Quick toilet drain slope question

[JuanSigned]

I just put in a new toilet drain line that measures 78" horizontal. Using my trusty fractions calculator I figured that a 1/4" per foot drop should be 1 5/8". However my final slope ended up being 1 3/8", so basically its off by 1/4" over the entire 78" length. The interwebs are confusing, some say 1/4" per foot is the minimum others say 1/8" I'm closer to 1/4 that 1/8, but it's still off.

Is this enough of a problem to warrant tearing it out and doing it over?

 

[FullySprinklered]

Leave it; it's fine. Some areas let you squeak by with 1/8" per foot in a tight.

 

[Sponsor]

 

[Dj2]

It's 1/4" minimum.

1 inspector out of say 10 will fail you and will ask to see 1/4" slope all the way. Don't forget that plastic pipes have slight curves, something else to worry about.

 

[JuanSigned]

It's 1/4" minimum.

1 inspector out of say 10 will fail you and will ask to see 1/4" slope all the way. Don't forget that plastic pipes have slight curves, something else to worry about.

The point about the pipe having curves is well taken. When I bought the pipe I picked out the straightest piece from the pile, but I've never seen one that was perfectly straight. So there must be an acceptable range of slopes from 1/4" to ?/?" to account for those unavoidable curves.

 

[Reach4]

I don't know, but you might consider adding extra hangers to avoid sag. Perhaps you can lay a laser pointer along side and detect any sags.

 

[Jadnashua]

Is the pipe three or four inch diameter?

 

[JuanSigned]

Is the pipe three or four inch diameter?

It is a 3" ABS pipe

 

[Jadnashua]

On 4" and larger, you can get away with slightly less slope...don't think I'd try it with 3".