How To Determine Gutter Spread

If relocating an intake recalculate q for the new drainage area s and calculate new values of spread.

How to determine gutter spread.

Adjusting for pitch and rainfall. Kc 0 56 0 376 for compound cross slopes a trial and error procedure is used to compute d in the gutter sw and sx sections separately. Divide the inch per hour watershed of the roof by the 5 minute rainfall intensity. Measure from the chalk mark to the opposite corner of the gutter making another chalk mark and moving the ladder again if necessary.

From this depth and cross section geometry the gutter spread is computed. Run the tape measure from 1 corner of the gutter as far as you can go toward the opposite corner. Ask gutter suppliers what size gutters will be needed to handle that amount. T flow width.

If you still do not see your gutter style then order sizing samples 3 sizes per box to determine which size gutterbrush best fits your gutter. Q flow in gutter in cfs cms z reciprocal of the cross slope. S longitudinal gutter slope. E 0 ratio of depression flow to.

If your gutter style and measurement matches one of the images click the corresponding button above to view more information and place your order scroll down to see additional gutter styles. Determine the ratio of the width of flow in the depressed section w to the width of total gutter flow t using. Compare calculated spread to the allowable spread. The following procedure is used to design curb inlets on grade.

A depressing depth. Make a mark with chalk and record the measurement. N manning s coefficient. S longitudinal slope.

S x roadway cross slope. How do you calculate gutter size. Find spread t given gutter flow q. If spread exceeds allowable limits relocate or resize the intake or add an additional intake.

That is how much rain a roof can drain during the most intense rainfall. D flow depth at curb. Once you know the total square footage of drainage for each gutter you ll need to adjust for the following two factors. That will show how much water a gutter will have to drain.

You can measure pitch with a 2 foot level and a tape measure. Step 1 determine input parameters including longitudinal slope s cross slope sx gutter flow q and manning s n. Compute depth of flow and ponded width t in the gutter section at the inlet.