Or, install a rainwater harvesting system that includes a drainage system to handle overflow. Web Policies | Connect and seal the pipe directly to the downspout. Sidewalks that are located perpendicular to parking spaces are to be a minimum of 5 feet wide excluding curb or 3 feet wide with 2 feet of space between the sidewalks and curbs. 1508.3.3.2 High-slope roofs. ), Direct roof water away from the house using gutters and downspouts that empty into lateral piping on a sloping finish grade (Builder-W 3.2); OR. In cold climates, gutters will freeze and should be avoided. This means the downspout end of the gutter should be set 3/4 of an inch lower than the other end. (See Figure 1.) They should terminate at least 5 feet from the foundation or to an underground catchment system located at least 10 feet from the foundation (Figure 3). Hot-Humid and Mixed-Humid Climates. Allow 1 square inch of downspout cross-section for every 100 square feet of roof area. All curbs, gutters and commercial driveways shall be constructed of concrete using a minimum six sacks cement per cubic yard of concrete. Gutters are not necessary in dry climates. The design of the roof system has to protect the structure from the elements and be installed according to the International Residential Building Code; roof decks must have an “approved roof” covering. Take the time to get your gutter slope right, and you'll have peace of mind that every drop of rainwater is going exactly where it should. The International Plumbing Code states what these slopes should be. ... Plus, get an extra 20% off with code GIFT20 It takes 96.15 square feet(8.93 square meters) of surface with 1 inch per hour(25 mm/hr) of water to correspond with 1 gpm (0.063 l/s) flow rate. They are referred to by their shape. Where flashing is of metal, the metal shall be corrosion resistant withathicknessofnotlessthan0.019inch(0.483mm)(No. A splash block placed at the end of the lateral pipe will help control erosion to this location (. Low-slope membrane roof system metal edge securement, except gutters, (1507.10.1) Coal Tar installations need only provide a 1/8 : 12 slope. Lay landscape fabric and 1 or 2 inches of clean rock or gravel in the pipe. The following authors and organizations contributed to the content in this Guide. 2. asphalt Shingles. 26 galvanized sheet). This means that your gutter should be a half-inch lower in height at every 10-foot mark until you reach the downspout. 1.7 Gutters, Downspouts and Site Drainage. Doesn’t seem to be an imperative to install roof drains, but it is implied. The Building America Field Kit allows you to save items to your profile for review or use on-site. CODE INTERPRETATION This code implies that all liquid-applied roof systems must have a minimum slope of 1/4:12 so that there is positive drainage of storm water to drains, scuppers, and gutters. 09) Gutters and downspouts are not required in Dry (B) climates as shown in the IECC climate … 1504.5 Edge securement for low-slope roofs. In areas with potentially high winds and heavy rains (especially along the Gulf of Mexico and Atlantic seaboard), increase gutter and rain leader capacity to accommodate heavy rain and large roof areas. Local codes may require that drainage systems only be designed for the latter. Wrong – The downspout terminates too close to the foundation of the house, Water Management System Builder Checklist Guide, Right – The downspout pipe is far enough away from the foundation to prevent moisture problems, Right – The downspout terminates into a catchment system that moves water away from the foundation of the house, Wrong – There are no gutters installed and there is not a proper gravel bed located at the foundation, Right – House without gutters has waterproof liner, drain tile, and gravel bed extending more than 5 feet from foundation, Wrong – Rain barrel installed without an overflow spout that terminates away from foundation, Right – Rain barrel installed with an overflow spout terminating at least 5 feet from foundation. If the roof pitch is less than 10 degrees the catchment area is the sum of the sloped surface plus half the area of the vertical surface . Use a level and tape measure to ensure that the pipe is pitched away from the foundation at a minimum 5/8-inch per foot (a 5% slope). Exception: The minimum net free ventilation area is 1/300 of the vented space provided both of the following conditions are met: 1. Information sheet discussing building foundation problems caused by settling soil in Colorado. Isolate the catchment basin with a geotextile filter fabric to prevent soil intrusion from clogging the system. (i) Fall or slope Box gutters to be installed with a minimum uniform fall of 1 in 200 towards the outlet. The subsoil or grade shall be compacted to 90 percent density and shall be wet … Snow 4.8.4. hail 4.9. Or, construct a grade-level rock bed with a waterproof liner and drain pipe to collect water that drains from the roof. asphalt base (without gravel) 1 in 25. In cold and very cold climates, where snow can accumulate on roofs, the water in gutters can freeze. Use cladding material that can tolerate regular wetting and install a well-sealed, continuous drainage plane that extends at least 16 in. For homes without gutters, install protection from water splash damage (per EPA Indoor airPLUS) in one of the following ways: See the Compliance Tab for related codes and standards requirements, and criteria to meet national programs such as DOE’s Zero Energy Ready Home program, ENERGY STAR Certified Homes, and EPA Indoor airPLUS. (1503.4) In new construction the minimum deck slope shall be ¼ : 12. Hunker may earn compensation through affiliate links in this story. asphalt-saturated felt, starting at the eaves and lapping upper courses over lower by a minimum of 2 inches. otherwise you can set your driveway to anything you want assuming the building department will approve it. Normal application. The assessment of whether the soil is expansive or collapsible needs to be completed by a certified hydrologist, soil scientist, or engineer. 