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Damage by Electrical Contractors 5

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medeek

Structural
Mar 16, 2013
1,104
US
The picture below is a recent repair job that I worked on. Single story commercial building in a 155 mph (ult) wind zone. Over 60% of the gable end wall was compromised. The fix was both presciptive and engineered. Any thoughts on what you might do?

electrical_holes.jpg


I guess this is a good example of "What not to do as an electrician" or any other trades person for that matter.
 
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The newest pictures seem to reinforce that the problem didn't lie with the contractor, but with the MEP engineer, and his lack of communication with the architect.

It's poor engineering, to stick your head in the sand and issue out drawings you know cannot be built,or maybe it's worse, when you really have no idea if it can be built.

This is a fairly small project, but these problems tend to scale up with the size of a building ,at which point ,it's next to impossible to get direction on how to proceed with a fix ,to such a poor design. The endless stream of RFIs that get shuffled from one office to another, with no one willing to admit culpability. " Have the electrical contractor stand there and hold up the wall for the life of the building." Typical... "have the contractor pay for my piss-poor design...he should've seen this at bid. I spent 6 months designing the thing, hell, he's got two weeks to put a price together, and find all my mistakes".

I just reviewed a set of plans, quarter billion dollar range. There must be at least 18 months and a few hundred thousand spent to get to this bid set.15 minutes into the drawings. Hey, the column enclosures are so tight, the specified fireproofing won't fit behind the drywall, let alone the piping that is shown in there too. Call the MEP engineer ..."well, the architect has my revit file"...Call the architect....."Submit RFI's on a case by case basis"....So now the contractor has to spend his resources to get the engineer and architect to communicate with each other. Whatever happened to the AIA guidelines.

Put out an incomplete design and call it coordination for the contractors.
 
Looks familiar.

Install a flat 2x4 on each side of the 2x6. 90 degrees to the stud.
 
hvacpiper, I don't know what it is nowadays, but these type of problems are too common. I bet all of the units are independently metered with one service room. This was an obvious problem from day one. Some of the architects I deal with today seem to be more like cake decorators, rather than what their job is intended to be. I suppose you are correct that it should be the MEP eng that speaks up and suggests there is a problem, but an experienced architect should anticipate this type of problem and build a sacrificial service wall if they cannot live with surface mounted conduit. One Architect we work with can tell me everything about his silly furniture (one floor plan dwg file was 15Mb), yet, his understanding of how things goes together is very very poor. I get why, their clients are most interested in talking about those features. They seem to forget their clients unspoken interest in avoiding field problems.

So why is it the architects still get paid magnitudes more than the engineers that figure out the nuts and bolts? hmm, I think we engineers need to work on our branding. :)
 
This a good object lesson for the younger engineers out there. Just because you're a structural engineer doesn't mean you don't need to be aware of what the other trades need to do.

We had a long skinny two story school building with the electrical and IT rooms on one end. Contractor elected (no guidance on the drawings) to run 40 conduits under the slab and then up the nearest interior transverse shear wall. The sill plates and double top plates looked worse that this picture because he spaced the damned things out, thinking that was better. The holes in the sill plate were large just to make sure they fit over the electrical stubs coming through the footing. Of course the sill plate split and don't even think about having effective end distance on the sill bolts. Oh, did i mention it was supposed to be a double sheathed shear wall. Now I insist on a seperate electrical chase on the structural drawings and make sure the architect does the same.

Plumbing and mechanical can do similar things. Make sure you see the ducting drawings before plan check.

Mistakes/screw-ups are the worst/best teachers. Murphy's law - If it can happen, it will.

LonnieP
 
I agree with you Brad805 we don't get paid enough or seem to get as much respect as the architects.

I was going to work for a company about a year ago that designed timber trusses for high end homes and commercial projects, mostly what they were going to hire me for was my artistic/design ability. However, I also mentioned that I was a licensed PE and that as an added bonus I could also do the structural analysis of the trusses and eventually write some software that would automate this process for them for the most common truss types.

Their response was, "We're not really concerned with the engineering of our timber trusses, we just need them to look nice. We can pay any engineer a couple hundred bucks to make sure they actually work". I was a little surprised at the lack of respect towards the engineering discipline, needless to say I did not end up working for these guys.
 
