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You can drill a hole for a 3" waste pipe in a joist just so it's pretty near the center of the joist vertically and not in the middle of the joist span. Let me know if you want that clarified.
Are you saying that the opening should not be dead center in the middle but closer to the????? (don't know what it's called) as long as it's equal distance from top to bottom? I'm not sure that made sense.
Let me try again: a hole can be drilled in a joist just so that it is not near the center of the length of the board, and just so that it is not closer than 2" to any edge of the board. Those are the basics. Your mileage may vary. Really though, you need to contact your local building inspection department to get the exact requirements for your area.I did a web search: http://www.co.fairfax.va.us/gov/dpwes/publications/basements.htm
Look at the picture about 3/4 of the way down the page. Matt
There was a lengthy discussion not too long ago about drilling and notching joists. Holes can be drilled anywhere along the length of the joist and the dimensional limitations are just as what you said.
Tom:
Not sure I understand your statement: "Holes can be drilled anywhere along the length of the joist "
I've only lived in 2 states but I thought not drilling/notching in the center of the length was a pretty universal thing. I could be wrong. Maybe it's different where you live.
OK, so, I went and looked it up. This is just the code we use here in NC. The title of the picture is "Acceptable Location of 3 5/8" Diameter Hole in Joist":
http://www.amlegal.com/nxt/gateway.dll/NC%20Residential%20Code/part00382/chapter00657/section%20head00661/section00680/subsection00682.htm?f=templates$fn=main-nf.htm$3.0#JD_FigureR502.8
The text says 1/3 of the joist depth (my hard copy) but the picture shows soemthing a little different; it shows a 3 5/8" hole - what is necessary for a 3" PVC waste pipe - I think the insinuation is that you can exceed 1/3 the depth with reinforcement that is installed before the big holes are drilled.
This link shows 3" waste pipes going through joists that are reinforced with OSB. http://www.co.henrico.va.us/bldg/pdf/WrapUpModule.pdf The pic is about 1/3 of the way down the document. The document is on VA code, and I think anyone here who lives in VA should read through the whole thing - assuming they are interested in building ;^)
Really though, the Boss is right as far as it not being the best idea in the world, especially if it is going to be a ceramic tile floor - which will premit no flex. I guess remodelers run into this kind of stuff all the time. Matt
In our area max. hole in a 2 x 10 is 2-1/2" edge of hole must also be 2" from edge of joist
Most waste lines are 4", not 3". And you can't get a 4" pipe in a 4" hole - It would probably have to be oversixed a hair to actually get the pipe through. And plumbers are not known for being delicate with framing materials.
IMHO, this is a bad idea. I wouldn't go for it.
I don't lie, cheat or steal unnecessarily.
Boss:
Around here all toilets get a 3" PVC waste pipe. If you have have 4 toilets in the house then the main pipe exiting the house is a 4". Otherwise it is a 3". Easy to remember: 3 toilets: 3" pipe. 4 toilets: 4" pipe.
Thoses sizes are ID. So, the OD is around 1/2" more.
Matt
3" pipe is 3 1/2" OD and 4" pipe is 4.5" OD. So your hole sizes will need to be a bit greater than that. And most ABS toilet drain piping I've seen is 4" not 3". So if you've got a 2x10, you'll be able to squeak a piece of 4" pipe through if you carefully centre it in the joists from top to bottom. The trouble if it's a long run is that you'll need to slope the pipe to make sure it drains completely, and that will force you away from dead centre in the joists at either end.
In NC, we don't use ABS for waste pipes in new construction. I've read there that they use the black stuff in CA. Is that where you are? Just another thing that is done differently in different parts of the country I guess.Matt
I'm in Canada and we still use lots of black ABS pipe up here for drain/waste applications. Noisy, but pretty easy to work with and lasts a long time. Contrary to my previous post, both 3" and 4" are used for toilets.
I agree with the others- I'd avoid running across the joists too if there were another acceptable way around it. If you're running across several joists, and holes are permitted but notches aren't, then how do you get the pipe in place without putting in a whole lot of couplings? Too much temptation to notch instead of drilling holes (not good!), and too many potential leakage points for later if you go the couplings route- so it's a bit of a lose-lose situation.
