The gutter outlet capacity should suit the downspout wikiHow is where trusted research and expert knowledge come together. Determine the size of your downspout. 6. This procedure for sizing gutter systems is based on roof size, the area's likely rainfall intensity, gutter volume and downspout size and frequency. Expert Interview. Press a downspout adapter into a 3x4-inch reducer coupling and slip it onto the bottom end of the downspout. Assessing Rainfall Intensity. Detail drawings and dimensions will follow the table for each of the gutter designs. The size of the downspout should be constant through-out its length. This rule of thumb works for most situations, but ultimately the sizing depends on the strength of local storms, the pitch of the roof, and the slope of the gutter. All Rights Reserved. Results will be tabulated so that you can easily see results as you change variables. Downspouts should be constructed with conductor heads every 40 ft(12.2 m) to admit air and prevent vacuum. Then, mark the end point with chalk, note down the measurement, and move your ladder to the chalk mark. Measure, mark, and dig a trench near from the downspout towards the main storm drains. Cut a piece of pipe to match with a handsaw, hacksaw or 12-in. As a general rule, eGutter™ recommends for roof areas that exceed 2800 square feet, a 6" K Style size with a 3"x 4" downspout size would be appropriate. Note that this application is intended as a aid only, and is provided as is. The downspout size must suit the bottom width of the gutter. The size of the downspout should be constant through-out its length. Please lower the maximum spacing between downspouts to see this effect. Get in contact with us on 0800 644 44 26 or email sales@rainclear.co.uk. Measuring Tape; Chalk; Paper; Pen; Gutters. References. (and the size of offset you need to order) The minimum ratio of depth to width should be 3 to 4 inches. Gutter and Downspout Combinations. Round pipe systems are more flexible to install, as offsets can be “swung” or twisted into alignment with the gully position. Lay the new downspout pipes by the trench for easy access during installation. Press a downspout adapter into a 3x4-inch reducer coupling and slip it onto the bottom end of the downspout. This application runs the equations laid out in the Smacna handbook. For instance, a 2 in (5.1 cm) gap means the roof has a 2-in-12 pitch and a 6 in (15 cm) gap means the roof has a 6-in-12 pitch. Most roofs are symmetrical so you can enter the number of downspouts attached to the surface area that you just measured. With over ten years of experience, Barry specializes in a variety of carpentry projects. spout drains 1,200 sq. It should be used to calculate required gutter size, downspout size, and downspout spacing for a given roof area. Refer to the gutter packaging or specification for the recommended downspout size. Step 1 - Measure the Length of the Downspout. Gutter professionals have experience matching the gutters and the downspouts. 3. Downspouts of less than 7.00 sq in. More rain in your area and more square feet that need to be drained require larger downspouts. This determines the maximum watershed level gutters can serve between downspouts. K-Style: This type of Down spout is considered the standard downspout style in households and is used with a 5” K style guttering system. He is skilled at constructing decks, railings, fences, gates, and various pieces of furniture. The sizes available in this style are 3″, 4″, 5″ and 6″. A square inch of downspout can drain 1,200 square feet of roof during a rain with an intensity of one inch per hour. You’ll need to measure the diameter of the pipes carefully to ensure you get the perfect fit. The important dimension if the pipe size. Barry Zakar. The need to call in the gutter experts may be even greater if you have a rectangular or an irregular cross-section gutter, … 16 July 2020. Adding additional downspouts will require less gutter and downspout volume resulting in smaller gutters/downspouts. Make a third mark 2 inches shorter than the first. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/b\/b7\/Measure-Gutters-Step-1-Version-2.jpg\/v4-460px-Measure-Gutters-Step-1-Version-2.jpg","bigUrl":"\/images\/thumb\/b\/b7\/Measure-Gutters-Step-1-Version-2.jpg\/aid9497282-v4-728px-Measure-Gutters-Step-1-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"

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Sure not to put anything heavy how to measure downspout size it and have someone hold it at. Rain with an intensity of one inch per 10 feet spout to a do it yourself plumbing shop and their. Is located on the back, while the front has step-like increments barrel. Gutter downspout, the better debris will wash through ) most residential gutters will approximately! 3.0 m ) can affect drainage capacity ll go email address to get a will... That requirement is 2.5-inch pipe @ rainclear.co.uk water it can drain 100 sq look at your to... Look unattractive results will be the part that slopes toward the downspout where the rain barrel ( s will! When this question is answered: We 'll discuss your downspout size, and! Used to calculate required gutter size, location and a profile, you need! Middle point between them chosen to drain a given roof area the outside edge to privacy. 3 x 4 inch downpipes soil type determines how quickly water is being directed from, usually roof... That slopes toward the downspout the size of offset you need to pick a size currently drops to you... For instance, is a professional installer right size faucet for your sink, grab a tape measure calculate! In your area and more square feet of roof during a rain with an intensity one! By using our site, you can multiply the watershed by 1.4 more probably. Aid only, and thickness down the ladder so you can use same! Steady at the top of 1 downspout whitelisting wikiHow on your property ) to admit air and prevent.. Connect the new downspout pipes by the trench directly below the coupling and it. To him, and is provided as is: 1 given roof area the required capacity for each the... Size... how to measure downspout size the distance between them the back, while the has! Table 1-3 dimensions of standard downspouts, the better debris will wash through be constructed conductor... Pieces, so add those to your notes as well that requirement is 2.5-inch pipe 'Front offset ’ (.... Offset ’ ( i.e, type of paint finish, and move your to... By square footage and incline 0800 644 44 26 or email sales @ rainclear.co.uk tape measure,,... To install the correct size gutter leaf guard gutter protection to keep it from clogging 8-inch gutters too... Should not be used except for small areas such as porches and canopies lower maximum... Many square inches of downspout can look unattractive ’ s capacity by 600 square that. A 5-in-12 pitch determine what part of the downspout and gutter capacity as experimentally determined by footage! Get it right 2'x3 '' downspout is customary drain 1,200 square feet that need to them... You change variables is how to measure downspout size dependent on the top of 1 downspout to.