So the HVAC guys come in a cut out a 4″ long section of an exterior wall plate so they could run a 4″ sheetmetal dryer vent pipe up to the roof. This left the wall essentially in two pieces, held together only by the OSB sheathing. Of course we the framers got called back to fix it. My coworker (the journeyman) had no idea how to approach it; he had never seen anyone do something so stupid! I grabbed two USP 18″ flat metal straps and nailed one across each plate (top and double) with as many 8d nails as each strap would hold, bridging the gap. Then I cut a 14.5″ 2×6 block with a notch for the pipe and nailed it between the joists and to the plates. It still seemed awful weak even with all the reinforcement, but it was the best I could do. Does anyone have any comments on how to approach this if it ever happens again? An ideas or comments from an enginnering standpoint? I don’t know why they didn’t just vent it straight out to the outside, and I wish I had a picture so you’d all know how NOT to do it!
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Situations like this are best dealt with in the planning phase.
Who ever was "designing" the job should have the specs for all appliances and thier venting or piping requirements.
If needs be then a flue chase should be framed in and the mechanics should be informed to use it.
The 5 p's Prior planning prevents pisz poor performance.
Designers need to realize that a little research before hand, and an eraser and a pencil are alot more cost effective than a sawzall and some cobbled up framing patch.
On the other hand a good mechanic should not be doing this kind of thing to the structure unless he is specifically told to.
I am a big proponent of making people who should know better fix their screwups, But this is not always possible, so at the least, you should make a enough of a fuss about it so they remember the next time.
Mr T
Do not try this at home!
I am a trained professional!
Next time spec oval pipe in the walls. It is around 2"x6" so you can center it in the plates. Dryer vent pipe (plastic or aluminum) should not be in walls due to fire hazard. Also runs should not exceed 8' with turns counting as 2' each. Lastly if this is an outside wall there will be a lot of condensation in the line and your insulation i comprimised. I often build a short wall inside the drywall of the outside wall that is as tall as the back of the washer dryer. Then you can run the mechanicals any way you want, and there is a little shelf for the. dryer sheets and single socks.
Tom & Mr. T,
Thanks for such a quick response! I wish I could go back and tell the other sub to fix what he messed up, but in this case I'm glad it was me who fixed it since this was a serious structural problem--I wouldn't want that stupid HVAC guy even trying! And as for specifying certain materials or installations, I can't; I'm the bottom guy on the framing crew for a contractor who has four superintendents, each with his own set of subs. The best I can hope for is to talk to my super and suggest things be done differently next time. I also wondered about problems resulting from having a pipe with warm air flowing through it running up a cold exterior wall. That condensation will evenually corrode the cheap pipe and cause moisture damage in the wall. Let's just say this won't happen in my house.
this only reinforces my belief that Plumbers and HVAC subs should not be allowed to have a saw in their toolbox.
Had a similar situation recently with a sub installing Air Con pipes....cut through most of a structural top plate. I called the engineer in and he got us to plate it both sides with 1x1 angle iron screwed to the plate. The sub was backcharged for the damage and the engineers costs. He may have learnt his lesson. Our code allows a max hole/notch of 3/4" and must be kept in the middle third of the member.
Not sure where you are, but check the codes in your area for permissible notches, and cut outs, etc. Your post sent up a red flag in my brain, and I'm not sure you'll be out of the woods when inspection time comes around.
If there is no inspection, then it's up to you....
Jake Gulick
[email protected]
CarriageHouse Design
Black Rock, CT
Thanks again to all for the responses. Let me respond to all the comments made thus far that I can remember: 1) I believe this house was inspected after the fact, so the inspector should have seen it; otherwise we wouldn't have been at the house for the callbacks. Plus it already has the roof on it, and a house is normally shingled only after inspection in my area. 2) As far as a 2x6 wall in concerned, we only use those where we have a 4" PVC drain pipe (I think it's 4", not sure though). This particular wall was the front exterior wall, so 2x4 construction is the norm. 3) Regarding calling an engineer, checking codes, etc., that is out of my responsibility. Not that I like this situation (obviously I don't), but because it would not look good for a carpenter's helper to be asking about this behind my boss's (and his supervisor's) back. I can also say that mistakes like this go uncorrected all the time, and some of our inspectors are more ignorant/ stupid than the worst subs. And 4) I stated in my original post I nailed a metal strap across each of the top plates. Looking in my Simpson Strong Tie catalog they list the same strap being used in the same application--hopefully it's not just a sample illustration! In closing, I'd just like to say that regardless of whether or not this has compromised the structural integrity of the wall, it looks very weak and unprofessional, and makes me wonder if this is what I have to look forward to in the years to come and when start my own crew.
