What are your most common/frustrating design mistakes?

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steve66

Senior Member
Location
Illinois
Occupation
Engineer
I think you missed my point about the revisions... If the sprinkler plan is dated 2008, and the last revision of lighting is 2009 - means there is no coordination between plans in the event of conflict... If you don't get too many RFI's about this - the client may have already made an economic decision about who'll sort it out for you... ;) Depending on the cost of the trade CO and designer fees. Often it's the plumber shifting... But after we get into a fist fight on site about it.... :D

As far as I'm concerned, the layout of the lights get priority over the sprinkler heads. I've never seen a FP contractor that didn't work around the MEP items we show on the plans.

As far as I'm concerned, it's not my responsibility to redo my entire set of plans just because the FP contractor wanted to save a head or two, or because he ignored the entire set of MEP drawings we made.

Steve
 

e57

Senior Member
As far as I'm concerned, the layout of the lights get priority over the sprinkler heads. I've never seen a FP contractor that didn't work around the MEP items we show on the plans.

As far as I'm concerned, it's not my responsibility to redo my entire set of plans just because the FP contractor wanted to save a head or two, or because he ignored the entire set of MEP drawings we made.

Steve
Thats exactly the additude I'm talking about... Far be it for me to stick-up for a plumber, but since he is often on site before me (Big holes), and revisions to his plans pre-date revisions to an MEP when I get there (Small holes) - but the responce you gave above is exactly what I hear from both sides... Who's in the middle - ME... And often he's 3/4's done with a set of plans you may have equally ignored... Who gets the cost - client... ;) Who gets the blame? We'll find out at the finger pointing party... :roll:

For that matter - I've done remodels where all HVAC is to remain - and then have some lighting designer - who has been to the site, and often - completely ingore the existance of them - even when the A set RCP's theirs were based from contained them as a layer. Visibly over-lapping - right there on paper... Sometimes I just sit back and laugh.
 

steve066

Senior Member
Thats exactly the additude I'm talking about... Far be it for me to stick-up for a plumber, but since he is often on site before me (Big holes), and revisions to his plans pre-date revisions to an MEP when I get there (Small holes) - but the responce you gave above is exactly what I hear from both sides... Who's in the middle - ME... And often he's 3/4's done with a set of plans you may have equally ignored... Who gets the cost - client... ;) Who gets the blame? We'll find out at the finger pointing party... :roll:

For that matter - I've done remodels where all HVAC is to remain - and then have some lighting designer - who has been to the site, and often - completely ingore the existance of them - even when the A set RCP's theirs were based from contained them as a layer. Visibly over-lapping - right there on paper... Sometimes I just sit back and laugh.

First of all, I've never had anything like this happen on a project.

But, it's not an attitude. I'm not going to move the lights on my plans because I placed the lights where they are shown for a reason. Its called design. I place the lights for the right amount of light with even distribution. And the lights go in regular spacing in nice regular patterns. I'm not spacing 2 lights at 12' apart and the next 2 at 8' just to make the FP contractor's life easier.

And if this did happen, the client wouldn't be paying for corrections. And the electrical contractor wouldn't be in the middle either. The FP contractor would be moving their stuff - end of story.

You are blaming engineers for the FP contractor's work.

Steve
 

e57

Senior Member
You are blaming engineers for the FP contractor's work.

Steve
Actually no I'm not.... I'm blaming individual members of a "Design Team" who think "Me First" and act as individuals - not a team. The type of people ignore site conditions, and other design elements, as well as performance of systems and structures outside their scope - kinda contradicts "team". What you end up with is several conflicting aspects of a building as a whole... Sometimes the conflicts are minor - sometimes they're not - but all avoidable IMO.

In the last several posts FP and HVAC were used as an example - but the problem is endemic, and manifests itself in many other ways too. But much of it can be avoided. When one person says - "Its called design." Often there might be other people present who might think to themselves - "It's a structural element" - "It's riser." - "It's a vent." - "It's a fire rated ceiling?" - "There goes that boat payment..." and - "Did he really mean to say that out loud?" Sorry - but you really need to re-examine your last two posts - because they are prime examples of what I was trying to say...

