Technical Booklet N Drainage·Page 31·4.7
Gutter joints watertightness
Gutter joints must remain watertight during normal operation. Rainwater pipes inside buildings must pass the test in paragraph 2.4, and rainwater drains (excluding soakaways) must pass either test described in paragraph 3.15.
Gutter joints should remain watertight under working conditions. A rainwater pipe inside a building should be capable of withstanding the test described in paragraph 2.4. A rainwater drain (other than a soakaway) should be capable of withstanding either of the tests described in paragraph 3.15.
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