Minimum Gutter Fall Nz

This is an external gutter so using clause e1 figure 15 plot 38 40 m plan area on the vertical axis.

Minimum gutter fall nz.

There are three new zealand building code clauses that must be applied to internal gutter design. The larger measurement of the two on a case by case basis should be taken. The largest plan area is area a at 38 m. For internal gutters it is recommended that the proportion of base width to height be 2 1.

Outlets need to be protected from blockage. E1 as1 has no minimum fall for internal gutters e2 as1 minimum fall must be 1 100 10 mm per metre which is often unachievable. Clause e2 external moisture requires that roofs. New zealand building code clause e1 figure 15.

Effect of gutter fall on drainage capacity. Gutter fall all gutters must have a minimum fall of 1 500 2 mm in 1 m the cop recommends 1 200 5 mm in 1 m as it will improve drainage and self cleaning. Clause e1 surface water requires that construction protects people and other property from the adverse effects of surface water. Circular 70mm rectangular min.

Use table 3 1b section 3 1 4 of technical manual to determine the rainfall intensity to be used. Gutters will be the same size for all the roof so use the largest plan area to work out the appropriate size gutter. 1 500 2mm in 1m minimum downpipe. Catchment area per downpipe based on the above flow capacity is given in table 3 1g.

Clause b2 durability requires 15 year minimum durability. A fall of 1 60 provides even better drainage. The minimum recommended height for commercial internal gutters is 70mm or 1 60th of the overall length. Minimum gutter slopes should be applied to all internal gutters so that.

Cross sectional area of 4125mm smallest dimension at least 50mm. Where the gutter discharges into an outlet pipe it must be a minimum diameter of 75 mm and sized to suit the overall gutter capacity. A fall to the outlet is always maintained so that all water is removed some inaccuracy in construction will not negate the fall some sagging in the gutter over time can be accommodated without compromising the drainage.