Eventually after the arm wavers and shiny shoes leave - we'll sort it out on our own... ;) I learn a lot about other trades that way. Much like lighting an area - the FP guys aren't just trying to detect a fire - they want to put it out. HVAC guys want to heat or cool an area. Framers and concrete guys are trying to hold it all up. Etc. And all of those depend on placement and physical space... Each of them has a building code, and inspections to pass...

In the immortal words of Rodney King - "Can't we all get along..."
 

M. D.

Senior Member
.......
........Smoke detectors have become a non-issue in most of my buildings now as they are fully sprinkled. (Notification is by the sprinklers, not by smoke detectors now) I only need duct detectors as required and a smoke above the FACP.


Is this true for schools ? seems to me you would not want to wait until the sprinklers go off and or rely on a smoke in the duct ? What temp do they pop.
I would bet the school would be filled with smoke way before the sprinkler goes off.
 

M. D.

Senior Member
My wife , a teacher in a new building, doesn't understand the lack of receptacle outlets also she says the motion sensors on the lights shut them off when she is alone working at her desk ,.. very annoying,. she requests some sort of override ...
 

nhfire77

Senior Member
Location
NH
Imho

Imho

I am always amazed that engineers will sign off an alternate design stating Duct Smokes are sufficient. Its not true. I have been a professional firefighter for 12 years, I have seen fires in spaces where duct smokes where all there was for smoke detection and they are never the first thing to go off, or never activate at all. The sprinklers are. Which is fine, if you don't mind the water and excessive smoke damage. If there were spot smokes, we would have been there sooner, maybe even before the sprinkler head popped.

Smokes offer much earlier protection than sprinklers. I know false alarms can be annoying, and they really don't have a prayer of working correctly in a large open space 30 feet up, like a warehouse, but office buildings/mercantile should have them. Duct smokes, just like heat detectors, are not a true life safety device.

How about beam detectors for large open spaces? You don't see a lot of those going in, but they are an option they are pretty much avoided on the design end of it. I don't understand why, they are not that complicated;)

Why do we require smoke detectors in all new homes all over the place? Because they work!!!!!! Homes are not commercial offices, I digress.

Since I primarily deal with fire, i might seem biased, but a properly designed and installed fire alarm system will save lives and reduce property damages (hey its all about the $$$ these days) in the event of a fire.

This is not to say sprinklers, should not be installed, just that they should be installed together.

Again, the nuisance alarm factor is a big deal, both on the annoyance for the fire department and the business lo$$ from evacuating the building for nothing. The new intelligent smokes, and the new multi-criteria devices, which will be coming down in price soon I am certain of that, is what we should be installing. From my limited experience I have seen almost no false alarms from intelligent/addressable smokes. Most of them tell you when they are dirty!!!! So if there is a false alarm, and we can see that is was in trouble just before in went into alarm, its not really a false alarm, its poor maintainence, which is a topic for another thread
 

tryinghard

Senior Member
Location
California
most office buildings will have the bathroom ex. fan(s) controlled by the BAS (if there is one) one hour before employees arrive 'til one hour after they leave. The fan needs to be running non-stop in the men's room for sure.
In Calif is this title 24 compliant?
 

tryinghard

Senior Member
Location
California
Include:
  • feeder & branch home run schedule
  • appliance with spec schedule
  • equipment with spec schedule
  • load calc all panels & distribution
  • lighting schedule with spec and quantities
  • complete electrical noted on E sheets not tucked away in A's
  • revision of all items above with RFI's and CO's
 

steve066

Senior Member
In the last several posts FP and HVAC were used as an example

I guess I'm not following the examples, because it still sounds to me like you are blaming the engineer for the contractors negligance.

In the last several posts FP and HVAC were used as an example - but the problem is endemic, and manifests itself in many other ways too.

If those are just examples, I don't think you ever said what the "problem" actually is.

but the problem is endemic

Again, I don't think I've ever had anything remotely like that happen.

The closest thing I can think of is when a HVAC contractor completely ignored a very specific note we had on the drawings that said "put your duct here". But in that case, everyone worked together, and the lighting layout was revised in the intrest of meeting a construction deadline. I don't think anyone thought it was a problem at all.

