Engineer specifies a 18″ footer width. Plans drawn as such. Builder says he wants 24″. Engineer says he doesn’t care, as long as they are at least 18″. Should plans be redrawn for 24″?
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<<Engineer specifies a 18" footer width. Plans drawn as such. Builder says he wants 24". Engineer says he doesn't care, as long as they are at least 18". Should plans be redrawn for 24"?>>
Not long ago this question would've evoked smiles and laughs on all sides. Nowadays, sad to say, t'ain't nothin' funny about it.
The usual rule of thumb is..."meets or exceeds"...so I wouldn't mention the change to anyone. IMO, it's not likely to be noticed and, if it is, there can be no serious complaint about it.
I am not an engineer but as a point of CYA your left to adjust to the needs of the bigger footer. This might throw the liability your way.
Let's say for sake of argument the 18" footer is actually inadequate, all issues come back on the engineer or architect. But you adjusting to the builders demands without upgraded spec's put all issues on you.
If the engineer doesn't care fine but the builder should pay for the engineers rework. Cost of his desire to be Code Plus as it were.
Just my thoughts because I've been there in the middle between builder and architect. I don't care what they want happy to oblige but I don't want to be fall guy.
To clarify, I'll draw whatever the engineer specifies. My position is that we can't be changing drawings each time a builder states a different preference to the HO. If the builder want to do something else, that's their prerogative, but that doesn't mean a new drawing necessarily.Here's an example. Engineer specified an 18" footer. I drew that to match. Builder tells HO that the county won't approve an 18" footer for anything. I call county and they say of course they'll approve whatever is specified on sealed engineering. He says that sometimes guys will go with a 24" footer because that's the size of the bucket digging the trench. So, do we redraw 18" as 24" for builder convenience at cost to client, or stick with the 18" specified on the drawings and if he goes wider, that's his choice? I like to accommodate builders, but...
Edited 5/3/2007 11:44 am ET by CloudHidden
Anytime things are CodePlus or greater than engineered I think it's great. Only considerations usually are is the improvement expense justified to the benefit of the increase.
In this case as you've said the fact that it may be due to simply bucket size or forming materials makes since if the cost of a new bucket, machine or additional forms actually increases construction cost.
Example for me:
I have a typical cabinet shop set up and when a designer spec's a simple set of cabinets I try to accommodate. But sometimes my setup is faster and the savings they are trying for is met by that set up. I don't tell them why there getting a set of better than spec'd cabinets even though my cost usually work out about the same. They just think they got a great deal. For the most part time is my only demon.
And who is going to pay for your time to redraw it? This sounds like something that the builder should note on the as-built drawings (if you require them) with a nice cross-reference to the engineer's approval.
as a builder there is no way in h3ll I would pay to exceed an engineers design minimum.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Get the statement from the engineer in writing and signed by the P.E. that 18" is min.
As an engineer, I put a note on my drawings stating that I am to be notified prior to making any changes to the plans, specifically structure..
Typically, I would issue a letter indicating the change. If there are a lot of changes, then I may re-issue the plan..
My question is why is the footing being increased? Is the builder planning on using a wider footing to support something else, like a brick or stone veneer or something else that might not have been in the original plan/calculations?
"My question is why is the footing being increased? "That ran thru my mind.
The options that I came up with are ease of layout and placement - The original laout does not have to be as precise with a wider and the walls can be laid out better once the footer is in.
He might be used to using spreaders that are 24" and that is what he has.
Maybe he does trench footings instead of forming and the bucket on his hoe is 24" wideOr maybe he has done a lot of foundation work and has seen failures in 18" wide and has an instinctive disregard for the narrower footer.BUt if there is a change to add a brick facade like you speculate, then the whole thing needs redrawn and re-engineered, true. Since Jim does domes, I tend to doubt that though.now that I think about the dome factor, I lean towards the layout and trench footer consideration on this as a reason.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
This one's interesting be/c it's an ICF wall with a domed roof. Really neat hybrid with a huge potential--disaster resistance of the other stuff I do with the public acceptability of ICF and vertical walls. We drew plans. Every time HO spoke to a new builder, came back with different requests. We've been chasing our tails to accommodate builder preferences and it's costing $$$. Finally got suspicious when I heard from builder through HO that 18" footers were not permitted by county and that the ICF's could not be modified as we needed for one detail. Assuming the comments were passed on accurately (which is not a given, in a "Whisper down the alley" sense), they didn't ring true. So I called the inspector and the ICF manuf and each had no issue with our original plan.Hmmmm. That means the builder either said something that was not true, or was not quoted accurately, or just wanted a change for personal reasons (convenience, his economy, etc). I'm uninclined to draw new details for any of those reasons. Engineer and I just spoke and are gonna stick with original layout/dimensions, and builder can vary from those as he determines appropriate, but that's on him, and what we're documenting is what we recommend.I'd hate to not seem cooperative with the builder, but there need to be limits to modifying plans....yes? no?
Yes. I would do exactly as you are doing this.