But if you need to, and the others' interpretations of the applicable local codes are correct (I have no way to know that), you might be able to get away with drilling the holes and putting in the couplings-and that's what the original poster had asked, I think.
Just curious about using ABS waste pipe and how it compars to PVC. Ease of installation/price/durability? Anyone?
What happened to the reply button in 37191.10?
Matt, 35993 is the thread I mentioned about drilling and notching joists.
Just like Moltenmetal, I live in Canada and ABS seems to be the standard here. I wonder if PVC burns like ABS, terrifying.
Partial burning of anything is bad news- you get toxic products unless you burn hot and with lots of oxygen. PVC doesn't really burn if you light it- it pyrolyzes and produces toxic products like hydrochloric acid and dioxin in an oily, acrid black smoke. ABS burns quite a bit more energetically, and it too produces toxic emissions of stuff like styrene. When the pipe's burning, the joists and flooring and everything else is burning too- and we use lots of materials in our homes that produce bad stuff when they're burned. I have the greatest respect for firefighters- they're taking their lives in their hands in facing the horrible toxic soup that's produced when a modern home burns. But then again, so is anyone who smokes cigarettes, or lives with a cigarette smoker...
As far as ease of use is concerned, both ABS and PVC are as easy as it gets. Both use solvent cleaner and solvent cement systems which are pretty easy to use. One word of advice, though- don't skip the cleaner step, because you need to use the cleaner to soften the plastic to give the glue a good bonding surface. I've seen more than enough PVC joints pop under pressure when the installer skipped the cleaner step and just slathered on the glue.
Up here, ABS is way cheaper and more readily available for DWV applications than is PVC, though you can get both.
Thanks for the ABS/PVC "primer".
Matt
PVC, Polyvinyl chloride. When burned, the chloride is released. Same or similar stuff they used in the trenches in WWI, i believe, chloine gas. Firefighters were overcome by the stuff early on til they figured out what was going on. Nasty stuff.
As part of an emergency response crew in the USN for a radiological controls division that used copious amounts of the stuff, we were told not to enter a burning building (even with an OBA on) if PCV was burning. Of course, that was in the 70s. Things might have changed since.
I never met a tool I didn't like!
PVC doesn't produce much chlorine gas when you burn it. It makes hydrochloric acid vapour- just as bad, if not worse, when you breathe it in. It also makes dioxin- one of the nastiest substances known to man. Dioxin messes with your DNA...
There was a fire at a recycling plant that processed PVC in Hamilton, Ontario. Now we've got a lot of sick firefighters...
I'm still living in a house that was built in 1959, and new when we moved in. After several months we noticed cracks in the plaster, and he carpenters who built the house were shocked to find that the plumber had completely severed a triple joist. A couple of steel jack-posts were put in and no more trouble. Keep an eye on those plumbers!
Tom
"carpenters who built the house were shocked to find that the plumber had completely severed a triple joist. A couple of steel jack-posts were put in and no more trouble. Keep an eye on those plumbers!"
Yeah, they often have to deal with framing where no thought has been given to mechanical considerations. Not that I condone severing a triple joist, but I see lots of situations where the foreman and the plumber never talked about drain locations during framing. If you bother to ask the plumber s/he'll usually make it clear what they need for pipe clearance.
They both burn. I,ve worked in fire/earthquake prone areas that require cast iron becouse of it.
My firefighting instructor used to refer to the smoke from any modern structure fire as 'methyl-ethyl-badsh!t'. I think that about tapes it....
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
I agree with you. There is no way I'd go crosswise to the floor joists unless there is support nearby at either side of the holes. At least two more problems I see with this. One, elbows take up space. There's no way that a 3" elbow (nevermind a 4") will make a bend such that the horizontal run would be near the center of a 2x10. Second, how would one feed a length of 3" pipe through the line of holes without putting a coupling between every joist?
Couple of different Ideas, what's the lower level ceiling height? if high enough you could run under and fir the ceiling down or box out a small area. Or you could maybe run above the joist and make a platform design if room permits. Funny How little always grow to be umph. If worst comes to be you can limit the # of joist to be crossed and reinforce those to meet the code. There goes the Ceiling below.