However, I think we are hijacking Ptrip's thread. Why not start a new thread so we aren't posting in the middle of other unrelated posts?

Steve
 

e57

Senior Member
I guess I'm not following the examples, because it still sounds to me like you are blaming the engineer for the contractors negligance.
I'm not blaming anyone specifically - see below:


If those are just examples, I don't think you ever said what the "problem" actually is.
The "problem" as I have mentioned several times before - is that two or more sets of plans can co-exist on the same project and remain in conflict until the two crews from different trades meet on the job. The plans themselves may have existed for eons before the workers for each trade got them. They were in the hands of the designers of each. Each of those designers and/or engineers has been focused on theirs alone - without looking at - and from the sound of it - acknowledging the mere existence of the other... Yet each designer and/or engineer continues to revise their respective plans - and they can care less... They say, "It's not MY job..." or "It's not MY problem..."

Who's job is it to resolve these conflicts? I know it's not mine - I need to do what is on MY set of plans. But when I get there - other trades who may have been there for months before me have been installing what is on their plans. But in that mean-time someone may have been still revising MY set of plans - and still could care less about that other stuff... :roll: I get on-site - and there is already something there where the lighting is supposed to go... Me and the Foreman of that other trade pull out our plans look at the dates... His is often OLDER - much older... Yet now we need to resolve it... I send an RFI to the GC - who comes out - looks at - shakes their head in the typical manner - we all curse the names of the people who generated the cartoons in question... The RFI usually stops right there - a CO is generated - often to the other trade to move said item... Why - because my item is often aesthetic... The person who ignored the conflict for ages before this - never gets the RFI or the CO - never gets his little feelings hurt...

That said - it really funny when they are on the same page over-lapping - it makes you wonder how many people are asleep at the wheel.
Again, I don't think I've ever had anything remotely like that happen.
I'm not sure you would notice or care if it did - it may have been resolved without you...

FWIW - What I don't know about sprinkler placement could fill a book - but - what I do know is that lighting can not occupy the same physical space.
 

scott thompson

Senior Member
Per "e57" original topic - regarding Light Fixture placement -vs- Fire Sprinkler placement:

In my Designs (Cold Storage + Dry Storage Warehouses), the Lighting Layouts are _ALWAYS_ compared to the -MOST CURRENT- Sprinkler layouts.

The Lighting layouts will have dimensional notations for the Field Crews to use as the actual layouts on site.
Prior to the Lighting layouts + dimensioning, I obtain the most current version of the Sprinkler layouts, and overlay it to my Lighting Plan(s).

Sprinkler layouts are one of several Design variables to adjust around; Evaporator placements, racking layouts, RTU Plenums, Structural elements, and Refrigeration piping layouts... these all impact my overall Design.

In these Design / Build Projects, there is no possibility to just neglect "The Other Guy". We all conferee with each other during the Design Phases, and through the Development Phases.
This "We" list includes:
Architectural, Mechanical, Refrigeration, Structural, Plumbing, Equipment Vendors, Client's Representatives, as well as Me (Electrical).

Fire Sprinkler layouts fall in specific orders per Project, and have specific requirements per area served -vs- flow and coverage.

In some cases, there may not be any Lighting Fixtures (or other types of obstructions) within a 24" Diameter of the Sprinkler Head - mounting is +12" above the Sprinkler; no obstructions may be less than 120" below Sprinklers.

Scott
 
How Design SHOULD work

How Design SHOULD work

Design in Ideal environment:

the mechanical,electrical,plumbing, and structural engineers and architects all work for the same company.

all engineers and architects reference in other designers ceiling layers on their plans, so any changes are known to other designers instantaneously.

The fire protection engineer does the complete sprinkler design by showing exact head locations

All ceiling stuff coordinated perfectly, everyone happy!!

Design in the Real world

one company for architects, one company for structural engineers, one company for mechanical/electrical/plumbing engineers.

BECAUSE separate companies, ceiling plans normally only coordinated ONCE at end of 100% design phase (stuff still missed here, normally because architects give final ceiling plans to designer a few hours before design is to be finished).

