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a4z2b01
Jul 31, 2009, 02:38 PM
On my bubble level, where would the bubble be on a quarter inch drain slope?. I have heard a quarter bubble crossing the line. How much area is determined by the 2 black lines on a level.. how much slope if the bubble was a little off or way off?

massplumber2008
Jul 31, 2009, 03:41 PM
Hi A4z2b01:

I've never used the "break the bubble" method of pitching pipes. I have always used a PITCH LEVEL. These are expensive and usually hard to come by but you can make your own pitch level by following the information below.

For 3" pipe or smaller you want 1/4" pitch per foot of pipe. For 4" pipe or larger you want 1/8" pitch per foot.

To make this work so you are consistent in pitching 3" drain pipes, for example, you want take a 2 foot level and tape a 1/2" nut (or block of wood) on one end of the level (gives 1/4" pitch per foot). Set the level on the pipe so that the lifted end is toward the low end of the pipe and set the pipe so that the level reads perfectly level. This should guarantee a pretty consistent pitch to your pipe.

If you use a 4 foot level and want 1/4" pitch per foot you would use a 1" block of wood. If you want an 1/8" pitch per foot and you are using a 4 foot level you would tape a 1/2" block of wood, etc...

Hope that all made sense... ;)

MARK Attached Images https://www.askmehelpdesk.com/attachments/plumbing/22563d1248778560-plumming-fall-a1.jpg

speedball1
Aug 1, 2009, 11:56 AM
On my bubble level, where would the bubble be on a quarter inch drain slope?...I have heard a quarter bubble crossing the line. How much area is determined by the 2 black lines on a level.. how much slope if the bubble was a little off or way off?

I've always used a "break the bubble" when roughing in drainage.
For 3" and over I just crack the bubbles edge, that gives me about 1/8th inch to the foot. A little more bubble and I have 1/4". If I have to get serious, like running reefer chases in a super market at zero tolerances, I use a transit. Regards, Tom

jlisenbe
Aug 1, 2009, 03:48 PM
Mass, I HOPE I can remember that trick.