Pitch or steepness also is a factor.
Irc gutter slope.
An inch of rain is not much but it if falls in half an hour it could flood a gutter.
For roof slopes of three units vertical in 12 units horizontal 25 percent slope and greater valley flashing shall have a 36 inch wide 914 mm.
102 mm in width and shall direct water away from the vertical sidewall onto the roof and or into the gutter.
The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.
Slope shape figure 59 gives an indication of surface and subsurface water concentration or dispersion.
Straight slopes concentrate water on the lower slopes and contribute to the buildup of hydrostatic pressure.
The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.
Wherever there is a change in roof slope or direction and around roof openings.
6 2014 section ii loads and stresses revised edition irc.
Section 1505 15 1 slope liquid applied roofing shall have a design slope of a minimum of 1 4 unit vertical in 12 units horizontal 2 percent slope.
09 gutters and downspouts are not required in dry b climates as shown in the iecc climate zone map 2009 iecc figure 301 1 and table 301 1.
Water will run off faster from a very steep roof than from one with a gradual slope.
The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.
Slope the grade away from the building as recommended in the guide final grade slopes away from foundation energy star certified homes version 3 3 1 rev.
5 1998 section i general features of design seventh revision irc.
International residential code 2012 irc 2012.
Slope the final grade away from the house at least 0 5 inch per foot for 10 feet.
2009 2012 2015 and 2018 international residential code irc.
The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.
Convex slopes e g wide ridges will tend to disperse water as it moves downhill.
Total roof area also affects runoff.
22 2008 section iv composite construction for road bridges second revision.
Where siding is provided on the vertical sidewall.
102 mm in width and shall direct water away from the vertical sidewall onto the roof or into the gutter.
Concave slopes typically exhibit.
Information about gutters and downspouts is covered in depth in the guide gutters and downspouts.
A roof of 1 200 square feet in size will collect more water than one that is 600 square feet.