Branz Internal Gutter

Branz bulletin 556.

Branz internal gutter. Gutters and downpipes are the most common method of disposing of surface water from buildings. Outlets need to be protected from blockage. E2 as1 specifies no end laps for membrane lined internal gutters and that metal gutter laps are welded. Live in the us and houses built in the 70s have this internal gutter system that s failing all over the neighborhood.

Checked annually for any damage or deterioration to the gutter lining cleared to remove debris leaves etc. Statutory requirements rainfall. When sizing an internal gutter the gutter should be divided into sections each section is the length of gutter between the downpipe and the high point on one side of the downpipe. Consumers can call the consumer helpline 0900 5 90 90 calls cost 1 99 per minute plus gst.

Branz search and locate tool the branz digital helpline a useful directory of building and construction information in new zealand. Internal gutter construction gutter construction varied from a simple shallow trough or v like a valley detail to a tapered valley laid over firred framing to give a fall figures 5 and 6. Ongoing maintenance of internal gutters is as essential as good design and. 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.

However significant inconvenience damage repair cost and health issues may occur if water from the gutter gets into the building structure and or the space below. Design for a 10 minute rainfall intensity for the location with a recommended minimum design intensity of 200 mm hour rainfall intensity is for a storm with a 10 probability of occurring annually. Sections are sized according to the roof catchment and the largest calculated size is used for the whole gutter. My house is a 2 story california split style though i live north of seattle ha and has exposed rafter ends about 20 inches or half a meter long supporting the exposed and painted plywood decking with an angle cut on the exposed rafter ends.

To ensure that water is safely disposed of gutters and downpipes should be sized and installed so that the expected amount of water can be controlled with minimal chance of water entering the building and minimal risk of uncontrolled spillage this bulletin covers. Often the outlet to the valley gutter discharged over a small portion of roof before being contained by the eaves gutter figure 7. Internal gutters also known as box gutters are seen as an easy solution to the collection and disposal of roof water. To make internal gutters as safe and durable.

Every internal gutter must have at least one outlet and one overflow. Figure 1 internal gutter design.