I am rough plumbing a house I’m building for myself. I know what the codes say regarding hole size in studs but can’t find any information on holes in top and bottom plates. Thanks in advance for the help.
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according to many plumbers, you can remove the top plates...
and wall plates...
and floor plates.
cut the size you need for the pipe and add a plate to protect from DW screws.
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I had a plumber come and check my work and he saw where I had notched a plate for a 3"dwv pipe. He mentioned that a lot of inspectors didn't like to see that. I want to make sure my inspector isn't going to make me redo anything.
Holes are sized for the pipe mostly, 1 1/2" use 2" bit. 2" use 2 9/16", 3" use 3 5/8".
Use the metal nail gaurd plates on the side of the studs, and top and bottom plates.
My only real potential problem is with the 3 5/8 hole that I have already drilled in a double top plate. I need to put in a waste t between floors to drain a water closet. I drilled it too close to the rim joist so now I either have to enlarge it or simply cut out the front (which would be alot easier). My walls framing is stacked so I know the top plate is not load bearing. I know there is no problem doing this, but I want to make sure my building inspector won't balk. He has been none too helpful.
I have another related question about closet flange installation. Because space was so tight I used a 3 inch street elbow and glued the socket side inside the closet flange. Looking closer at the code, I think that may be illegal. I am from New York, so I am going by the NY state code book. Thanks.
The nail guards will help strengthen the area but if you want a stronger plate just go to a thicker/bigger/longer one. The thicker one will make a bulge in the drywall so you might want to take some wood off so it is flush. It's pretty common to have nail guards in a lot of areas. Especially in remodels. the last thing you want is a drywall screw hitting something it's not supposed to hit.
Alot of code issues are subject to the personal views of the inspector.
You neglected to tell us the size of your plates.
I typically frame "wet" walls in 2 x 6 so that I don't run into this situation.
J. D. Reynolds
Home Improvements
This is a two story home and the "wet wall" I am referring to abutts a staircase. Coming from the basement up to the first floor and the first floor up to the second I used a 2x8 top and bottom plates. I doubled the floor joists framing the stairwell openings. 7 1/4" minus 3" gave me 4 1/4" to work with while still being inside the wall.
By the way, I did just enlarge the hole a little and it worked out fine. Thanks for the help.
As far as I know, you can completely cut through a plate but keep in mind that it needs to be firestopped (we usually use "Rock Wool" on larger holes) and if its a bearing wall around here (metro Detroit) we're required to place a 16 guage steel plate across the opening in the plate.
As a structural engineer, I have a different take on this question than a plumbing professional would. It is NOT always OK to completely, or even partially, cut through a plate. It all depends on what sort of load, if any, this plate is supposed to resist. If this is a non-bearing wall and the plate is not acting as a structural collector or a chord, then it may be OK to cut. There are lots of other cases where it may be OK to cut, but then there are a lot of cases where it's definitely NOT OK to cut.
I completely agree with you. I have an example as to why you shouldnt chop up a bearing wall.
The house were finishing now. This bearing wall was cut completely in three places by plumbewrs and HVAC guys.
When I bought the house the ceiling formed a "U". This wall had a double joist under it with 6 inches in between the joists to facilitate running the above items which meant the wall essentially bore on the subfloor.
Over time the floor rotted out and what a disaster.
When we repaired the wall we would not allow the HVAC guy to use that wall at all.
I simply stated that in the town I work you're allowed to chop the plate as long as its straped with 16 guage metal (which personally I dont see how that would restore structural integrity).
You can cut the top plate right out. The hvac guys have to do it like that every day.