As a builder though, I often exceed drawn specifics from other designers, alwyas with a phone call first and a written note to document but never a problem from the designer.On the AHJ issue others have mentioned, I don't conceive of why....in spite of my high IQ
;)
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
He is pouring it neat, using a 24" hoe bucket to trench. That's what it's about. Apparently the excavator doesn't have an 18-incher.
Seems like a no brainer to me, but here we've gone over 20 posts worth of discussion. Cloud Hidden didn't mention the bucket deal upfront, however. If he had, this would have been a shorter thread.
>Cloud Hidden didn't mention the bucket deal upfront, however. If he had, this would have been a shorter thread.You've got one helluva bedside manner. It came up first in a conversation with the inspector 2 minutes before I mentioned it here. The situation evolved in real time as the thread evolved.The point is that we don't know why the builder wants what they want. We're just guessing. We only know what he says as passed on through the HO. Don't know who the builder is. No contract between them yet AFAIK. That one reason I'm not inclined to make changes. We'll design what we think is right. Engineer and I are on the same page as the inspector and the product manufs. As for builder-inspired changes, my name's on the prints if he wants to contact me. I've put a stop to the HO-as-middleman stuff.
Cloud,
From a practical point of view, when working with ICF's wider is a lot better. Your builder might be one of the many who like to place cleats on the footing to keep the ICF in line. If the 18" footing is as little as 1 1/2' off perfect placement then you have next door to nothing left to fasten a cleat to.
Your bracing foot sits down there, too and needs about 2 1/2" to rest on.
What's 1 1/2" in a footing alignment? Not very much of an error and easy to do especially if the plan is tricky to lay out. Stakes don't drive straight, rocks are in just the wrong places. Poop happens but you can avoid having it happen on your own head with a little foresight.
Also, this will almost certaily be formed rather than poured into a trench because vertical control is very important to easy ICF installation.
I'm guessing it has nothing to do with buckets and everything to do with what the builder knows about working with ICF's.
Ron
>Your builder might be one of the many who like to place cleats on the footing to keep the ICF in line.They're using a brand that includes a metal channel for horizontal alignment at the top and bottom, so they shouldn't need additional cleats.>I'm guessing it has nothing to do with buckets and everything to do with what the builder knows about working with ICF's.I'm open to this. If a builder has preferences, I'm happy to try to accommodate. Except the reason passed on to me and the engineer was that the county would not allow 18". That didn't sound right, and turns out to not be right. That makes me more suspicious of other stuff I've been told, which then hasn't checked out. Client's sold on him so that's fine with me. I'm just gonna independently check anything I'm told.
I don't see why plans would have to be redrawn for an element to exceed design as long as that element does not affect other elements of the structure. I have never yet seen a footer built to an exat size. the 18" is a minimum
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Taunton University of Knowledge FHB Campus at Breaktime.
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CYA sorry, but that's what its about letter to engineer addressing change, and does depth of footer need increase, or some rebar added, to maintain footer strength due to expanded width?? attach his letter of reply
Prolly depends on localities.
Round here it would require an "as built" final drawing.
Future renovators need to know what to expect. Running a water or gas line in the future may undermine an unexpectedly large footer not shwon on the drawings.
Wondering if you could charge the builder for the plans change?
J. D. Reynolds
Home Improvements
Should plans be redrawn for 24"?
Yes, if the AHJ insists on it. Mine would.
Or, if the rebar (if used) needs to be located differently (like if it is not specifed to be w/3 or the like; #4 bar @ 6" OC probably ought be changed).
It's probably a good idea with many footers to make sure the 3" difference does not cause any "weird" spots (like "U" shapes under 12" or so shrinking to less than 6" & the like). Also, to avoid having "all" the extra 6" going to either the inside or to the outside, or, worst yet, both. I'm thinking more of an unexpected uh-oh like remembering to "key" the footing, and centering the key way, and that not being the center of the planned wall above. Sure, it's not supposed to happen; "supposed to" has not prevented problems in real life, though.
So, "have to?"--maybe not. "Should?"--Probably.
if it doesn't affect rebar spacing, write a letter documenting the change, and have the homeowner sign off on it
explain that it's simply a procedure so he doesn't have to pay extra for changing the plans
and add a note to each affected sheet as an addendum item/revision
still a pain, kinda/sorta, but you still want to look like you're a professional (if they make changes and you don't document it, it removes you from the relationship and opens the door for more changes down the road . . . some which you might not be made privy to, but could still be held responsible for)
The only drawback I could see if the builder upsizes other stuff is how it may affect other systems in the house. For example-upsizing floor joists may alter stair layout. Is it too late in the game to meet as a group and review the plans together. I have found that kind of meeting really makes for a great set of plans. Knowing what the other guys would like to have makes everyone's job easier and limits the confusion when the plans get implemented. Coordinating framing with HVAC and plumber always makes for a better product. Just a thought...
