Serving Minnesota and Wisconsin Since 1977

Call  or  Text 763-537-4849

Different Draintile, Different Results

0:09for the purpose of retrofit sub soil

0:12drainage commonly referred to as

0:14basement waterproofing the Minnesota

0:16uniform plumbing code specifies drainage

0:18conduit with a minimum three inch

0:20diameter the code also gives officials

0:23the authority to allow other types of

0:25drainage conduit as long as they meet

0:27the minimum standard here we will

0:30examine the size of the opening flow

0:32rate and holding capacity of four

0:34different types of drainage conduit the

0:37intent is to suggest a way to determine

0:39if an alternative type of drainage

0:41conduit meets or exceeds the minimum

0:44code will also consider performance

0:46characteristics based on how the

0:48different styles of drainage conduit are

0:50installed we will use standard flow

0:52rates as found in manufacturers

0:54published documents where available

0:56three-inch corrugated drainage conduit

0:59with an opening of 7.06 square inches

1:02has a flow rate of 35 gallons per minute

1:04the corrugations caused friction as the

1:07water flows through affecting flow rate

1:09the corrugations also hold water so it

1:11does not drain completely plus it’s

1:13flexible which makes it difficult to

1:16install at a continuous downhill slope

1:18once again affecting flow rate the

1:20holding capacity is one and

1:22three-quarters leaders three inch rigid

1:26PVC drainage conduit also with an

1:29opening of 7.06 square inches has a flow

1:32rate of about forty four gallons per

1:34minute it follows a smooth downward

1:36slope to the sump basin and drains

1:38completely the holding capacity of a one

1:40foot section of three inch PVC drainage

1:42conduit is one and one half liters the

1:46in slab drainage conduit is a

1:48proprietary product and has no published

1:50flow rate its opening is approximately

1:525.25 square inches because it sits on a

1:56footing which is supposed to be level it

1:58will have a lower flow rate than either

2:00three inch corrugated or three inch

2:02rigid PVC drainage conduit also it may

2:05not drain completely due to the lack of

2:07a downhill slope the holding capacity is

2:09just over one liter2:11the multi flow drainage conduit has a

2:14published flow rate of twenty nine

2:15gallons per minute each of the five

2:17pipes as an opening of one inch giving

2:20the product a total opening of three

2:22point nine to seven square inches it’s

2:24important to note that the flow rate

2:25figure is arrived at with the pipe under

2:28ten pounds per square inch of pressure

2:30yet the multi flow pipe is not installed

2:33as a pressurized system this product is

2:36also intended to be installed level in

2:38order to have access to the cleanups

2:40flow rate is affected by the corrugation

2:42and lack of downhill slope unpressurized

2:45we assume the flow rate in reality is

2:48significantly lower than the published

2:50rate we sealed the multi flow drainage

2:53conduit in order to check holding

2:54capacity which is one-half liter the

2:58Minnesota uniform plumbing code gives

3:00officials the authority to allow other

3:02types of drainage conduit as long as

3:04they meet the minimum standard it

3:06appears the minimum standard is drainage

3:09conduit with an opening of 7.06 square

3:12inches a flow rate between 35 and 44

3:15gallons per minute and a holding

3:17capacity between one and one-half and

3:19one and three-quarters leaders in order

3:22to achieve these flow rate drainage

3:24conduit must be installed at a

3:26continuous downward slope while speaking

3:29with a manufacturer we were told

3:31drainage conduit installed level has a

3:33flow rate of zero to sum up it appears

3:37two of the four drainage conduits have

3:39significantly lower flow rates because

3:41of their smaller size and level

3:43installation which again yields a flow

3:46rate of zero as a result we believe

3:49those two products do not meet code and

3:51should not be allowed