Need advice please. Just bought a condo in Chicago and wanted to move toilet. I hired the plumber who did the original rehab work because I figured he was familiar with the building. He said it would be no problem to relocate the toilet. okay, fine. He told me we could run pipe under the joists. Great. When I came by to check out the progress the carpenter was livid. The plumber had drilled through 4 joist. He bored 4, 4″ holes through 1 3/4″ X 9 1/2″ joists and ran 3″ pvc. My carpenter tells me 3″ holes are the maximun allowed, and is concerned that over time my floor might bounce and pop my tile floor as well as other things. Carpenter says the span of joists is 10 feet but hard to tell what is going on with the frameing because of the age of the building and number of rehabs it has been through. Should I be concerned about this? How could it be fixed if it is needed? Is this gonna cost me an arm and a leg? Thanks for your time.
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I am not going to disparage plumbers in general, because like any profession there are truley honorable and professional plumbers and there are thoes that make all the rest look bad. I have to say that I have repaired many problems caused by careless plumbers, in my house they didn't just bore though the joists they simply cut the joist in half fight under the toilet.
If the joists are still accesible you could remove the PVC and screw and bolt on plywood supports on either side of each joist then bore thought the whole assembly (in the same place as the orignal hole of course) That would give the joist additional strength against deflection. You really cant just screw the scabs in place they should have several bolts going through the whole sandwich assembly.
I it makes you feel better I had to replace the entire floor in my bath and kitchen because of careless work.
Justus
Justus Koshiol
Running Pug Construction
The perscriptive code requires the edge of holes to be 2" from the edge of the joist.
I would put your carpenter in the same class as your plumber and rely on neither for an opinion. Hire an engineer if you have doubts.
The perscriptive code requires the edge of holes to be 2" from the edge of the joist
It also requires bored holes be no more than 1/3 of joist depth, and not to be int the center third of the span. So a 4" hole is almost an entire inch too much for a 9 1/2" joist, and the poster does not state where in the span the hole is. What exactly did the carpenter have wrong?
Edited 5/1/2003 10:45:11 AM ET by Mugsy
Did he say if this was solid wood joists or TJI type I-Joists? Makes ALL the difference in the world.
Nope. He didn't say alot. I should have just asked for more info. Instead I was peeved at George's response and just quickly pointed out something he didn't mention in calling the carpenter incompetent. Of course you are correct, it makes big difference whether these are dimensional joists or engineered I-joists. I was assuming from his reference to the age of the building that they were dimensional. But I should know better than to assume.
PS glad to see you back. Always enjoyed your posts. Especially when you were calling someone out for a bad post<G>
I don't see where I said the carpenter was incompetent. So be peeved at yourself.
I did say neither he nor the plumber should be relied on for engineering advice. I will stand by that. The only person who should be trusted to come up with a fix for this is an engineer on site.
As far as the hole being too large that is true. I simply pointed out a less obvious problem.
----
Have a nice day, you need one.
George,
Why does he need an engineer, thats your standard answer to almost everything here
Plumber drilled to big of holes through the joist, happens all the time, fixed it several times myself, no need to get an engineer involved
There are many ways to stiffen the existing joist enough or simply replace them if they are accessible by sistering on new one's the lenght of the span and running the line underneath if the space is unfinished.
Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
(I was away vacumming.)
5 minutes of engineering (I don't guarantee the math it is free. Don't care about the material properties. These are close enough. Have not seen the joists or spacing. Have not seen the hole location. ):
1.5 x 9.25 x 10' @16" and 1/360 deflection supports 120#/sq ft.
subtract all but 2" on the edges
1.5 x 5.25 x 10' @16" and 1/360 deflection removes 24#/sq ft.
With a 2" flanges the joists will support 96#/sq ft.
Does not need a repair.
Don't like that method:
2x8 will span that distance @ 16" and 40#/sqft. 1/3 hole (1/3*7.27) leaves flanges of 2.42. 2x10 with 2.42 flanges allows a 4.42 hole.
Does not need a repair.
Ain't engineering great.
How much does the floor need to move before his tiles start popping off or breaking? Wasn't that his initial concern, not how much weight the floor would support but how springy it was going to become.
First Iraq, then France, then Hollywood!
Whoa guys! before you start breaking out the equations, a good point was made that we don't know where the holes are, or if they are centered on the joist. If they are in the center and close to one edge or the other you have a seroius problem, if centered and towards the end it might be a simple fix.
But take it easy on each other, it's not like someone is saying that YOU cut the joist.
A bath room floor should have as little deflection as possible, especially around the toilet. where (if a wax seal is used) the seal can be broken by shifting floors. Justus Koshiol
Running Pug Construction
I am not on site. I have no idea what he NEEDS to do. None of us do.
If all my assumptions are correct, he has no problems if he installs a subfloor to the tile/thinset/grout manufacturer's specs and then tiles.
They only require 1/360 joists @40#/sqft and that is what I checked for.
Wow! gee thanks for quick math that may not even be close to accurate based on the stituation and the substantial amount of missing detail.
Bathrooms are heavy, floor deflection must be minimial, all the engineering in the world will not change the fact that a 4 in. hole in 4 successive 2x10 joists is a bad idea and should most likely be addressed in some fashion.
Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
You implied it, as usual. I didn't see where the carpenter was dispensing engineering advice. And as CAG said, there is no need for one on this fix.
I imply nothing. You infer it.
See my 5 minute engineering comment above.
No he didn't state one way or the other
I would AS$ume it is standard lumber because he said the condo had been through several reno's leading me to belive it was an older home.Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
Should I be concerned about this? Yes
How could it be fixed if it is needed? Depends on how accessible to joist is, is there any electrical lines running through the four the joist he cut
Is this gonna cost me an arm and a leg? No it shouldn't the plumber screwed up and should take responsibility.
Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
Yes, be concerned but not enough to jump out of a window.
I would do a little re-inforcement at the bottom with sistering and let it fly unless your inspector needs more. George is a little off on the side again, especially with suggesting that you put the carpenter in the same class as the plumber. This carp is showing real integrity to be upset at what the plumber did.
As for an objective view on what is right, see the attachment.
Excellence is its own reward!