Clay
Coming into this discussion a little late, but I want to say that I'd avoid going through the floor framing with a drain if at all possible. It's difficult to do cleanly, and it definitely compromises the strength of the floor. It depends a lot on the overall structure--I'd sooner go through one or two old joists that are full-dimension 2x10 spanning 7 feet than I would several new 2x8 joists spanning say 11 feet. Are you going to install tile on that floor after the pipe is in? If at all possible, get the pipe down under the floor, or find a way to run parallel to the framing to a new drop. Or hell, run it exposed on the dining room ceiling! Just kidding, and Happy Thanksgiving!
if its on the bottom floor over a crawl space can't you drop below the joist?
The best employee you can have but you wouldn't want him as a neighbor " He the shifty type"
Thanks everyone, for all the replies. The contractor that gave me the bid intended to move the toilet and run the waste through the joists. It didn't sound right to me so that is why I posted here, knowing I would get the answers I need. It seems as if it is possible to do but is not looked well upon. The issue of having to slant the pipe also seems complicated and tricky. I have decided not to allow the joists to be cut since ceramic tile is the flooring of choice. This house has enough uneven floors, anyway and long after the contractor is gone and the floor cracks, then what? The toilet will have to stay where it is unless they can creatively box in the waste pipe in the hallway ceiling below to allow the pipe to run below the joists. This is a possibility since the plan calls for demolition of that area anyway.
Now if there are any kitchen and bath contractors out there, could you please check out my next string of what info I can get to make final decisions?
Happy Thanksgiving!
I would avoid it unless I had a good way to sister in reinforcement and know that it would do the job..
Excellence is its own reward!
If notching the joist or boring the joist are the only option, couldn't you sister a piece of 1/4" steel to both sides of the joist to compensate? I'm faced with this similar problem and was thinking that this may be a viable solution. Of course I don't know any load tables for the steel but am curious to find out.
IU can imagine patching one in similar manner occasionally when I have to, supposing a plumber screws up and ignores my or I come along after the DIY started the job and i need to fix the basket case.
But I would never make a plan to do it that way. If a homeowner insists on moving a fixture to a place it cannot go normally, that means they have to pay to reframe the space to accomadate their desires..
Excellence is its own reward!
This is from DIRISHINME in an earlier post, showing proper ways of reinforcing the messed up joist.
>This link shows 3" waste pipes going through joists that are reinforced with OSB. http://www.co.henrico.va.us/bldg/pdf/WrapUpModule.pdf The pic is about 1/3 of the way down the document.
One thing they didn't say was how messed up is messed up, I don't think you can repair a joist cut in halves with what they provided.
The problem with something like this that steps outside the standards is that there is no clear stopping point once you begin and hack work follows.
IOW, I might slide a patch inhere and there, based on my judgement for the situation at hand, but if we start advising how to chop shortcuts together to amke something work, we have already thrown out the standard and have nothing to go by anymore. Suppose that normal work gives a (imagine) score of 100 and the sister repair gives a 90 when a 92 is needed. Close enough? sure, if done well, with all precautions and an extra nail and squirt of glue here and there.
But then some body reads in "fine Homebuilding's forum" that it is OK to do this or that or something else a little bit below the standard and then they cobble somethig together that for lack of experience and judgement only scores 72 in quality, ebven though they think they doid it the same way as recommended.
Tjhere is another point that concerns me in this thread, and I don't know what I thionk yet so I'll just lay it out for others to comment on. That is the fact that this contractor said he woulod do so and so withoiut eleboration.
I might make a similar statement with some of my customers and they don't want to know the details of how I'll get from point A to point B - only that it will look good and function well when I'm done.
But there are hacks out there who will hide their methods behind such a statement, so it is good for this gal to get educated.
I know some architects are good at waving their hands around and painting a vision with a broad brush - then they come to me and tell me to do the impossible without regard for cost when a simpler solution is at hand, like reversing the door swing as she memntioned.
LOL.
Excellence is its own reward!
One of my first thoughts after reading the original post was it all sounded more than familiar, was it really worth it to go through so much just to reverse the two fixtures? May be a half wall or as she suggested just reverse the swing of the door would result in a workable solution. To me it's value that counts. Cutting all these holes may not compromise the structure but I am sure that would create enough flex to compromise the tile installation. I just don't have a good feeling on this.
