How To Size Box Gutters

Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.

How to size box gutters.

Must have a constant slope between 1 40 and 1 200. 5 inch 5 520 square feet. For example by going up to a 6 inch from a 5 you are increasing the amount of water the gutters can hold by 40. Gutters come in k style and half round style.

If a roof s various drainage areas call for different size gutters go for the biggest one k style. 5 inch 5 520 square feet. If the adjusted square footage is equal to or less than 2 500 feet 760 m choose 5 in 13 cm half round gutters. Down pipe must be vertical from sump not to the side minimum sump length is 400mm.

While a smaller commercial building might be able to get away with 5 inch box gutters we generally recommend that you start by looking at the 6 inch sizes. Sizes the depth shown of the box gutter is the depth at the upstream end. If a roof s various drainage areas call for different size gutters go for the biggest one k style. Calculate the necessary scaling factors to scale these dimensions to the flow we want.

Box gutters must be straight no bends. Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage. 6 inch 7 960 square feet. 6 inch 7 960 square feet.

For square footage up to 3 840 feet 1 170 m use 6 in 15 cm half round gutters. Pick any size box gutter that fits on the relevant graph and determine the depth and the rain water head sizes. Then use the chart below to see what size gutter you need.