Calling all Consulting Engineers

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I think VE shall start from some very fundamental issues from owner and engineer: what is required, what is expected, and what exists. Most time of over budget issue is because owner is expecting more and wants pay less. If the project is way over budget, the owner shall ask architect and engineer to redesign the project, maybe down size the building, or down grade all material especially those fancy architectural stuff.

I think you can provide some recommendations to GC for bidding the job. But any recommendation relating to design change shall be approved by engineer who has stamped drawing when you start the construction.
 
What if

What if

:-? What happens 5-years down the line when the office building owner hires the low bid electrical contractor to replace a breaker and he replaces it with a breaker that is not series rated with the other breakers breakers, theres a fault, the breaker can not handle the available fault current and a sentinel event happens?
 
I'm among the group that really, really dislikes the term "value engineering". My experience is that it seldom adds value , and the people doing it aren't generally licensed as engineers, so it could be construed as practicing engineering without a license. It certainly is the substitution of the judgement of a non-registrant for that of a registrant in most cases.

I frequently have sole source specs on lighting. That's because I run photometrics room by room on my designs. My specs require that photometrics specific to each room (or for the parking area) be provided by the vendor for proposed alternate fixtures. They seldom provide the photometrics. "Equals" seldom are. On one recent job (school gym) the fluorescent high bay fixtures I spec'd gave 80 footcandles. The proposed "equals", major brand, gave 60 footcandles. What I see frequently on site lighting is that my design will use 10 poles, but the "cheaper" fixtures require 12 to 14 poles to get the same levels and the same coverage. In areas that have adopted recent versions of the IECC the VE problem is going to get worse -- standard lay-in troffers generally don't meet the wattage limits, so more efficient fixtures must be used. Most manufacturers have new designs, but the fixtures aren't really interchangeable. In some jurisdictions where I work the ordinances require that the installed fixtures be exactly as specified. There have been a couple of cases where ECs that bid based on generic T8 troffers as subs for the T5 fixtures I specifed were required by the AHJ to remove the generic troffers and install fixtures per plans. That's a costly lesson to learn.

As to fully rated vs. series rated -- it would probably be good to ask the Engineer why he chose fully rated. There's probably a reason. As to "over designed" -- in my opinion "code minimum" designs are generally problems waiting to happen. I'm working of a T.I. in what was supposed to be a office/warehouse strip with each tenant space 20% office, 80% warehouse. The T.I. is 80% office, 20% warehouse. How do you tell the building owner he has to either replace the service or leave a suite vacant because the original design was based on a different type occupancy and there's not enough capacity in the service?

My name goes on the drawings. I'm the one who gets blamed if the lighting is poor -- no one ever remembers that what they installed wasn't what I specified. No one remembers that I specified a 1600A service but they demanded a change to 1200A then ran out of capacity. If they want cheap they can find someone else to do their work. If they want to "VE" they can take responsibility unless they do the work to prove that the proposed alternates rally are "equal".

Martin
 
The disconnect is not clearly defining/understanding the owners exspectations, prioritizing these exspectations and then applying them to a design that fits within the budget for the project. There are true "value engineering" components (ex. ground rods @ light poles, full size nuetrals on 480 volt systems, code demand deversities not utilized) that have to be realized in order efficiently maximize the high priority items. The other "value engineering" stuff is simply realligning how the FIXED money is spent relative to the priorities defined, in the most effiecient manner. If priorities are understoud upfront, and the design is efficient with money focused on priorities and designed close to the known fixed budget there would be little or no "value engineering" required. I disagree that a NEC mimimum design is an accident waiting for a place to happen. The NEC is in place to protect people and property from the hazourds of electricity, shock and fire. I believe it does this very well, maybe to well somtimes (ex. arc fault). I will agree that a code minimum design might not adress concerns such as maintainability, future exspansion, ect but here we are back to the priority thing again. If an owner has higher exspectations than money to spend this needs to be addressed early, early in the master plan or schematic phases of the project by the conulting enginner.
 
hmspe said:
I frequently have sole source specs on lighting. That's because I run photometrics room by room on my designs. My specs require that photometrics specific to each room (or for the parking area) be provided by the vendor for proposed alternate fixtures. They seldom provide the photometrics. "Equals" seldom are. On one recent job (school gym) the fluorescent high bay fixtures I spec'd gave 80 footcandles. The proposed "equals", major brand, gave 60 footcandles. What I see frequently on site lighting is that my design will use 10 poles, but the "cheaper" fixtures require 12 to 14 poles to get the same levels and the same coverage. In areas that have adopted recent versions of the IECC the VE problem is going to get worse -- standard lay-in troffers generally don't meet the wattage limits, so more efficient fixtures must be used. Most manufacturers have new designs, but the fixtures aren't really interchangeable. In some jurisdictions where I work the ordinances require that the installed fixtures be exactly as specified. There have been a couple of cases where ECs that bid based on generic T8 troffers as subs for the T5 fixtures I specifed were required by the AHJ to remove the generic troffers and install fixtures per plans. That's a costly lesson to learn.