Tjhere is another point that concerns me in this thread, and I don't know what I thionk yet so I'll just lay it out for others to comment on. That is the fact that this contractor said he woulod do so and so withoiut eleboration.
Now I had some time to think about your concern here is my comment.
If as you said some of my customers and they don't want to know the details of how I'll get from point A to point B - only that it will look good and function well when I'm done.
All would be well if everything holds up but if they are hacks out there who will hide their methods behind such a statement and if things start falling apart, and if the whole matter ended up in the court of law, then it becomes issues of disclosure and consent. It boils down to if the hack is negligent in that he did or didn't disclose enough for the customer to make an informed consent for him to go ahead with the job. Then his work will be held to the standard of practice in the profession.
Inform before you perform is paramount in even what you think is a simple situation, just can't take things for granted.
I can see your point but not agree in all circumstances.
For instance, we have had several go-'rounds here on one subject or another, weighing pros and cons. First to mind is the ceiling issue; I can use 5/8" sr with framing at 24"oc or 1/2" SR with framing @ 16" oc or frame @ 24" with strapping @16" to use the 1/2"
I really don't think most owners give a hoot as long as the ceiling stays flat and the cost is competitive and reasonable.
Going into all the detail of pros and cons on something like that will confuse them and leave them with the impression that I want them to decide because I lack enough confidence myself to make that decision.
But I do bring them other more critical decisions. As a design/builder, I am hired in part for my experience, judegement, proficiency, and ability to amke reasonable decisions on their behalf..
Excellence is its own reward!
Inform before you perform is paramount in even what you think is a simple situation, just can't take things for granted.
O.K. may be I misled you or shouldn't have put in "a simple situation". I agree with what you said in your post. As in your SR example, I would not ask the customers if they want their kitchen cabinets installed with 1 1/2" or 2 1/2" dry wall screws. :) We all have our standards of doing things and we know we are comfortable with those standards and they work well for us. I don't want to get consented to death otherwise when do we find time to do the work. I don't know anybody here charge their customers for talking to them although it may be all factored into the contract. My lawyer charges me $50 for every phone call which lasts 15 minutes or less.
Back to this waste pipe case as an example. If in the first place I don't feel comfortable cutting into the joists, I wouldn't even mention that as an alternative and I would present other viable solutions that I feel comfortable with. If they say a plumber told them that he would cut through the joist to get the job done then I'll explain to them why I don't feel comfortable doing so and if they want to go ahead I don't want to have anything to do with it. That's the kind of decision making I would get them involved in instead of them coming to BT asking about cutting holes in the joist.
Hope I make myself clear. :)
As a design/builder, I am hired in part for my experience, judegement, proficiency, and ability to amke reasonable decisions on their behalf.
And for your excellent typing and proof-reading, no doubt...
Piffin is always Piffin, leave him alone.
OK, OK, personal foul... I should have just asked him how his progress is coming on the policy statement he is writing for his insurance guy...
He writes policy statement for his insurance guy?
O my Gawd. :)
You mean he wuz picking on me? I thunk it was just a love nudge.
;)
Iam going to bee very carefull to tipe this write because Iam threw entertaining people with my tyepole errors. No moor will I make any misteaks when I write. From now on, they'll have to just pretend that I am imperfact. Iam threw proving it.
;-).
Excellence is its own reward!
Slow down Piffin, you're trying too hard. Keep up the good work. :)
It's been a while since I've practiced as a civil engineer (probably an invitation for at least a couple of salvos) but with that said I don't see why sistering additional framing or bolting a steel plate on hasn't really been discussed here. I never practiced alongside homebuilding and I'm not familiar with local building codes (was employed in nuclear power plant industry, well what once was an industry) but I'm sure they must be considered a viable alternative to hacking a hole and leaving it or saying it can't be done.
The original joist's capacity is related to the type of timber it is and the moment of inertia of the cross-section of the joist. The bending stress in the joist is Mc/I where M is the moment, c is the distance from center (of a rectangular cross section) and I is the moment of inertia. I is also used to compute deflection. You can also consider shear (P/A) at that point but that probably isn't the controlling stress.
