unless it was an unusually large opening i've never had a structural engineer size the lintel over a wall opening, especially with light gauge studs (maybe masonry).

here's one though and one i've been talking to my coworkers about, in terms of structural connections with detail steel, how much should the architect show, how much should the structural engineer show, and how much can you expect to be provided in shop drawings? at work, we decided that there is no one answer to this and it plays into a larger philosophy of construction documents. are you a minimalist (new school)? or do you show every little bolt, weld, and screw (old school)? the structural engineers i've worked with generally don't show these details in their drawings.

To clarify about my original point, I was thinking of larger openings, you are correct that if it is a simply doorway opening in a light gage wall, it can probably be done with a regular light gage header, but take a glass storefront for example were you may have a string of large openings supporting masonry above. In these cases, switching from a module of 6 or 8 foot openings to 10 or 12 foot openings can easily require a redesigned lintel, especially if the lintel is connected to any sort of canopy or awning. In the end it is primarily a coordination issue, just keep each other up to date of changes, and take the time to really review one another's sets to look out for discrepancies.

Your question is a good one, in my experience, I prefer the architect to show structural elements but not get too hung up on specifics. Use labels like "W-beam, See Structural" and don't get caught up trying to put in the specific size ie. "W18x35". Whenever the architect starts labeling the beam sizes, or even just the depth ie. "W18", it tends to lead to trouble, because commonly the sizes of members will change throughout the process and it becomes a coordination nightmare.

As for the connections, the Structural Engineer normally will design only connections that they deem critical or atypical. Typical connections will be designed by the steel manufacturer. The engineer will then review the connections in the shop drawing phase. This is done primarily for economic reasons. The steel manufacturer will know what is the most economic connection type based on their current stock of materials, as well as manufacturing and labor costs involved, which is expertise and information the Structural Engineer doesn't have. If the Structural Engineer were to design each connection independently you can imagine how the individual connections would be optimized, but as a system, this would add tremendous inefficiency to the manufacturing and installation process which far outweighs the small savings of each individual connection.

i'll usually call out "hss4x4" in the drawings depending on the size of the steel i would like to see used, then send it off to the structural engineer who will either say, "okay," or " you're nuts. make it 8x4". the reason why i bring this up is that we have a third party architectural reviewer who is obsessed with showing the minutiae of the detailing, down to the number of screws to use in the bracing of a light gauge hanging lintel. i really believe this is excessive and a waste of our time and the structural engineers.

but then again there are gray areas. for instance, i am working on a project where we are spanning between two concrete shear walls with tube steel to support a very heavy art piece. the structural engineer has confirmed the sizes of the steel, but has not detailed the connection to the shear wall. we've detailed it as a 1/2" steel plate with anchor bolts. i'm assuming they'll just use four anchor bolts in the corners, but we don't have the type of bolt or embed depth shown. the structural engineer doesn't seem real interested in including this in his drawings. we've already issued the set and if the contractor comes back with an rfi, we'll forward it on to the structural engineer.

anyway, i feel like there is often this tug-of-war of what to show and what not to show, what is covered under contractor means and methods and what will eventually show up as an rfi. the more experienced architects i've worked with have told me you eventually develop a feel for these things, but even then it seems to be a frequent topic of debate.

I can agree to your point about HSS tubes and situations where the profile of the member is critical. If you need a beam to be a W12, regardless if a W14, or W16 would be more efficient, I can understand calling this out, just don't get hung up the specific section. Saying HSS4x4 is a lot better than calling out HSS4x4x1/4.

That connection is definitely an engineers responsibility. Did the SE do the original work on the building, or just the new art support structure? sometimes we get into debates about whose responsible for certain aspects of a design. For example, an engineer may design a massive sign at a storefront, but are they responsible for the connection to the building, or is it the SE on the buildings responsibility? Normally these things should be clarified in the contracts signed, but of course it can get grey as you described.

Do make sure someone looks at that connection, if that piece of art is as heavy as you are saying, it will be important to make sure the plate and anchors are properly sized lest you have a serious and potentially dangerous failure.

I think you're reviewer is asking for trouble, this information is not normally shown in structural drawings and if you show it in architectural plans that is begging for mistakes. As much as possible we let the light gage contractor on our jobs design their connections. We simply provide them with reactions which need to be taken by the light gage and they take it from there.

I see the working relationship problems as being two fold. The first being that younger architects don’t know enough about structures and structural systems and thus run into the problem of making changes that they think will have a minimal effect on the engineering design of the building, but end up requiring a major re-design by the engineer. The second problem is generally structural engineers are too linear about the process and just want to “solve the problem” one time and get it right. Any redesign just makes them bitch and moan, but I get that, because the process to an engineer is much more involved than dropping a new window in an elevation, it requires lots of number crunching and re-strategizing, sometimes revising the whole building depending on how complex changes become. Also, most structural engineers are not creative in any capacity, sad but true. And when they are confronted with anything that would require special detailing, analysis, or would be deemed as irregular by the code they become very uncomfortable operating in that territory and that is where most architects interests lie. It’s paradoxical that two disciplines that couldn’t be more opposite require so much dependence on each other.

i think it would save a lot of time and things would go much more smoothly if in small buildings at least, more architects made the leap to size the members prior to getting an engineer on board. in many cases you don't even need a PE for residential wood framing. working for architects who insist on not sizing beams because they are afraid that some liability will come from this can be a pain. the fact of the matter is if you go into it with a better sense of, for example, the thickness of the floor or roof pack, it saves a lot of time later. doing things just because they "seem okay" adds another step to the process, and can cause problems on the architectural side of things when it becomes obvious that the head height is too low and you have to re-evaluate the design. it also makes it seem like we know less about what we are doing.