Martin
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Don't you owe it to the owner to "design" a system that allows for more than one fixture manufacturer? I used to do Lighting Design all of the time and I would always get two, if not three manufacturer's on the spec. Takes a LOT of the "package" game playing that goes on, out of the picture.


Edit...And why are you designing a gym to 80 FC? That seems like overkill - I believe IES recommends a lot lower level than that.
 
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Engineers Response

Engineers Response

As an engineer, I deal with this VE issue all the time. In an office building, I would accept series rated breakers, because there is no absolute requirement for coordination. In a hospital, there is an absolute code requirement for selective coordination, and series rated breakers don't coordinate by definition so I would not accept them. This would be a very common type of suggestion. I don't see it as adding any quality to the job, but it should meet the code.

I'd also entertain cheaper fixture substitutions. We see this all the time too. From my perspective, the engineer should be open to these ideas, and especially if you call him first. You could ask him if there was a particular quality or look that was intended in the flat specced light fixtures that they were going for, and try to suggest an alternate that maintains that one quality.

Many of these things are habit or seen as higher quality. I generally would rather see fully rated breakers because they are higher quality construction, but not always absolutely required. I generally would rather see copper wire, but I see more and more aluminum these days. I'd rather see hard conduit, but I see more MC cable nowadays, and it saves a bunch of money but makes for a sloppy looking job sometimes. Is a job with hard conduit, copper wire, and fully rated breakers "overspecified"? Not really IMHO.
 
john_axelson said:
Don't you owe it to the owner to "design" a system that allows for more than one fixture manufacturer?
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In my opinion, no. I owe him a design appropriate to the intended use of the project. As I previously noted, in a lot of places I'm no longer allowed by the AHJ to have alternates. Where I am allowed alternates, the only way I know to allow all manufacturers a shot is to use only generic troffers and residential cans with BR30 lamps -- for anything else the distinctives of the various manufacturers' products start affecting fixture performance, which affects the design. Even with generic troffers I'll specify a particular manufacturer and model to set the benchmark.

If you start listing alternates, where do you stop? Lithonia, Cooper, Lightolier, Williams, Hubbell, .... What about second tier suppliers?

And why are you designing a gym to 80 FC? That seems like overkill - I believe IES recommends a lot lower level than that.
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IES recommends 80 fc for a class II basketball court. In this case I also have 4 level switching.

Martin
 
We often get specs for control work that are seriously over designed. I have seen stuff come through that costs 2-5 times what it needs to be to get the job done. We just bid it the way they want and let them know there are opportunities for significant savings if they want to consider options. The CE almost never consider the options. The end users often do.

Not too long ago I designed a system with three small PLCs. The total hardware price for the PLC hardware was under $3000 for the three PLCs and three small operator interfaces total. After it was already built, the CE wanted to change things to save money. His suggestion involved a single PLC and a single OI to control all three systems. I am not sure how this was supposed to save money as the OI he speced out was over $7000 by itself.

Yes I did say after it was built he wanted to change it to save money.

Some of these guys do not have a good feel for what is economical.

I have also run into things that are seriously under designed and just cringe at what is being speced out, just because I know it is never going to work very well.

Sometimes you can get someone to listen, other times not.

As for swapping parts from one vendor to another, sometimes that makes sense and sometimes not. It makes sense if the parts are mostly interchangeable and functionally similar enough, and it does not create a spare parts nightmare. That is the biggest reason I see that people have gone to specing certain parts and certain vendors. You may save a few bucks up front, but you may also have added twenty items to your spare parts stock.

For instance, there is little difference between the diferent brands of IEC starters and terminals. They are so cheap that if they fail you can afford to throw them away.

OTOH, a 200HP VFD is not something you cannot afford to throw away when it fails, and a spare is not cheap, so it makes sense to spec out one model so one spare can back up more than one install in the plant. Other wise you could end up with ten different 200 HP VFDs in the stockroom.
 
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