5-inch or 6-inch gutters: which does your house actually need?

Gutters are the least interesting part of a house right up until they fail, at which point they become a foundation problem, a landscaping problem and sometimes a crawlspace problem. Getting the size right is most of the job.

What the size actually changes

A 5-inch K-style gutter is the standard residential size and it handles most homes without trouble. A 6-inch carries noticeably more water, and — this is the part people miss — it pairs with a larger downspout, which is usually where a gutter system actually chokes.

More capacity is not automatically the right answer. On a modest roof, 6-inch is a bigger, heavier, more visible gutter solving a problem you do not have.

When 6-inch is the right call

• Steep roofs. A steeper pitch throws water at the gutter faster and harder, and a 5-inch will overshoot in heavy rain
• Long runs. A forty or fifty foot elevation collects a lot of water before it reaches a downspout
• Large roof areas draining to few outlets
• Heavy tree cover. Around here that usually means pines, and pine straw is the single most reliable way to block a gutter. A larger trough and a larger downspout clog less and are far more forgiving
• Valleys that dump into one section of gutter, which concentrates a lot of water in a short length

When 5-inch is genuinely fine

A typical single-storey or two-storey home with average pitch, reasonable run lengths and no heavy tree cover is well served by 5-inch. It sits neater against the fascia and costs less, and upsizing it would be selling you metal you do not need.

If a contractor quotes 6-inch on every house without looking at the roof, they are not sizing anything. They are just quoting.

Why seamless matters more than size

Sectional gutter comes in short lengths and gets joined together on the wall. Every joint is a place that can eventually work loose and drip, and they generally do.

Seamless gutter is formed as one continuous piece for the whole run. A forty-foot side of your house has no seam in the middle of it at all — only at the corners and outlets, where you cannot avoid them.

We own our gutter machine and bring it with us, so the coil is rolled and cut to the exact length of each run in your driveway. Most contractors either sub gutters out or hang sectional gutter from a big-box store. Doing it ourselves is why we control the fit and the schedule.

The thing behind the gutter

A gutter is only as sound as the board it hangs on. If your fascia is soft or rotten, new gutter will pull away from it eventually no matter how well it is hung.

When we find rot we replace the board with new wood and run PVC trim over the top. We do not wrap aluminium over rotten wood to make it look tidy — that hides the problem and the first sign you get is the gutter coming off the house.

Gutter guards, honestly

Guards genuinely reduce how often you are up a ladder, particularly under pines. They are not a promise that you will never clean a gutter again, and anyone telling you otherwise is overselling.

They are usually worth it under heavy tree cover and often not worth it on an open lot.