My beef with structural engineers nowadays is they over design - especialy in older buildings. Old doug fir wood is almost 2x the E of fast growth southern pine or hem fir. We do a lot of renovations to old warehouse type structures in Chicago and the new details we get from the engineers are way overdesigned. Sometimes the framing layouts Ive gotten from engineers when I worked in construction for a 4 sided gable with load bearing valleys are beyond absurd. i know carpenters aren't engineers but one does become quite knowledgeable about what does and doesnt work. They add triple microlam valleys bolted evry 12" top and bottom, kneewalls, lags etc - I mean c'mon.

Then we have to wait over a week. We are all pressed for time but engineers seem to really be unconcerned about construction schedules.
Currently our contractor proposes a change to cut new 30" duct openings in a 22" loadbearing masonry wall carrying 5 floors and a concrete rib floor system. We were going to use the existing window openings. So this is a better aesthetic solution he has money for ( a rare good fortune) But the HVAC guys are up everyones ass - we need a lintle detail by Tuesday. They've had 2 days thus far - theyve taken off to go to cubs game, they leave early Friday - I mean its a standard lintel - the rib system edge beam carries the inner wythes - sure theres some wall plane shear to calc - but its a 22" wall!!! Theres a lot of meat for the force to go around the hole.

All in all I love structures and structural engineers - but you asked for our pet peeves.

My favorite - although its more by code bodies being sold by manufacturers to include their products - the hurricane straps. I just had to add stainless steel straps to every rafter on an addition to a suburban house in Illinois - the existing rafters are toe nailed and are 75 years old. They havent gone anywhere -

Sometimes i think we are adding unnecessary structure because we are getting worse at building. There used to be an art to nailing - now we just assume everyone a malaka just trying to get home for Miller time?

arrazzzz

good point, I agree with your sentiment. I've noticed that sometimes architects will propose "small" changes that actually require entire redesigns of my structural system, while on other projects they warn me of "major" changes that ultimately require little or not change in my system.

You are also right about structural systems, we prefer continuous load paths and other forms that we can accurately model and understand. I enjoy the challenge of unique systems but these can require large amounts of effort on my part to come up with a solution I'm comfortable with. Initially, I'm often wary of putting this extra effort in when I perceive that a simpler solution is available. It may seem very conservative, but really it is more about providing the fastest possible solution and not intended to diminish the design intent., thought it may have that appearance.

Evil,

I'm aware of the problem with existing structures. The issue is that, without physical testing, Structural Engineers are uncomfortable assuming values for the material strengths because so much is at stake. Not every building, built today or in the past, is the same, and it is a huge risk to assume what the properties are without testing. With proper testing to determine reasonable values, whether it be for for soil bearing capacity, concrete compressive strength or for wood Young's modulus (as you mentioned) we aren't afraid to use full capacity values, but we aren't going to just go around guessing, even with educated values, when so much is at stake. Anticipating this, It might be a good idea to inform the owner of the need to employ a testing agency early in the design process.

Keep in mind that some structures are designed for other parameters than simple strength capacity. For example, a wood floor building might be fine for typical floor loading conditions, but if you want it to be functional for dancing (as in a bar space) it may require additional framing to provide the appropriate stiffness to keep the floor functioning safely and comfortably.

synergy..are you a PE or SE? do you have your own practice?

I'm working towards my SE and do not have my own practice.

Hey Everyone,

How do you handle structural shop drawings (ie. structural steel drawings, rebar etc etc.) Do you typically review them prior to sending them on to the engineers or after they have been returned with mark ups? What types of items do you look at, and what do you not look at?

Anybody?

I review them first then send them on then review them again with comments. Im appalled sometimes at the lack of oversight at some pretty big firms. They stamp the drawings reviewed without really getting into them just to say "ya we looked at them the intent is there but we dont claim any responsibility" When I worked in construction the first thing I was told was the shop drawing approval meant nothing and we had to review them ourselves because we are the only ones who will be responsible.

Its a shame - shops should be a primary function of the architect's office. Its the actual building. Our drawings are technically a representation of the building. But then again, the architect's fee should be enough to properly pay attention to these drawings.

This isnt a blanket statement - some firms are much better than others.

I review them first as well. I've caught a few things like beams that aren't noted at the right elevation. The GC should review the shops before forwarding them to the architect. In my experience they just stamp the shops without looking at them. I just reviewed plank shops that were completely and obviously wrong.

The most important thing with engineers (structural or otherwise) is to have good communication. I make DWF markups of the structural drawings, email them, and then call the engineer to discuss.

I've noticed a similar trend, often the shop drawings bear a stamp from a contractor, but rarely will there be any comments whatsoever.

I really appreciate when Architects pay attention to steel elevations. A lot of times when I'm working on a job there will be things like steel lintels, that I know exist, and I show them in my plans, but I don't have an exact elevation for them. DWF/PDF mark ups really help communicate ideas quickly and are also really appreciated.

I try to go over the dimensions shown on shops, especially the overall grid dimensions and look for any obvious mistakes. I typically mark these up as 'Arch Review' or 'Arch Verify' to communicate any potential errors I find. I think this is the architect’s responsibility, but I think it helps to have a second set of eyes confirm them, and it can help catch any discrepancies between the architectural and structural set.