Methodology

We read the published cost guides and print what each one says, side by side, with the publisher named and the day we read it. We do not average them. On aluminum the published figures run from $7 a foot to $20, and on copper from $15 to $73.80. An average would hide that spread behind a tidy number, and the spread is the most useful thing on the page.

Where we do arithmetic on somebody else's figures, we say so on the spot and show the method. Dividing a publisher's whole-house total by the footage it assumed is our division, not their number, and it is labeled that way every time.

We name it when a publisher contradicts itself, because that tells you how much weight a figure carries. One guide prices box gutters with the same three numbers it uses for gutters of every type. Another gives the same product two prices, two and a half times apart, on two of its own live pages. A third carries 2022 pricing under a 2026 title.

Every number we use is tagged one of four ways. Measured means we got it from a named source. Derived means we did the math on measured numbers, using a rule we state. Estimated means it is our best guess, and we say so on the page. Open means we have not pinned it down yet. An open number never goes on the site.

If we cannot read a figure at its own source, we do not print it, even when everybody else does. Two examples are on this site. A 35 foot downspout interval is quoted all over the trade; it traces to a document behind a bot block, so we use the interval we could read instead. And no cost guide we could reach publishes a price for relining a built-in gutter, so that page publishes none rather than repeating a number we cannot check.

We trust these sources, roughly in this order:

• U.S. government agencies. NOAA for rainfall data, and the National Institute for Occupational Safety and Health for the ladder-fall figures
• Building codes and agreed technical standards. The International Plumbing Code and the residential code as published, and ASTM material standards
• A maker's own catalog or specification sheet, when the question is about that product. Amerimax, Berger, Englert, Spectra, and the manufacturer drawings for profile dimensions
• Industry groups, such as the Copper Development Association. We label these, because they are not neutral
• Published cost guides, for prices only, never for physics. Where one makes a claim about how much water a gutter holds, we check the arithmetic before repeating it, and we have thrown one out for being impossible

Some advice is a judgment call, not a rule. When it is, we say it is our view. And when the rules differ from state to state, we say that too. We do not smooth it over.

• We do not make up writers, job titles, licenses or awards.
• We do not print reviews, star ratings or quotes from happy customers. We have no real ones.
• We do not pass off stock photos as our own work or our own crew.
• We do not claim years in the trade that the company behind this site has not put in.

Every page shows a "last reviewed" date. It is a real date, from a day someone checked the page. It is not a clock that ticks itself forward.

Found a mistake? Tell us: compassleadgroup@gmail.com. The page gets corrected. And if the correction would change what you decide to do, we write down what changed. We do not edit it quietly and hope nobody noticed.

Gutter prices change from place to place. Our ranges cover the whole country. So a range is wider than the price in your town. We would rather give you a wide range and say why than give you one sharp number that is wrong almost everywhere.