sewer pipe fall?

darragh_haven

I'm currently doing the sewers around my house, but a 25 meter section, between 2 AJ's, has a fall of about 1:120 due to hitting rock. The rest is done at 1:60.
Would I be ok with this or am I just asking for trouble?

Poor Uncle Tom

For a smooth wall 100mm diameter pipe the minimum recommended fall is 1:60. You can fall 150mm diameter smooth wall pipes at less of a fall but nowhere near 1:120.

Also 25m between AJ's is excessive.

darragh_haven

Poor Uncle Tom wrote: »

For a smooth wall 100mm diameter pipe the minimum recommended fall is 1:60. You can fall 150mm diameter smooth wall pipes at less of a fall but nowhere near 1:120.

Also 25m between AJ's is excessive.

It's 100mm smooth wall. And there is another straight line AJ half way between the 2 that are 25 meters apart.
I have my dads 3 ton mini digger with a breaker but the rock is like flint. I'd have to break 200mm at the lower AJ..... Don't think it'd do it.

gman2k

You're going to need a bigger digger!

sydthebeat

darragh_haven wrote: »

I'm currently doing the sewers around my house, but a 25 meter section, between 2 AJ's, has a fall of about 1:120 due to hitting rock. The rest is done at 1:60.
Would I be ok with this or am I just asking for trouble?

is it not possible to redesign the network without going near the bedrock?

darragh_haven

sydthebeat wrote: »

is it not possible to redesign the network without going near the bedrock?

The whole hose is on.bed rock. Gave an hour belting it with the breaker today, and I've got it to, 1 to 80..... I think it'll have to do. 3 Ajs in that section so I should be covered

VonLuck

You might find page 14 of the building regulations useful.

http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,24906,en.pdf

gman2k

darragh_haven wrote: »

The whole hose is on.bed rock. Gave an hour belting it with the breaker today, and I've got it to, 1 to 80..... I think it'll have to do. 3 Ajs in that section so I should be covered

Give it another hour and do it right! 1:60 - you have the machine, you have the time. You won't be able to revisit this later!

darragh_haven

gman2k wrote: »

Give it another hour and do it right! 1:60 - you have the machine, you have the time. You won't be able to revisit this later!

I sorted it out between yesterday evening and this morning..... 3 more hours breaking. As you said, can't revisit it when there is a footpath or tarmac over it.
It wasn't entirely yer coaxing that made be stick at it. It was;
Old fella: what fall is it suppose to be?
Me: 1:60
Old fella: what is it?
Me: 1:80 maybe 1:85 in places.
Old fella: (silence) (raised eyebrow) (walked away)
Me: back on the machine with the breaker hopping. (nothing worse than the "i told ya so" look if the **** backed up)

muffler

darragh_haven wrote: »

I sorted it out between yesterday evening and this morning..... 3 more hours breaking. As you said, can't revisit it when there is a footpath or tarmac over it.
It wasn't entirely yer coaxing that made be stick at it. It was;
Old fella: what fall is it suppose to be?
Me: 1:60
Old fella: what is it?
Me: 1:80 maybe 1:85 in places.
Old fella: (silence) (raised eyebrow) (walked away)
Me: back on the machine with the breaker hopping. (nothing worse than the "i told ya so" look if the **** backed up)

The voice of experience vs the exuberance of youth