The loss of wood reduces the moment of inertia of the cross-section at the point it's made, thus increasing bending stress, shearing stress and deflection. The moment of inertia is least effected by holes drilled from the center of the member, hence the code requirements for notches and holels. If additional wood were used to sister alongside the hole, restoring the moment of inertia to a value equal to that prior to the hole then this ought to be sufficient. I'm sure there must be some local building code requirements for the length of the required timber sister and its connection or the manner in which a steel plate is connected in order to properly transfer the load through the compromised joist.
Those are good points but it really has been mentioned in this thread before, in a couple of ways. One person refered to using angle iron fasteneed to the bottms to reinforce, and a couple of others mentioned hiring an engineer to tackle the task.
The reason something like this is not covered in the code books is that the veriety of choices and situations is almost infinite. code books weigh enough to serve as door stops on windy days as it is. You would need a wheel barrow to carry one that covered all the eventualities. Instead, it says that you need to design for _x_ live load in _Y_ locations. The lumber span charts show us what works to satisfy that in normal circumstances, but when we step off the chart, we need engineers to calculate what is happenning in a unique load carrying member.
Had this thread been introduced as a "What do I do now that my plumber has ruined my floor joist" I may have given more detailed advice how to proceed to fix what was already screwed up. But to advise anything other than to refer to the PDF I posted above or to consult an engineer is to encourage substandard work, IMO.
To compare to your industry, You guys probably sat around at coffee break talking about other ways to do whatever it is that your systems did in those nuke plants. And in an emergency, you probably could have concocted something jury rigged that might function or save lives.
But you probably wouldn't go around recommending it as a good way to proceed in normal circumstances.
Although, I would also imagine that in nuke plants, there is a proceedure book laying around to consult in emergencies, and you hoped that every contingency was covered. Of course, that redundancy and the drills probably added to the cost of nuclear energy..
Excellence is its own reward!
Just in case you come across this in the field and someone suggests "ah, can't hurt that much putting it at the end if they allow it in the middle" you might convince them otherwise with the following.
The moment of inertia, I, for a rectangular cross section is (w)(h*h*h)/12 where w is width of cross section and h is height. If you reduced the cross-section by 1/3, i.e. the height h, by notching at one of the ends then the new I (all else being the same) is ((2/3)h)^3 which is 8/27 = 0.296 or less than 30% of it's original bending capacity. Reduce by 1/2 and it's 1/8 of original bending capacity. Ouch!
However, if you penetrate the joist with a hole equivalent to 1/3 its height so that it is centered at the exact mid-section of the joist then the moment of inertia is not nearly so adversely affected. The number is very surprising for that type of hole. I won't say exactly how much since it might be too tempting an invitation for a slew of holes.
yes.. and if it's gotta be , it's gotta be...
most of our waste is 3" max.. (3.5 od)
which leaves 3" above & 3" below the pipe.. if the cleanly drilled holes ( cut with hole saw ) start at 2" from the top, they can end at 2 " from the bottom.. giving up to 2" pitch across the room..
i'd glue lam 3/4 ply to each side of the joists to be hole sawed and let my plumber have at it.. and yes , he'd use a lot of couplings.. ..
i bet my glue lammed double 3/4 ply & joist sandwich with a 3.5" hole in them are stronger than the original untouched joist..
if in doubt, i'd call up my PE and have him run the numbers..
Mike Smith Rhode Island : Design / Build / Repair / Restore
if i had to do it and had no other choice i'd run the drain in 3" copper keeping the holes as close as i could to the end of the joist... you'd have no way to feed the pipe in other than in 14.5 lengths and i'd have to braze or silver solder each joint... but the OD hole wouldn't eat up ur joist... the $ factor might be high but still cheaper than most options.... btw i ran into a water closet plumbed into a 2" drain line once (pvc so it couldn't THAT old) i asked about it and was told it was in constant use and had never caused a problem... no tell'n who'd done it but i guess they got away with it
pony
Have you verified the direction of the existing joists? Maybe you're one of those rare guys who gets lucky.
It may well be too much work to be justified, but if moving the toilet is very important to your design, maybe you could put in a pair of beams to carry the load of the joists and create a channel for the drain. The floor will be open, so you'll have good access to the framing.
