# It all looks normal



## ICE (Oct 10, 2011)

enough until you realize that it is all 4" dia. pipe.  The second picture is the drain pipe for a kitchen sink.


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## north star (Oct 10, 2011)

** * * **

They CAN still go above the code and install the 4" dia. pipe

can't they?      .......Also, do they use pipe sleeves or relieving

arches out there, in the perimeter footings?....[ refer to

P2603.5, `06 IRC ].

** * * **


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## Builder Bob (Oct 10, 2011)

They can, but might not be a great idea...... the water flow drastically slows down for the same volume of water/wastes when pipe is upsized. Could create more opportunities for blockage and back-up in plumbing pipes because more water is needed to keep pushing the crap downstream...


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## Pcinspector1 (Oct 10, 2011)

Must be trying to put roto rooter out of business!

pc1


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## ICE (Oct 10, 2011)

north star said:
			
		

> ** * * **They CAN still go above the code and install the 4" dia. pipe
> 
> can't they?      .......Also, do they use pipe sleeves or relieving
> 
> ...


If the pipe passes through the footing it gets an arch or a sleeve.  So I'm going by memory here, but a sleeve must be two sizes bigger that the pipe and the annular space shall be sealed.  If a pipe is used as the sleeve, what should be used to seal the annular space?

What do you think of this method?  Wrap the pipe with foam as thick as three pipe sizes and it's done.  Is the foam too dense to collapse if there is settlement?


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## ICE (Oct 10, 2011)

Builder Bob said:
			
		

> They can, but might not be a great idea...... the water flow drastically slows down for the same volume of water/wastes when pipe is upsized. Could create more opportunities for blockage and back-up in plumbing pipes because more water is needed to keep pushing the crap downstream...


It seems to me that I remember the UPC used to say that a horizontal waste pipe can't be more than two sizes larger than the required size. The scouring action is negated when there is a dribble in a big pipe.  It runs straight down the center without sloshing back and forth.  There was also something about excessive pitch for the same reason.  There's more to being a plumber than smelling good.  There is a sweet spot for running sh!t down a pipe.


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## RJJ (Oct 11, 2011)

Is the cast iron pipe no hub?


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## ICE (Oct 11, 2011)

RJJ said:
			
		

> Is the cast iron pipe no hub?


Yes it is.


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## north star (Oct 11, 2011)

> "If a pipe is used as the sleeve, what should be used to seal the annular space?"


A material that is approved by the AHJ.



> "It seems to me that I remember the UPC used to say that a horizontalwaste pipe can't be more<BR>than two sizes larger than the required size.
> 
> The scouring action is negated when there is a dribble in a big pipe. It runs
> 
> ...


I agree!......Also, the use of "low flow" type water closets will not facilitate thescouring and transportation process when the larger sized piping is used.





> "what do you think of this method? Wrap the pipe with foam as thick as three pipe sizes and it's done.Is the foam too dense to collapse if there is settlement?"


I would not recommend the use of foam wrapping as it does not / will not provide

any protection to the piping......By the time any loads are imposed on the foam,

...because it is attached directly to the piping, the loads are now imposed on the

piping as well.

Sooooooo, ...was this installation a PASS or FAIL?

*& & & &*


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## Keystone (Oct 11, 2011)

As BB and a few others pointed out, can't have the water run away from the solids. Would not allow it.


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## mtlogcabin (Oct 11, 2011)

2009 IRC

P3005.4 Drain pipe sizing.

Drain pipes shall be sized according to drainage fixture unit (d.f.u.) loads. The size of the drainage piping shall not be reduced in size in the direction of flow. The following general procedure is permitted to be used:

P3005.4.1 Branch and stack sizing.

Branches and stacks shall be sized in accordance with Table P3005.4.1. Below grade drain pipes shall be not less than 11/2 inches (38 mm) in diameter. Drain stacks shall be not smaller than the largest horizontal branch connected.

TABLE P3005.4.1

MAXIMUM FIXTURE UNITS ALLOWED TO BE CONNECTED TO BRANCHES AND STACKS

2009 UPC

703.1 The minimum size of vertical and/or horizontal drainage piping shall be determined from the total fixture units connected thereto,.....

703.2 Table 7-5 shows the maximum number of fixture units allowed on any verticle or horizontal drainagepipe, building drain, or building sewer of a given size....

I don't find any specific code requirement prohibiting the larger drain lines. I agree larger may not be better in a building drainage system but how do you back it up with the code?


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## north star (Oct 11, 2011)

*% % % %*



> "I don't find any specific code requirement prohibiting the larger drain lines. I agree largermay not be better in a building drainage system but how do you back it up with the code?"


As " Papio " has recently referenced, by using the god section of the IRC......From Section R104.11of the `06 IRC: *Alternative materials, design and methods of construction and equipment.*

The provisions of this code are not intended to prevent the installation of any material or to prohibit

any design or method of construction not specifically prescribed by this code, provided that any such

alternative has been approved.........An alternative material, design or method of construction shall be

approved where the building official finds that the proposed design is satisfactory and complies with

the intent of the provisions of this code, and that the material, method or work offered is, for the

purpose intended, at least the equivalent of that prescribed in this code........Compliance with the specific

performance-based provisions of the International Codes in lieu of specific requirements of this code

shall also be permitted as an alternate."

*% % % %*


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## mtlogcabin (Oct 11, 2011)

How is it an alternate when a maximum drain size is not limited?


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## north star (Oct 11, 2011)

** * * **





> "How is it an alternate when a maximum drain size is not limited?"


Because of the "low flow" type water closets, there is not enough water [ themedium of transportation ] to deliver the solids to the point of connection

to the sewer main......3" sized piping can handle the volume of wastes in most

residential applications.



** * * **


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## mtlogcabin (Oct 11, 2011)

TABLE 710.1(1)

BUILDING DRAINS AND SEWERS

footnote a.  The minimum size of any building drain serving a water closet shall be 3 inches.

According to the table the steeper the slope the more fixture units it can handle. 3" at 1/8 per foot 64 1/4 per foot 42 and 1/2 per foot 50

Just how many solids are in a tub, sink, shower, washing machine, or dishwasher drain that will settle in a 4" building drain and cause problems? In other words I don't think I would make them tear it out without seeing what the larger lines are serving and what potential problems there may be.


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## north star (Oct 11, 2011)

** * * **

mtlogcabin,

I do not know of any solids in or from the tub, sink, shower, washing

machine and only very minimally [ maybe ] from a dish washer......The

largest concentrations of solids will come from the water closets.....I do

not have any scientific data to support the idea of there is less water

transporting the solids, but if it takes two or more flushes to remove

the contents from the water closet bowl(s), ...I would contend that

there is insufficient amounts of water to adequately transport all

of the solids completely to the main sewer line connection......Also,

as you already know, ...the larger sized piping will have more

surface area for the water to spread out over, thus reducing the

level of water for the transportation process.

** * * **


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## ICE (Oct 11, 2011)

north star said:
			
		

> Sooooooo, ...was this installation a PASS or FAIL?
> 
> [/font][/size][/color]*& & & &*


Fail.   There were a few flat spots.  Bands needed to be tightened.  Nothing major.  By the way, the waste pipe has to pass inspection before I allow the wrap and this picture was taken between under-floor plumbing and footing inspections.  When I do the footing/slab inspection I expect the pipe that will be in contact with concrete to be well protected and that means no black and white bands as you see here.

I have been using the 3 sizes bigger with foam wrap as sleeves for some time now.  I think that an inch and a half of foam will have enough give to protect the pipe.  A great many have been built embedded without a lot of problems.  I'll kick it around with my engineer.


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