The thing about this is, it isn't possible for the Structural to know it is coming. Have had a few podium slab projects with (3) stories of wood on top. I knew there would be punching shear issues with all the conduits at the electrical room so I asked the MEP engineer for conduit size/number/layout. His response, "I cannot give you that, it isn't in my scope". The MEP engineer simply doesn't care in many (most in my experiences)instances when dealing with residential of any size.
 
There's no way any party can foresee every issue that may pop up in a building design.

That being said, it sure seems like building design has taken on a much more linear progression lately... Architect-> Structural-> MEP -> Out to bid. Without cycling the design through the chain once or twice, these conflicts are bound to be there.I think it's unfair to dump all the responsibility on the contractor. They just do what the drawings tell them to..
 
Architects = Cake Decorators

Star for you!
 
We have collectively entered a very interesting profession. I suppose it has always been us against the contractors, but that is not correct in my view. Our ultimate goal should be to achieve our clients project goal. When we were working for architects the mindset used to be 90% of our job virtually complete once our deliverables were handed over.

Our company does the engineering for a precast concrete company now and I see consultant drawings from all over the province. Some of them I look at and wonder in dismay how they expect the contractor to complete the project. One project that was tendered in our area years ago mimicked the shape of an eagle. There were endless curves in the project. The architectural drawings had some limited dimensions on the plans and a ton of generic details that they expected the contractor to interpret and figure out the appropriate material quantities for bidding. The engineers drawings only had gridline dimensions and some key dimensions in the sections. How that design team hoped to avoid endless RFI's was beyond me. It came in way over budget and was re-designed....shocking.

The question that puzzles me, is how can we fix it? Projects are getting more and more complex and the bottom line is more and more important for growing companies. The other reality is extra's are big business for many contractors. I know of contractors that have a senior staff member that go thru bid documents to find all of the loop holes and reduce their price knowing full well they will charge an inflated extra later. Some may say BIM will solve this, and it can to a degree, but I see many are using this largely as a dog and pony show. This is not always helpful. There are endless ways to add generic details with BIM if you are working with traditional firms that have specific 2D detailing teams. Another question I wonder about is how do we get our clients to go thru the boring, but important questions during the design process? Increasing fees to allow for additional review time might help, but many firms simply do not have the staff that can find these type of problems. Our insurance company has reported that the most common cause of fault in claims has been traced back to under qualified staff in most cases. Then there is the inevitable problem convincing an owner they should pay more. Many owners do not appreciate the complexity of a building project, and it is difficult to convince them of the importance of these type of questions until we end up debating the "who pays" question. We have not worked for an architect in years, and work mainly for design/build contractors that we have cherry picked. Even though they are the builders I still struggle at times to get them to want to look thru documents and try to anticipate problems. I have elected to ask them endless questions one by one. Not too many questions at once or you will not get an appropriate level of review. The problem with this method is it is tedious and only works for projects up to about $15mil in value.

medeek, I understand your truss interest more now. I recall talking with a truss engineer years ago. He was paid $75 to seal each truss sheet. On the topic of owner interest, our insurer polled owners and engineers separately on the most important aspects of any building project they undertook. I forget all of the questions, but what did stick in my mind was how dissimilar the owners interests were compared to the engineers. I seem to recall almost 90% of the owners put cost and on-time first. I suspect most of those owners simply assume that engineers cannot make mistakes or would ever miss something.
 
The differences between the USA and the UK/Europe are endlessly interesting to me. What sort of building is this and what is it used for. What would be the external cladding and what are the walls covered with on the inside. A small industrial unit where I live in England would usually be a portal framed steel construction clad with twin wall foam insulated plastic coated profiled steel sheeting. The dwarf walls below the cladding would usually be concrete blocks or maybe brick. There are very few wooden buildings and when it is used it is usually clad with brick. Most domestic housing is brick built.
 
Wooden houses (singe-family size) tend to be more and more a wooden frame with only a brick facade (non-load bearing). (I'm talking Belgium here)
Mostly for passive or low footprint reasons: they are much more thermally isolated than classis (= brick) houses.
 
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