Although the LATEST fire protection plan may be OLDER than latest Electrical plans, chances are slim to none that the Electrical designer has ever seen these plans ONCE as they are prepared by the contractor, approved/reviewed by the fire protection engineer and that's the end of plan changes. Electrical design drawings continue to change after the sprinkler plans are finished as Architects move a wall here or there, change a door swing, the owner adds some more equipment that needs power, etc.

NO ONE wants to pay an engineer/designer to coordinate ceiling plans. Just as contractors are squeezed by the owner on cost, so are the engineers by the architect. Engineers get paid by the architect who gets paid by the owner. The architect has an incentive to cut the engineers fee as much as they possibly can so they can keep more for themselves, so while they will pay for an engineer to do one coordination at the end of the 100% design phase, they won't pay them to coordinate for the addendums and owner requested changes. A good architect checks every engineering drawing every time a change is made after the 100% design and has the engineer change his drawing or has the GC notify his subs that something will have to move. Many architects do not do this.

Contractors should be frustrated with uncoordinated plans, but just as designers don't have an appreciation for the installation process, I don't think contractors have a full appreciation for the design process. Designers have similar issues as contractors, (tight budgets and tight deadlines). On limited budget, tight deadline job (pretty much all of them), attention to ceiling coordination is not #1 priority as it doesn't cause a change order that the designer may "see". Failing to upsize circuits for all of the HVAC equipment because the mechanical engineer added electric back up heat at the last second is what keeps an electrical designer up at night.
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
I did not take the time to read all the posts so excuse me if I duplicate.

Specifiying materials that are not available and have not been available for years. Seeing references to a owner "Z" in a project that was supposedly designed just for customer "X". Really makes an impression.
 

ptrip

Senior Member
I did not take the time to read all the posts so excuse me if I duplicate.

Specifiying materials that are not available and have not been available for years. Seeing references to a owner "Z" in a project that was supposedly designed just for customer "X". Really makes an impression.

I've definitely been guilty of that. :roll:
 
#1 problem with designs from architects and engineers:

#2 on printed drawings: Not specifying conductor insulation and conduit type. Just labeling the drawings as #4 Cu in 3" conduit does not help me to do fill calculations.




That is often covered in eitehr of 2 places:
  1. In the specifications, or
  2. Cover sheet of symbols and common notes.
It not efficient to reproduce sommon information repeatedly AND it also makes the drawing less crowded, easier to read. Drawing supposed to be a pictorial representation therefore minimal verbiage should be used. An spreadhseet cable and conduit schedule is even better as it helps that Contractor with takeoff summaries of conduit, wire and cable. Each cable run is either tied to one end of the run, eg. it either is derived from the equipment tag or the panel/circuit designation.

My other pet pee-vee in design is to have information only in one place, so if it changes you don't have to worry about all the other places and confusing the installer which one is valid.
 
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I don't do arc flash calculations (since it depends specifically on the gear and equipment used, and I don't know that until I get submittals).

This probably the biggest issue in providing a well designed and installed project and neither the Designer or the Contractor is at fault. The business model is at fault. (One of the reasons is that the Contractor is trying to make profit on the equipment and certainly should not be blamed for it.)

Equipment is commonly specified in general terms for the Contractor to procure and X, Y and Z does not necessarily coordinate with A, B and C devices. The T/C curves vary sufficently that coordination and arc-flash energy will vary. The Engineering firm is seldom given money to complete the studies post IFC.

Somebody also mentioned the designer/engineerreading of the OEM manuals. The reason above also precludes that. They plainly do not know what equipment will be used and can't make allowances for it.
 

bdktoys

Member
Location
York, Pa.
I work for an engineering firm and do all the field management. We have the conductor insulation and conduit type in the specifications of the project manual.
The project manual and the construction drawings together make up the construction documents.
The problems we have is that the contractors do not read the specifications...
 

sameguy

Senior Member
Location
New York
Occupation
Master Elec./JW retired
Not pointed at you, per say.
Do not scale print. Then give us all the numbers.
Get in the field more to see what you made.
Coordinate between trades before releasing prints.
What is with the, If I left out or don't know what I'm doing you should and at the highest cost blahh blahh cover axx line in the spec.?
I had a long post but timed out.
 
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