The short answer
To hang gutters, check that the fascia board is solid, plan your downspout locations, then snap a chalk line along the fascia that slopes about 1/4 inch for every 10 feet of run toward each downspout. Mount hangers every 2 feet along that line (closer spacing helps under Michigan snow), seal every seam and end cap, and run downspouts with extensions that carry water several feet away from the foundation.
Check the fascia first
Gutters are only as strong as the board they are screwed to. Press on the fascia along the roof edge. If the wood is soft, cracked or peeling, replace it before you hang anything. New gutters on rotted fascia will pull away within a season, especially once snow and ice load them up.
Plan the downspouts
Decide where water should go before you cut anything. A common rule of thumb is one downspout for roughly every 30 to 40 feet of gutter. On long runs, pitch the gutter from the middle down to a downspout at each end instead of running it all one direction.
Snap a sloped line
Mark the high end of the run just under the drip edge, then measure down about 1/4 inch for every 10 feet of length and mark the low end at the downspout. Snap a chalk line between the two marks. Too little slope leaves standing water; too much looks crooked from the street.
Mount the hangers
Fasten hidden hangers into the fascia along the chalk line about every 2 feet, and every 16 to 24 inches on runs that catch a lot of snow or roof valley water. Drive the screws into solid wood, not just through it.
Seal seams, ends and outlets
Seal end caps, inside and outside corners and the downspout outlet with gutter sealant. One continuous seamless gutter avoids most seam leaks, but needs a forming machine, which is why many people hire that part out.
Run the downspouts away from the house
Attach downspouts with brackets and add extensions or splash blocks that send water several feet from the foundation, ideally 4 to 6 feet. Water dumped right at the wall is one of the most common causes of wet basements.
When to call a pro
Hire it out if the house is two stories, the fascia is rotted, you want seamless gutters or you are not comfortable working from a ladder. Quality Finish repairs the fascia and roof edges gutters depend on, so call us if your gutters are pulling away from the house.
Exterior and roofline repair in Southwest MichiganCommon questions
How much slope should a gutter have?+
About 1/4 inch of drop for every 10 feet of gutter, toward the downspout.
How far apart should gutter hangers be?+
About every 2 feet, and closer, around 16 to 24 inches, where heavy snow or roof valleys load the gutter.
Why are my gutters pulling away from the house?+
Usually because the fascia board behind them is rotted or the hangers are not fastened into solid wood.