Hours to Model - Typ Office
From beginners to seasoned pro's, you will always feel like you could have done it faster. Let's say you have a ~20,000sf Office with perimeter individual offices and a central cubby-farm, with the typical breakroom and toilets/janitor closet. Typically these would be a shutoff type VAV system fed from a single VAV air handler (no energy recovery, just economizer). Even if you've never done one please give estimated time: 1. Guesstimate or Modeled 2. Hours spent 3. Climate Zone 4. Did you have to follow ASHRAE 90.1 Appendix G 5. Scale of 1-10 would you consider this task easy 1 or hard 10 6. Modeling software you'd use. Thanks for playing.
Oct 20, 2010
I have modeled at least 6 Barracks for the Army now (190,000sf each, 936 soldiers) and were 2-pipe changeover systems with boiler/chiller. It was my first flurry of submissions to LEED v2.2 and I got some real doozies for comments. I've learned that there is no answer to the ultimate Project Manager question "how long", but off the top of my head I spent 180hrs on each Baracks (cause they weren't all the same, slightly rotated) and another 100hrs on all 3 to get them in shape based on LEED review comments. Energy modeling has become a nemisis of my PM's. I had numerous meetings with them to break it down for them, developed and held conferences internal to our firm, to put it out there. Half didn't show or even want to listen. They think I can do it faster for their K-12 school than the Corps of Engineers (USACE), LEED is LEED there is no faster way, but only the 90.1 way. Some assumed it'd only take 4hrs to whip our design loads into a basecase to compare to. Others have learned that it takes what it takes, since there is a LEED review, if you don't submit it being 100%, the LEED review comments will take you down the path till they are satisfied you have the model correct, according to 90.1. So with that, you know have taken the whip from your PM, and have given them some distrust in Trace700 since you can 'tweak' numbers, and have them questioning your skill level at energy modeling...do not fret. Have patience, let things work themselves out. Fall back on your HVAC background, if you don't have one, you will need one as to fully comprehend the energy model.
Currently working on a Barracks with geothermal W2W chiller for the DOAS/geothermal heat pumps and a dedicated W2WHP for DHW precharge tank. I've probably have racked up 180hrs by now. I'm not finished with the plants to get the energy consumptions correct, and the test wells say that the soil conditions are not favorable, the lot is limited in size, and the depth of the wells are shallower than expected, so it may all changeover to a cooling tower with boiler back up. Which changes my 90.1 basecase from a PTHP over to a PTAC system.
This is exciting and the front line of sustainable cultural shifts, weird but true. Teach your superiors, and teach a newbie college student, be open to constructive critism, and help draw in enthusiastic new talent. Use integrated Design to speed your process, and have some fun with it.
Be Sustainable -- Never let today use up tomorrow!.