Rough plumbing before slab?

[antinym]

I'm starting the rough plumbing, just the underground drainange stuff. A concrete guy says to me, "How is it that you can start the rough before the footers are dug?"

Is that the normal order of things? What am I missing here?

 

[Leaflessshadetree]

It may depends on the area and type of foundation. Around here I've usually seen the drain tile put in after the footers and walls were poured but before the trench is backfilled.

 

[matt_i]

Typically what I've seen for a house, is the perf drain tile is set next to the finished footing and wall assembly (as above) and covered with stone. To set it in the trench before the concrete is done would mean potential for damage by people building the form, or placing the concrete in the footing, as I would think it would get walked on quite a bit.

 

[glentre]

I think he's talking about plumbing drains, not foundation drains

Glen

 

[Leaflessshadetree]

I think he's talking about plumbing drains, not foundation drains

Glen

Well, that makes a difference. How much plumbing is there underground?
Is a septic system or just the sewer exit?
If this is a slab with various floor drains etc. It's much easier to position the plumbing to match the foundation than it is to position the foundation to match the plumbing.

 

[gregtwojeeps]

Yep, the OP is putting his handiwork at risk doing his piping before the footer is dug. Even with staked flags showing their location, it will make it harder for the footer to get dug by a back hoe if there are too many pipes installed beforehand. Not the normal chain of work progression... for sure....

Normally.... Just dig and pour the footer, lay or pour the foundation walls, grade the floor space dirt, install the rock inside the foundation...then the plumber does his under ground piping and pipe stub ups in the rock for the slab prep pour. The owner or plumber usually sleeves or most of the time, just hand digs under the footer later for the main sewer pipe exit. JMO

 

[Falcon67]

We dont know where he is, so who knows what footer. Here they lay all the pipes and drains well before any concrete gets poured.

 

[readhead]

Around here the stem walls are in place or if it is a mono pour the forms are in place. The slab prep is done and then the plumber and electrician come in and do their work. The grade is cleaned up and the slab is poured.

I don't know how you would pull strings for the wall layout without some kind of stem or form to go to.

 

[FullRaceMerc]

Here they dig & form the footings, but hold off on pouring concrete. Then the plumber runs drains thru the forms & wraps the portion that passes thru the concrete in foam prior to the pour. He might just stub thru the form to connect to later, or complete the layout inside the building. The latter usually being preferred by the plumber.

 

[pmiranda]

Yeah, I wouldn't try to rough in before all the digging is done, but around here "waffle" foundations are not uncommon that requires digging not just around the perimeter.

 

[antinym]

Thanks guys. I think I understand a bit better now. More information:
Central florida. Mono slab. Septic. This is a home addition. 2 sinks, 1 toilet. The plumbing does run though 1 footer.