Slab on grade drawing preferences 2

[haynewp]

I have seen drawings with floor drains indicated on the slab-on-grade/foundation plans (including ones at that do not require the slab to be sloped),and I have seen drawings with no floor drains with a note referencing to see plumbing. What all would be the reasons to show approximate floor drain locations when a slab slope to them is not required? I would think to check for footing interferences with plumbing.

 

[haynewp]

Regarding coordination, that kind of relates to what I was saying about wanting to see where things are that could affect my structure at that instant in time when I stamp a drawing. If another discipline changes things at the last minute after I stamped my drawing, then at least I have a record of where they were when I stamped the structural.

I have actually also shown equipment pad locations when they are the type that are cast on top of the typical slab and have epoxy dowels connecting the slab to the pad. I don't like control joints going under those so I show them schematically and reference mech for actual locations.

 

[STrctPono]

Regarding coordination, that kind of relates to what I was saying about wanting to see where things are that could affect my structure at that instant in time when I stamp a drawing. If another discipline changes things at the last minute after I stamped my drawing, then at least I have a record of where they were when I stamped the structural.

I have actually also shown equipment pad locations when they are the type that are cast on top of the typical slab and have epoxy dowels connecting the slab to the pad. I don't like control joints going under those so I show them schematically and reference mech for actual locations.

This is the same approach I use. Unfortunately, being correct when the finger pointing starts is useless in the end. Because even if you did everything in your power to show the latest coordination model, if the mechanical changes 1 hour before documents are due, in the end guess who is going to have to update their plans? And guess who is going to look bad in front of the owner and contractor and who appears to be in the wrong? Legally you might be ok... This is why I understand Aesur's stance on the matter. If I know and trust the other engineering disciplines, then I show everything (even if only schematic outlines). If the other engineering disciplines are new to me and I don't know their worth, I am much more wary about cross-discipline items that I show on the plans.

 

[haynewp]

I am kind of selfish in that I put my PE license before anything else and have gotten a little bitter over 25 years. So if there is any chance that the structural design can be affected by someone else after I stamp my drawings, then I want a record of what I was willing to sign. If drains show up beside columns with plumbing lines that interfere with anchors after I issue a set, then I want to show what I knew of at the time I issued my stamped set.

 

[Enable]

As a contractor I'll say that I generally prefer plans that make reference to other DWGs or CDs but don't particularize it beyond that (e.g. locations or layouts). In the case of the OP, if the SOG has plumbing / electrical / whatever I would vastly prefer a note with a leader saying something to the effect of "refer to mechanical for plumbing locations to avoid interference with concreted elements" coupled with another one saying something to the effect of "slope surface to area drains per CDs" or what have you. It's absolutely not necessary but it is a nice reminder for me in case I forget (appreciate the help!), and it also eliminates the inevitable conflicts. When multiple engineers start to put other engineer's work on their DWGs things just have a tendency...to get messed up and I usually have conflicting sets of DWGs (architectural, mechanical, structural, etc) and chasing that down can an endless loop of "ask this dude"

On another note, there is some contractor bashing in this thread and I am sure some of it much deserved. But from the other perspective I have spent the better part of a day reviewing stamped DWGs that a first year engineering student would have known would not be acceptable (no design loads, impossible connections, conflicting schedule items, incorrect weld symbols, specifying non-existent components and specifying particular welds on these non-existent things, etc).

I know construction has become more of a ME sport more so than a team sport over the years. But if we can, lets try and be the people that bring it back to what it once was. We are all in this together!

CWB (W47.1) Div 1 Fabricator
Temporary Works Design

https://www.enable-inc.com/

 

[BAretired]

Words to live by, Enable.

BA

 

[Pmtottawa]

In keeping with the theme of this post.
I came across this awhile back as a detail from a colleague of mine...

P

 

[dik]

Thanks... saved and passed on.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[haynewp]

To Enable’s point, some engineers now are equally as bad.

 

[phamENG]

That may be the best detail I've ever seen...

 

[dik]

That's why I saved it... now to find a good use for it.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[haynewp]

Thanks to all for the input.

 

[STrctPono]

I often work in a world where we are hired by Contractors to value engineer other designs. Whether it be a full redesign or a partial redesign we are usually about 95% successful in getting our design through. I'm not talking about "we can remove 10% of your rebar" type unscrupulous work. This is where we realize the original designer grossly oversized the foundations because they didn't know how to run the seismic or botched the framing plan because they chose the wrong members. Most of these Engineers have no right designing the structures that they are designing. Not only is the overall design bad but the detailing is bad too. I think most of the issues arise when Engineers try to take on new work outside of their comfort zone and don't know the standard of practice in that industry. So to Enable's point, there are plenty of bad Engineering designs as well.

Pmtottawa: Great detail!

 

[Aesur]

I wanted to jump back into this thread to agree that there are many "bad engineering designs" out there as others have said. I tend to see this mostly in over sizing members and lack of lateral designs.

I however also wanted to point out that many times engineering project managers and their engineering "monkeys" will over design members by grouping the members to save time and budget, ie designing a few worst case lintels and using everywhere, same goes for beams, footings, etc.. When a contractor asks for money to "VE" something those fees can be easily hidden in the loans (and most times VE will actually save money overall) and therefore the owner doesn't think much about it; however if the engineer was to raise their fees up front to design every member to provide the most cost efficient design the owner complains because the design fees tend to come directly from their own pockets as they typically cannot raise money for the project until the design and estimates are completed. It is unfortunate that this is the way the market works, however I don't see it changing anytime soon. Many engineers tend to work directly with architects, who too are competing for the project and therefore the lower their fee the higher the chances of getting the project, therefore their is no incentive to provide Value Engineering in the original design budget. This is why it's important to build relationships with developers and contractors, the ones who actually see your worth and how you can save them money on the project, even though your design fee may be higher than others.