As suggested above, it may be possible to run a new drain down behind the new toilet location. This may not be a difficult as it may seem at first, especially if you are gutting the bathroom and have access to the area below the first floor. Maybe the old drain could serve the new sink and tub location so you don't have to drill any joists.
Al Mollitor, Sharon MA
The project hasn't started yet so the floor is still in tact. I did think I might luck out but judging by the way the floor is uneven now, I have a feeling about the way the joists are running. A plumber I called in from the outside looked at the job and said the only way he would do it is run another waste pipe. There is a wall available to do that and he would include the first floor dishwasher and kitchen sink because of proximity. His cost was 3000.00 which really doesn't matter because I just want it done correctly. The remodeling contractor suggested moving the toilet so it was behind the door when opened. I'm thinking of just changing the way the door opens. :)
Ditto Mike Smith's post- after 26 yrs. in the remod biz this approach has never failed. But be reasonable; don't bore a 3.5" hole out of a 2x6 for instance and expect it to hold up. If in doubt consult a PE.
More than often on TOJ when they have demoed an existing older home they have found that this was done over the years by plumbes.Some, the joists have little if any thinkness left.
The bottom line was that if caused structural problems depending on how much load that joist was carrying. Perhaps you could box through your joists to create a space for the waste pipe if you must move the toilet.
Not understanding clearly though, why not put the sink where you're going to move the toilet and leave the toilet where it is? It would save costs by adjusting the design to accomodate the structure
Thanks for your reply. It sounds as if sometimes you can get away with cutting through the joists and sometimes not. Just as you mentioned, it depends on what load the joist is carrying.
I don't think it is worth the effort to find out if this would effect the structure nor would I know how. I certainly don't want to do it if after the room is gutted and try to figure out from there. I think it would be much better to know beforehand.
Moving the toilet was how the contractor designed the remodel - so that the toilet was behind the door when opened and the vanity was nearer to the natural light of the window. As you suggested, the toilet will be left where it is and the way the door opens will be changed. To go through all that would be required to do otherwise seems such a waste. I would rather put money into nicer fixtures instead.
I agree with everybody who has expressed reluctance to bore the floor joists for a pipe this size. It's not a good idea. Plus it's a PITA. The contractor who stated he'd run a new drain line sounds like the one who's on the ball with this.
There are several ways to do this, none of which should be a major problem considering you're planning on gutting the existing bathroom.
One of the easiest is to frame a pipe chase down the surface of the wall below the remod, gyprock it over, and once you get the waste pipe into the basement you should be able to run it any direction you need to. A nicely finished chase running ceiling to floor on the surface of a partition wall can usually be worked into the room it's in without too much trouble. Hard for me to be sure without seeing your FPs, though. Just an idea....
If that won't work out to your satisfaction, bite the bullet and rip open the downstairs wall and run the new drain. Once it's done, it's over with and you can move on to more fun decisions, like what kind of mosaic you want on the floor....
Stuff like this, taking the decision is harder than the actual work....
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
> One of the easiest is to frame a pipe chase down the surface of the wall below ....
Yes, but this is one of those situations where we can't possibly know enough about the specific situation to say such a thing for sure. For instance, we may find that the soil stack would have to drop right down thru the middle of a window downstairs. We can discuss at great length things that often are the right way to go, but what is right or best for this specific house can only be determined by being there.
-- J.S.
You're absolutely right. No way for us to know unless we can see the house or a good set of plans of it. I was just making a general comment, offering it as one possible solution for consideration.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Glad to hear you wont be drilling threw the jiosts.I see you would like all the options so here are a couple not yet mentioned A plumbing ladder : that is to remove a floor jiost (or two if on 12inch centers ) and install flat blocks every 12inches with nails and glue..another option to consider is to double up a selected jiost and then run your joists in the more convinent direction from the double with hangers ... either method is inexpensive and shouldnt add anymore than four hours work to your payroll
A Canadian Carpenter
Thank you for the reply. Both these options sound acceptable to me and I am printing them to show to the potential contractors. The replacing of the support lost is what concerned me. I know enouigh just by the hack jobs done in my basement running furnace ducts that removing sections of a joist just isn't right.