Bruce
I can't believe the builder would ask to have them redrawn, unless he really believes that they can't be 18". 2' trench footings are the norm here, mainly based on most excavator's bucket size, but also to cover any layout errors. Ok, not any, but most errors<G>. That, and you've got to have at least a 2" projection, more if a facade.If the footings are formed, it's another story. 18" saves a bunch of bucks.Can't see why you would have re-draw, though...tell 'em that part's not to scale? Outside of the gates the trucks were unloadin',
The weather was hot, a-nearly 90 degrees.
The man standin' next to me, his head was exploding,
Well, I was prayin' the pieces wouldn't fall on me.
24" is 33% greater than 18". Is the builder going to expect 33% more pay for this? But that's not what you asked about. I would think that a notation on the as-built plans would suffice. Be sure also to note any changes in rebar...... there will be changes in rebar..... or maybe the engineer says this isn't necessary. I'd get a note from him regarding that.
That footer width change goes on the builders "as-builts.", not on your original plans.
IMO, the rebar in the footer should be placed as if it were still an 18" footer, and not 6" further apart. If the builder wants the iron 3" from the edges, he should add rebar, not respace the original.
Unless, of course, somebody is going to pay you and your engineer to redraw, reengineer, and restamp the originals.
This is real similar to substituting a 4x14 1/2 header for a called out 2x 2x12 header.SamT
Praise the Corporation, for the Corporations' highest concern is the well being of the public.
I agree with SamT on this. Unless you have some open-ended budget to provide As-Builts, which no one gets, the information should be noted as As-Built by the contractor.
On my jobs, anything that affects the As-Built state has to be okayed through a Field Change Request. This is simply a glorified RFI, but it keeps As-Built changes in one database and the engineer can do a sanity check on the impact (such as the issue with rebar #/spacing). Bucket size and steel availability affect my jobs quite often....that's not a mistake, it's rustic
As long as it's engineered (including the soil) to work with 18" wide footings and local AHJ approved the permit using 18" footings, no problem. No need to revise drawings unless the builder wants to compensate you for your time / printing costs to avoid possible future layout issues later on.
I 'd just have the builder document the changes in his as-built set of drawings. He is keeping a set of as-builts right.
Make sure he doesnt think 24" means he can skimp or skip the rebar!!!
I'd hate to see one of yer Golf balls roll out of bounds
:0)
I don't Know what I am doing
But
I am VERY good at it!!
Watch your footing thickness. In North Carolina the projection of the footing beyond the foundation walls is a minimum of 2" with a maximum projection equal to the footing thickness. In other words:
If your footings are 18" wide x 8" thick, then your footing projection could possible range as little as 2" to as much as 8" thus allowing the use of the 24" wide footing without any negative consequences. These wider footings are easier for the footing man to dig and the masons love them because they have more room to work in the ditch an well as layout the structure.
Get an addendum from the engineer accepting the requested change and forget redrawing the plans. Always get the engineer to approve all changes no matter how small they may seem otherwise build it as designed/drawn
Where do you do your inspecting? Just wondering if you've ever turned me down<G> Outside of the gates the trucks were unloadin',
The weather was hot, a-nearly 90 degrees.
The man standin' next to me, his head was exploding,
Well, I was prayin' the pieces wouldn't fall on me.
Piedmont region in North Carolina
Can you name the county? Outside of the gates the trucks were unloadin',
The weather was hot, a-nearly 90 degrees.
The man standin' next to me, his head was exploding,
Well, I was prayin' the pieces wouldn't fall on me.
Our code specifies width to depth ratio too. Lots of builders around here miss this when they increase footing width without adding height and get failed.
Right on.
You forgot, Keep on truckin'.
J. D. ReynoldsHome Improvements
Any notion what the engineering logic behind that Width to depth ratio is?
what the engineering logic behind that Width to depth ratio is?
Has to do--as a guess--with the centroid of the footing, and thus any bending or upsetting moments as a result.
A footing 36" wide and 6" thick has a longer moment arm to "fail" the concrete in tension, while also having less "space" to get bar into to add tensile strength. Changing from 36" wide to 24" wide makes a big difference if still 6" deep. Or making it 36x12"--but in a different sort of way.Occupational hazard of my occupation not being around (sorry Bubba)
Ah, so.......hope yr teeth are better....I'm getting that scare they're offering up in the Tavern ;-)
Ooops---- I meant SCAR----'course, they're usually offering up some sort of scare over there as well <G>
Our code calls for two rows of rebar in the footing, but no requirement for any ties across the width. I think the width to depth ratio is to avoid, say, a 36" wide footing that was only 6" deep. The foundation wall bearing on this is likely to shear the ends of the footing off, and the two rows of rebar won't be much help.
Edit: Sorry, I replied without reading the thread, and have basically repeated what CapnMac said.
Edited 5/8/2007 8:15 pm ET by fingersandtoes
have basically repeated what CapnMac said
Wouldn't sweat it, 'bout time somebody else was accused of telling the same thing over again (and again and again) <G>Occupational hazard of my occupation not being around (sorry Bubba)