style house, 3,000 sq ft | about 1,500 sq ft | 10-in-12 pitch | 21 to 23 |
What makes a roof in Marin cost more than its size suggests?
Marin roofs split into two broad types. Post-war ranch tracts in Terra Linda, Novato and parts of San Rafael have simple, low-pitch roofs that price close to their size. Older and hillside homes in Mill Valley, Sausalito, Tiburon and the Ross Valley are steeper, shaded by redwoods and oaks, and often reached by stairs, so labor per square climbs. Moss holds water against the roof deck, and rot found at tear-off is priced on top. Shake roofs still turn up, and replacing one usually means new solid decking.
What price range should I expect?
National cost surveys such as the Cost vs. Value report put a full asphalt-shingle reroof in the tens of thousands of dollars, with metal well above that. We don't publish a per-square or per-city price, because layers, decking, access and material swing real bids too much for one number to be honest. For your actual price, request a free written estimate: a licensed roofer measures the roof and prices your exact scope.
What should I have ready for an estimate?
- Rough square footage and stories
- The year of the last reroof, if you know it
- Solar, skylights, chimneys or flat sections
- Any insurer letter about the roof
Related: what drives roof replacement cost, metal roofs, dry rot and decking, solar removal and reinstall and our quote checker.
Every roofer we work with is licensed, insured and highly reviewed by Bay Area homeowners.
Get a free replacement quoteFrequently asked questions
What is a roofing square?
100 square feet of roof surface. Roofers measure and price in squares; the number depends on footprint and pitch, not just living area.
Can I get a price per square foot from you?
We don't publish one. Real bids vary with layers, decking, material and access, so ask for a free written estimate that shows the scope.
Why did my Mill Valley quote come in higher than a friend's in Novato?
Steeper pitch, stairs or hillside staging, tree damage and more complex roof shapes add labor even when the homes are a similar size.
Sources
Sources reviewed November 12, 2026. Figures are published estimates and official fees, not quotes. Confirm prices, permits and requirements with your contractor and building department. This page is general information, not legal or insurance advice.