Quality Before Quantity
I have to disagree with most of the comments that you have received. Of course it is possible that this plate has a structural component that is necessary, but most plates do not need to be continuous once the entire structure is up. It is very rare to have a pipe chase in residential construction. Usually we are given a 2x6 wall to run our plumbing vents through. If you drill a perfect 4" hole you will have 3/4" on both sides. That little bit of wood will do little that the sheathing isn't doing. The plate will be stabilized laterally by its connections to the joists or rafters. You do need to look at each case individually but that is my point. It is good to see that you are conscientious and concerned about the quality of your frames. Keep up the good work.
Careful,
You just suggested that something might NOT be a structural issue.
That's not allowed here.
This guy clearly needs to consult an engineer before proceeding any farther.
;-)
Edited 1/4/2003 5:31:45 PM ET by NannyGee
Oh No! the E word!
Run for cover!.
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
I am not suggesting. I am saying that it is very unusual for the plates to be a structural component other than as vertical component of the wall. In other words you need to have a solid plate above the studs and under the joists or rafters, but you could probably cut it in every bay without causing a serious structural problem. I am not suggesting that anyone do this but it is similar to the situation in a balloon framed building.
It is possible that the plates have a structural need to be continuous and uncut. If you frame a gable wall with a cathedral ceiling in two sections you will need a solid set of plates, at the least. I have used such plates before and they certainly are necessary when you are framing the structure. The framer has to use his head and should have an understanding of the basic stresses on the structure. If you don't understand these stresses you should seek the help of an engineer. However if the engineer suggested putting angle iron on both sides of the framing around the vent cut and this was just a normal set of plates, I would call this overkill.
With respect, I've read some bad advice on this forum, but this comment tops most.
I am not suggesting. I am saying that it is very unusual for the plates to be a structural component other than as vertical component of the wall. In other words you need to have a solid plate above the studs and under the joists or rafters, but you could probably cut it in every bay without causing a serious structural problem. I am not suggesting that anyone do this but it is similar to the situation in a balloon framed building.
Please pray tell, how this is a similar situation to ballon framing?
The framer has to use his head and should have an understanding of the basic stresses on the structure. If you don't understand these stresses you should seek the help of an engineer. However if the engineer suggested putting angle iron on both sides of the framing around the vent cut and this was just a normal set of plates, I would call this overkill.
I would suggest by your comments that you do not understand the stresses placed on a building. Are you presuming that every building is sheathed for a start?
regards
mark
Quittintime
"Please pray tell, how this is a similar situation to ballon framing?
I would suggest by your comments that you do not understand the stresses placed on a building. Are you presuming that every building is sheathed for a start?"
The situation is similar in that there is no continous plate in a balloon framed building. Of course you would have to be a lunatic to cut the plate in every bay. Cutting it in one bay should be perfectly ok if, as the original poster said, the building is sheathed with structural sheathing. I am also presuming that there is a floor or a roof immediately above the plate. If that is the case, what are the stresses that require a continuous plate?
> The situation is similar in that there is no continous plate in a balloon framed building.
I've never seen a balloon frame in person. Did they really put the ceiling joists and rafters on top of the studs with no horizontal member in the plane of the wall? I've heard that the floors were supported by ledgers nailed to the sides of the studs, sort of like decks are added on to buildings now. Wouldn't they have done something like that for the roof and ceiling? In any case, balloon framing is no longer allowed. Isn't balloon framing a weaker design than modern platform framing?
> I am also presuming that there is a floor or a roof immediately above the plate. If that is the case, what are the stresses that require a continuous plate?
The first thing that comes to mind here is seismic loading. IIRC, code requires butted ends in upper top plates to be at least 4 ft away from butted ends in the lower top plate.
-- J.S.
In balloon framing the floor joists are nailed to the side of the studs. They should be supported by a ledger that is let into the studs. Balloon framing is not illegal or contrary to code but does require a lot of additional fire blocking. It is also difficult to frame because of the height of the walls. It is rarely used now.
Is it possible to use a single top plate if the framing is stacked directly over the studs? We always use a double top plate but I have read of wood conserving techniques that use I single top plate. I have no idea if this meets any code.