The cap, exactly
Cover runs to 5,000 sq ft of treated surface. Above that the cover does not stop, it reduces proportionally: a larger roof keeps the same rate and a share of the total instead of hitting a cut-off.
That is a different thing from the maximum value per square foot, which is quoted on every row and sets the rate the cover works at. The cap sets the size of surface that rate applies to at full weight.
Why the area still needs measuring
The area of the roof is what turns a per-square-foot figure into an amount, so it has to be measured rather than estimated from the street. That measurement is part of the assessment, alongside the condition score.
It also decides the scope of the work: how much surface is cleaned, how much treatment is needed, and how the two-coat builds are planned for the day.
How the ratio reaches a claim
The area-cap ratio is one of the four numbers in the allowance calculation: affected square feet, times the maximum value per square foot, times the claim-year percentage, times the ratio.
On a roof under 5,000 sq ft the ratio is 1, so the first three numbers decide it. On a larger roof the ratio makes the proportional reduction the terms describe.
- 5,000 sq ft or less: full cover
- 6,000 sq ft: five sixths of the allowance
- 10,000 sq ft: half of the allowance
What to ask about a large roof
On a large or complex roof, the useful questions at the assessment are how the area was measured, which row the score supports, and what the scope covers on that specific roof shape.
All three are answered in the estimate, which costs nothing to receive.
What a large roof changes
The rate stays the same and the ratio does the rest. A large roof is covered at the same value per square foot as a small one, with the area-cap ratio reducing the total in proportion once the surface passes the cap.
That is one reason the assessment measures the roof rather than estimating it from the street: the measured area is what turns a rate into an amount, on both sides of the cap.