Dougster
New Member
There are already threads here on this topic such as "Low flush toilets causing sewage pipe clogs???"
but here’s an interesting recent (2015) MSc thesis from Kansas State U suggesting further study may be needed:
BTW California has a partial exception to the 1.28 gpf maximum:
I have an old house with 58 y.o. toilets and 4 inch waste lines.
Have any plumbers here been called on to certify that low flush toilets will not work in an older residential DWV system?
but here’s an interesting recent (2015) MSc thesis from Kansas State U suggesting further study may be needed:
http://krex.k-state.edu/dspace/bitstream/handle/2097/19223/ReneLe2015.pdf;sequence=1
DRAIN LINE CLOGS WITH A 1.6 GALLON PER FLUSH WATER CLOSET
…
CONCLUSION
…
“The information in Chapter 3 highlight that further research about pipe line clogs should be conducted before enforcing water closets that use less than 1.6 gpf. Manufacturers have ensured that waste will clear the bowl, but there is data to suggest the amount of water from a 1.6 gpf water closet cannot clear 30 feet of four inch PVC DWV piping at 1/4" per foot slope, and that a minimum of four additional flushes are necessary to clear the pipe line.”
DRAIN LINE CLOGS WITH A 1.6 GALLON PER FLUSH WATER CLOSET
…
CONCLUSION
…
“The information in Chapter 3 highlight that further research about pipe line clogs should be conducted before enforcing water closets that use less than 1.6 gpf. Manufacturers have ensured that waste will clear the bowl, but there is data to suggest the amount of water from a 1.6 gpf water closet cannot clear 30 feet of four inch PVC DWV piping at 1/4" per foot slope, and that a minimum of four additional flushes are necessary to clear the pipe line.”
BTW California has a partial exception to the 1.28 gpf maximum:
http://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=200920100SB407
…
1101.7. This article shall not apply to any of the following:
(a) Registered historical sites.
(b) Real property for which a licensed plumber certifies that, due to the age or configuration of the property or its plumbing, installation of water-conserving plumbing fixtures is not technically feasible.
…
1101.7. This article shall not apply to any of the following:
(a) Registered historical sites.
(b) Real property for which a licensed plumber certifies that, due to the age or configuration of the property or its plumbing, installation of water-conserving plumbing fixtures is not technically feasible.
I have an old house with 58 y.o. toilets and 4 inch waste lines.
Have any plumbers here been called on to certify that low flush toilets will not work in an older residential DWV system?
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