Gutters & Drainage
Size and cost a gutter system: gutter length and downspout count from your eaves, 5-inch vs 6-inch K-style sizing from drainage area × roof-pitch factor × your local rainfall intensity, downspout capacity, slope, and cost on your own rates. Working at height is dangerous — use fall protection.
Working on a roof is dangerous — falls are a leading cause of construction deaths. Measure from the ground, from plans or from photos where possible, use proper fall protection if you must go up, and consider hiring a licensed roofing professional. Results are planning estimates, not a bid.
Gutter LengthAdd up your eave runs to get the total gutter footage and the number of downspouts you need, at one outlet per 30 to 40 linear feet of gutter.Gutter SizeDecide between 5-inch and 6-inch K-style gutters from the roof drainage area, the roof pitch factor and your local rainfall intensity in inches per hour.Downspout CapacityFind how many 2x3-inch or 3x4-inch downspouts a roof needs from its adjusted drainage area, using industry outlet capacities at one inch per hour.Gutter SlopeWork out how much to drop a gutter run toward the downspout at a quarter inch per ten feet, including long runs pitched from a high center both ways.
Every Gutters & Drainage tool is calculated server-side — visible immediately — with its formula, a worked example and a reference table. Background reading is in the guides.