Call from project superintendent as I'm driving... "Hey, the dimensions between grid lines B.9 and B.4 is 33ft and then B.4 to A.8 is 32ft 11 inches for total 65-11. I taped between your 3' offsets and I'm getting 60 ft. I think you busted an inch"
I had set 3ft offsets to B.9 and A.8 on the slab this past Saturday... I'm thinking that's weird, I make mistakes but it'd be strange to be exactly an inch off.
Me to super: "I'll call you in about an hour when I get back to the office. I stored the points as I set them - I'll check it out."
Two more minutes of driving, I pull over, grab the T7 controller and turn it on... compute inverse between computed grid intersection points... Azimuth 0.000, 66.000 feet. Minus 3 feet times 2 is 60 feet. For calcs, that's a CHECK...
Compute inverse between set points... Azimuth is a couple of seconds off 0.000, distance, east side of building, 59.997. Distance west side of building, 60.006.
Cool.
I pull out my cell phone where I store my layout plots in PDF format for easy access... B.9 to B.4, 33ft; B.4 to A.8, 33 ft. Good.
But now, I'm thinking "we'd he get that 32ft 11 from??"
Pull out laptop, launch CAD, yep... what I have is 33 ft. Open PDF plans... 33 ft again - CHECK.
All this investigation takes about a half hour to check, check and check again.
Call super back... "I got 33 ft... where you getting 32-11?"
Him: It's on the plans.
Me: nuh-huh... it's 33.
Him: I got the plans open right in front of me, 32-11.
Me: WTF????
I send him the screen shot of my 33ft and 33 ft grid dimensions...
Him: WTF??? I'll call you back.
Turns out....
The structural designer changed the thickness of the shear wall from 9 inches to 10 inches. This is after construction, demo, excavation, etc., already started. He decided that the face of the wall should still be on grid so simply changed that one dimension.
The other subcontractors, concrete, steel (there are structural steel elements), even the plumbers and electricians were all informed. Not me though. GRRRRR!!!!!
The 3ft offsets to B.9 remain 3ft offsets.
But my nearly perfect 3ft offsets to A.8 are now 2'-11" offsets.
Super will re-label tomorrow.
(Maxwell Smart voice) "Gotcha with the old distribute-the-plan-changes-to-everybody-except-the-surveyor trick"
Wow....That's a hot steaming pile right there.....Don't people understand we don't measure because we want to, we don't hve any choice in the matter....
Keep us posted on how the bleeding that occurred found a way to miss your buy in, or sign off....crazy!
Good to hear the super can use a tape, better than finding out with a beam.
?ÿ
I would not be surprised if this comes up again despite the appearance of you being the last to know there may still well be someone in the dark with an extra inch.?ÿ
This is why I (almost) always contact the client just before construction staking begins with the message, "I have plans dated xxx. Are these the latest plans?". At least half the time, they are not. And always when I forget to do this.
It's been a long time since I did any heavy construction layout.?ÿ I do recall one time where we started, but then they discussed changing a couple column locations, and new plans were issued.?ÿ
We went back to stake those columns.?ÿ But I didn't look at everything, and it turns out that they'd changed a couple others that we'd already staked.?ÿ Luckily the super caught that before construction, and let me know so we could go back and fix it.?ÿ
It was a good lesson to check everything when a new plan or document is sent.?ÿ Or at least request a change order stating everything that is different from the last rev, and that we're only responsible for the changes that're called out.
He decided that the face of the wall should still be on grid so simply changed that one dimension.
That's the problem right there. I couldn't care less if the wall moves, but that gridline better not once the IFC set is out.
We try (operative word there) to stake only gridlines for large structures to avoid any mixups due to plan revisions, precisely because no one thinks to inform the surveyors of revisions, and because the gridlines shouldn't be moving.
At least they called you about the discrepancy. It has become more and more common for contractors to avoid doing any sort of checks on our work, like simply pulling tape or calcing a quick grade. I try really hard to make the supers understand that if we work together to check each other periodically, the whole project will go a lot more smoothly.
I get that with the signing of Plats. Mylars sent to the City, they sign, sent to the county, they say wrong owners.
Call the client, they say, Oh we sold that off 2 weeks ago. Surveyor says......crickets!
That's the problem right there. I couldn't care less if the wall moves, but that gridline better not once the IFC set is out.
Exactly. This isn't so much of a "you should always double check that you have the current set of plans" issue, and more of a "designer needs to get smacked" issue.
Of course we should always verify that we have the latest and greatest plans- but the grid should NEVER move. You want that wall line on a grid line? Fine- add a line. NEVER move or remove gridlines. Period.
That's the problem right there. I couldn't care less if the wall moves, but that gridline better not once the IFC set is out.
Exactly. NEVER change grid line dimensions once plans are made available, even prelim plans. We get started with 90% plans all the time.
what's annoying (annoying is a mild word) is that I had current plans when construction began. I received updated civil plans at least 2 times since then. Layed out same grid line for excavation of spread footing... over ex. by 1 foot so it wasn't caught then.
My last experience with that we were the only ones with the correct plans. This was a 300 by 450 foot structure. The last run of steel was all cut 6 inches short. Three floors by 18 lines...
That's the problem right there. I couldn't care less if the wall moves, but that gridline better not once the IFC set is out.
How can anyone even think it is acceptable to move gridlines. Often that control is set out and literally set in stone (or concrete) before demo begins.
