PVC Plumbing too high; need to lower

I'm gutting & redoing 2 bathrooms that adjoin each other; together they comprise a floor space of about 11' x 11". There are 2 toilets, 2 sinks, a tub & a shower stall that all plumb into a main drain located directly underneath in an unfinished basement.

The wall separating these 2 bathrooms is NOT supported properly underneath. The original construction created about a 5'x6' area with no joist support. Why? I can only imagine the idiots decided to plumb all these fixtures as high to the basement ceiling as possible, and doing so interfered with the joists; so they removed them.

I want to finish tile both bathroom flloors, but I need to ensure proper subfloor support first. I could try to fashion a bit more support underneath this 5'x6' area, but I'd definitely have a more substantial subfloor if I paid a plumber to lower all the pvc that plumbs into the drain line, so that I could install additional joist support.

Assuming I am right, and it is possible to lower these pvc connections another 12"-to-24" down, what do you think a reasonable charge for this would be? Put another way, I can't imagine it taking longer than a day for one man to cut and reattach everything. What would a plumber charge for a day?

Depends on where you live and how it is set up which we can not see.

With corners cut like that I would imagine there were other corners cut also.

While plumbers get paid for time worked they also get paid for their knowledge and skill.

If you are going to do the floor support work then get a plumber to come out and check the previous work and see if it is O.K. and get an estimate. Get 2-3 estimates.

price

Some of my worst jobs have been the ones where the customer says, over the phone, "it is so easy it should only take, (insert a time), to do it" and expects me to give them an estimate based on that assessment. When I tell them it will be at least $***, but could be more, based on the actual time to do it, they go brain dead as soon as they hear the number, and do not understand the "or more" part. Then they are quite upset when the final bill is more than "what was quoted", even though their job was nowhere similar to what they described. Call a local plumber, or two or three, and get prices from someone who actually sees the scope of the work.

Thanks. I plan on calling for estimates. That said, what would you expect a plumber to charge for a day's work? Just trying to get a ballpark .

professionals charge a reasonable rate. It is based on time spent performing the work. Rates current in your area depend on professional costs in your area, and on the cost of running a business, in your area. In your area there is bound to be some information available that you as a member of the public can ask for, perhaps from the professional and regulatory association that Master Plumbers all must belong to. They can guide you as to the range of what might be deemed a (minimum) reasonable rate that must be billed to remain in business.

Plumbers are in competition against each other, so there is nothing keeping rates high unecessarily. Pay what they ask to be paid.

David

Where I live, a plumber and helper costs about $115/hour if that helps. Sometimes a job rate ends up being better for you, but then if they figure 4-hours, and it takes 3, it's still the same price. On a job rate, if they figure 4-hours, and it takes 5, they eat the extra. On an hourly rate, it's whatever it takes.

I could be wrong here....but it seems like the first estimate you need is that of a carpenter/structural engineer.

the plumbing could be a piece of cake compared to laying in or sisterings joists.

you may need some jack support as well.

Sure right about that. The "carpenter/structural engineer" looked at it last night. Luckily I have a friend that's finished gutting & rebuilding a summer house, and has a finished frame on a two room addition for it already inspected. When I finally realized how poorly the floor surrounding the plumbing was designed, he was nice enough to stop by. And yes, in 2 weeks when he returns, he's bringing a floor jack