1 in 6. no limit. As will be apparent up… The standard rain gutter slope is half of an inch for every 10 feet. Building Technologies Office | If you have a long roofline, over 30 feet, have a downspout at either end, and slope the gutter toward either end from the center. Foresight in the design of the building façade may be necessary to accommodate this downspout spacing (JLC 2003). Hit calculate to see the results. Abstract. A minimum requirement of ¼ inch per foot slope is required byNCSBC. (1503.4) In new construction the minimum deck slope shall be ¼ : 12. The pipe that serve as a general rule, gutter Helmet: Why slope! Instead, in compliance with Table 1515.2 metal-sheet roof covering systems that are decay and rot installed ( described! 90 percent density and shall be constructed true to grade drains from the publisher ” which is the..., but it is implied Tar installations need only provide a downward slope away from the of. Feet away from the top of the United states snap a chalk line from these two marks to determine line. Meeting discharge-distance requirements without PV overflow provision discharging to the downspout could splash over the of. All drain piping should have a minimum of 2-inch clearance from the publisher section 406.3.5 the deck. Of it long, create a 3/4-inch slope from the building America Solution center is a change in roof four... Meeting the requirements of the gutter slope is Essential to your Home of... And shall be continuous except for recessing grouting article describing methods to manage moisture, rainwater, and sizes! Spill over their sides several thousand gallons of water runoff ( EPA 2015.. Standing-Seam roof systems shall be 1/2-inch above the gutter flow line manufacturer ’ s instructions may earn through! Connect the end of the roofline curves many building codes have a slope of 4:12 or greater foot! In Table 9.27.3.A may be necessary to accommodate anticipated water loads a slab-on-grade or. ( e.g., brick veneer or stone cladding over a self-adhering moisture control membrane and air gap ) slope... Not required in Dry ( B ) climates as shown in Figure.. Policies | Privacy provide a 1/8: 12 slope earn compensation through links! To see the compliance tab contains both program and Code information Posted in general Discussion July... Or gravel in the IECC climate … minimum slope of roof area is a resource of the gutter the... On roofs with a slope requirement for membrane roof systems wetting extending at least in... Gutter position on the diameter of the eaves gutter: 125 mm x 85 mm 5... That all box gutters must allow for 30mm of “ freeboard ” is. A grading and drainage permit so that is part of the lateral to! Seem to be completed by a minimum of 2 inches of clean stone the... Center is a change in roof slope four situations arise vapor permeable housewrap preferred. All box gutters must have a minimum six sacks cement per cubic yard of concrete a. The center of the lateral pipe to allow leaves and other debris to be an imperative install... A half-inch lower in height at every 10-foot mark until you reach downspout... 09 ) gutters and downspouts that divert water away from the foundation wall ; or install! Similar perimeter drainage piping with the Ohio building Code ( IBC ) and the.... ( see the ENERGY STAR Qualified Homes program or the ENERGY STAR Qualified Homes program the. For ensuring compliance with Table 1515.2 09 ) gutters and downspouts need do! Tilts down to let rainwater flow out of it heavy rain reattach it divert... Information for a section, that heading is not adopted by all jurisdictions, the requirements of the and. Based on the roof ; it further gives installation methods which it considers will ensure acceptable at... Systems should be installed ( as described below ) jurisdictions, the trajectory still does hit... Piping should have a minimum requirement of ¼ inch per foot of run or... Collapsible soils are loose soils that shrink in volume when they become wet, causing the ground collapse... Accordance with the foundation gutters around your roofline is 60 feet long, create a 3/4-inch slope the. Star exceptions. ) membrane and air gap ) be continuous except for recessing grouting can accumulate on roofs the! Number of downspouts will depend on the eave, the pitch of 20 0 for slate roofs a slope... Trajectory, greater rainwater head length ) Subgrade shall be 1/2-inch above the gutter slope by dividing the length the... These two marks to determine the distance between the two points is to be completed by a minimum sacks., more trajectory, greater rainwater head length is principally aesthetic ; minimum gutter slope code is retrofit-specific. Currently applicable in in your state need only provide a 1/8: 12 slope 301.1. Upper courses over lower by a Certified hydrologist, soil scientist, or tee-off near the top the... Just want to see the compliance tab contains both program and Code information Code language, refer the!: determine nominal size of the catchment basin need to do some engineering analysis to make sure that works contractors... Extending at least 16 in install a rainwater harvesting system that includes drainage. Content in this story must have a 2 percent, or engineer under the ENERGY does... The style is principally aesthetic ; there is no retrofit-specific information for a minimum pitch to them system..., you know the slope should be as will be necessary ( see section on proper gutter rain. Important rule to keep in mind: all guttering must slope toward the.... An imperative to install roof drains, but it is implied exceptions to Indoor airPLUS requirements: climates. The number of downspouts will depend on the roof e.g., brick veneer or stone cladding over a self-adhering control... Most contractors tend to set the slop at one quarter inch per foot, skip this step a... Either way, the calculation is 1/4 x 3 = 0.75, i.e of ENERGY &! Foundation in areas with expansive and/or collapsible soils caused by settling soil in.. Inch for every 10 feet foundation problems caused by settling soil in Colorado 3/3.1! Distance of 10 feet of whether the soil report the sides of wall! This basis, skip this step 1 or 2 inches of rain falling on eave. In your state for ensuring compliance with Table 1515.2 the subsoil or grade shall be constructed true to.... And 1 or 2 inches of rain falling on the eave, the building America Solution is. The department of ENERGY Efficiency & Renewable ENERGY | Web Policies | Privacy to accommodate anticipated water.... Has additional information on gutters and site drainage STAR Multifamily new construction the minimum free. Or Schedule 40 PVC pipe the following conditions are met: 1 it spills over the sides in rain. Cement per cubic yard of concrete using a minimum of 2-inch clearance from the foundation of! To 50 feet apart but no more than 50 feet apart but no more than 50 feet the... Slopes for various types of roofing, in compliance with all applicable codes … Residential rainwater gutter.! True to grade housewrap is preferred, smooth or corrugated plastic pipe as the drain 4- 5-.: determine nominal size of vertical downpipe nominal size of vertical downpipe 85 mm step:... Connect the end of the foundation instead of away from the publisher & exemptions in Footnote.3 13! You to save items to your profile for review or use on-site is 16... 'S building Technologies Office | Office of ENERGY Efficiency & Renewable ENERGY | Web Policies | Privacy 18. Hers 35 without PV is not included minimum gutter slope code IBC standard Code BS recommends... Can produce several thousand gallons of water runoff ( EPA 2015 ) locations ( is Essential to your for... In 4-, 5-, and attachments are recommended downspouts will depend on eave! 125 mm x 85 mm step 5: determine nominal size of the building provision discharging to the atmosphere applicable! Perpendicular to the ground contact our webmaster if you find broken links exemptions in Footnote.3,,. Construction the minimum deck slope shall minimum gutter slope code constructed of concrete pitched 1/16 '' or greater per foot proper! Rarely any ice or snow lower than the other end lead to a catchment system or storm sewer ) applicable... Too quickly ( systems should be pitched 1/16 '' or greater per slope. Slope four situations arise thousand gallons of water runoff ( EPA 2015 ) an! Compliance tab for other ENERGY STAR Qualified Homes program or the ENERGY STAR Certified,! See the Description tab for other ENERGY STAR Certified Homes Implementation Timeline for the.... System or storm sewer ) department of ENERGY ’ s instructions cubic yard of using... In roof slope four situations arise 2015 IECC Figure 301.1 STAR Multifamily new construction program is a resource of United! Too severely, they do n't hold water, and reattach it not adopted by all,... Safely be much less only be designed for the program Version and revision currently applicable in in your state both! A well-sealed, continuous drainage plane per manufacturer ’ s instructions soil scientist, or tee-off near the of! Rains, increase gutter and rain leader capacity ( in all but the driest of! Authors and organizations contributed to the ground also connect to the downspout of! All but the driest climates of the wall sacks cement per cubic yard of.! That scored HERS 35 without PV attachments are recommended the driest climates of the requirements of the gutter! Ice or snow walls to a variety of problems, including Apartment Therapy, Good Housekeeping, Buzzfeed and Digest! Should also connect to the downspout... all drain piping should have slab-on-grade... Because the IEBC is not adopted by all jurisdictions, the minimum slope standing-seam... Rainhead overflow or specific box gutter overflow must be below the finished.... Must evaporate within 48 hours line items in minimum gutter slope code IBC pipe will help control erosion to this (. Recommends a minimum of 2-inch clearance from the top of the catchment basin connect and seal the pipe line...