[Equest-users] Adding Insulationtoexistingbuilding(UNCLASSIFIED)

Fri Sep 9 16:08:38 PDT 2011

I have to admit that I read this thread solely because the subject line said, 
"UNCLASSIFIED" :-)
However, having skimmed through what has been written, I take issue with the statement that
adding too much insulation would push up the cooling load by "trapping" internal heat gains.
As has been said, if the outside air temperature is cooler, the internal heat gains can be 
flushed
out using natural or forced ventilation, i.e., an economizer.  But what about when the 
outside air
temperature is higher than indoors?  Well, in that case the direction of heat flow would 
be inwards,
so added insulation would be beneficial!  In summary, my conclusion has been that adding too
much insulation would be ineffectual or not cost-effective, but not detrimental.  The one 
caveat
would be if the increased fan electricity for the economizer is greater than the savings 
in heating
and cooling energy use.

Joe

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 108D
Moraga CA 94556
yjhuang at whiteboxtechnologies.com
www.whiteboxtechnologies.com
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"

On 9/9/2011 3:16 PM, Eurek, John S NWO wrote:
> Classification: UNCLASSIFIED
> Caveats: NONE
>
>
> I did not mean to sound negative towards CERL, I have their web site
> bookmarked.  They are a great asset for information.
>
> I'm assuming we both made energy models.  We likely just used different
> inputs (schedules, plug-loads and 1000 other variable)  I'm very open to the
> idea my model/assumptions are off.
>
> My goal is to find what is most efficient, not to prove somebody wrong.  I
> did talk to the guy for awhile, he gave me so much useful information that we
> didn't dwell on the insulation topic too much.
>
>
> One thing I learned from him was about the ASHRAE Datacom series.  All our
> computer rooms are required to be 72 degrees.  I have seen studies showing
> that a computer room temperature can be higher without endangering the
> equipment, the manufactures even state this.  I think having ASHRAE also
> saying it may help convince owners to allow the computer room temperatures to
> be set a little higher to save a lot of energy.
>
> http://www.ashrae.org/publications/page/1900
>
> -----Original Message-----
> From: Wolfe, Brian [mailto:bwolfe at hksinc.com]
> Sent: Friday, September 09, 2011 3:49 PM
> To: Eurek, John S NWO; Nick Caton; David Eldridge;
> equest-users at lists.onebuilding.org
> Subject: RE: [Equest-users] Adding Insulationtoexistingbuilding(UNCLASSIFIED)
>
> The intent of energy modeling is to understand how to optimize a building's
> efficiency and this clearly shows this is not efficient.  Where's the
> efficiency in installing enough insulation that it drives up the loads of a
> system.  This would negate true optimization and efficiency.  Plus, there's a
> waste of material and cost by adding something that is not needed.  I agree
> that if you are able to optimize the outside air, that would help, but this
> sounds like a misunderstanding of true energy efficiency.  To play off your
> scenarios of examples:  2(heating and cooling loads) - 1(heating) =
> 1(cooling) x 3(increased cooling) = 3(the amount of load caused by super
> insulating)  this just isn't efficient.
>
> I'm on your side that super insulating is not an efficient strategy.
> Increased load, excess materials and extra cost, it doesn't make sense.  I'm
> interested in their reasoning for this strategy being a beneficial one.
> Good luck.
>
> Brian Wolfe, CDT, LEED AP BD+C
> Sustainable Design Coordinator
> HKS  |  Enhancing the Human Experience
> If you are sending large files, please use my Thru dropbox.
> vCard
>
>
> -----Original Message-----
> From: equest-users-bounces at lists.onebuilding.org
> [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Eurek, John
> S NWO
> Sent: Friday, September 09, 2011 2:29 PM
> To: Nick Caton; David Eldridge; equest-users at lists.onebuilding.org
> Subject: Re: [Equest-users] Adding Insulation
> toexistingbuilding(UNCLASSIFIED)
>
> Classification: UNCLASSIFIED
> Caveats: NONE
>
> Today I received an e-mail with recommendations from the Construction
> Engineering Research Laboratory (CERL) and in the recommendations was an R-50
> roof (super insulation).
>
> The recommendations were from the building I ran energy models for and my
> results showed that too much insulation increases energy use.  I hit 'reply
> all' to the e-mail and told everyone that I disagree with their research and
> explained what my models showed.  I received a call from a person from CERL,
> he was a little defensive.  We agreed with everything but the super
> insulation.
>
> I know this will come up in a future meeting and before I go toe-to-toe with
> him and tell the guy he is wrong, I want to make sure I am right.
>
> One of his quotes was "We want the insulation so good that you can heat the
> room with a single match."  I repeatedly told him that it isn't the heating,
> it is the cooling.  He responded with, "the building shouldn't depend on the
> skin to remove heat". I agreed using the skin for cooling isn't the best
> method, but it is what happens.
>
> I would agree with him that super insulation would be great IF the system has
> the ability to bring in a lot of outside air.  The outside air will be 'free
> cooling' minus the fan energy.  The large amount of outside air in essence
> allows you to artificially make the R value zero (just like opening the
> windows)  (*snicker to myself - it is fan assisted natural ventilation*)
>
> Will the ability to draw in outside air solve the problem of increased
> cooling load for a super insulated building?
>
>
>
>
>
> Also, to those who are still reading - A part of the energy modeler's job is
> to understand what is happening then explaining it to others. (Even
> architects)
> The analogies below all involve this building with massive internal loads.
> The architect insisted that you can reduce energy use by optimizing the
> orientation.  I ran the model, it only made a 0.05% difference.
>
> -I told him "It is like trying to get better gas mileage by turning down the
> radio in your car.  The skin load is tiny compared to the servers, lights and
> computer loads."
> -Later I told somebody "It is like trying to make a bull-doze aerodynamic,
> this building is a work horse.  If it were an empty house I would agree
> rotation matters more."
> -And "With this much insulation, the orientation doesn't matter as much. If
> you on the beach in a speedo it matters. If you are in a parka covered head
> to toe, not so much."
>
>
> John Eurek PE, LEED AP
> Mechanical Engineer,
> US Army Corps of Engineers
> Omaha District CENWO-ED-DA
> 1616 Capitol Avenue
> Omaha, NE 68102
> Phone: (402) 995-2134
> email: john.s.eurek at usace.army.mil
>
>
>
> -----Original Message-----
> From: equest-users-bounces at lists.onebuilding.org
> [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Nick Caton
> Sent: Thursday, September 08, 2011 2:52 PM
> To: David Eldridge; equest-users at lists.onebuilding.org
> Subject: Re: [Equest-users] Adding Insulation
> toexistingbuilding(UNCLASSIFIED)
>
> David,
>
> Remind me never to ask you how a thermos works ^_^.
>
> John,
>
> I wrote most of this yesterday and David beat me to the punch... I'm echoing
> much of the same from his response but maybe it'll help as well??
>
> ...
>
> Economizers work just as you describe, and are great energy savers when the
> OA temps are conducive to comfort... (moving air generally takes less energy
> than moving heat + air)
>
> But sometimes it's 110F+ at your RTU in the dead heat of the summer...
> In our local climate and I'm sure many others, the brunt of the cooling
> season has OA temps well above what we want to supply to achieve comfort
> inside.  Economizer function isn't terribly helpful in this situation.
> With too much insulation, you still run into the same fundamental problem of
> "too much heat inside," with no options but to reject the heat using your
> cooling equipment outside, even if you do have an economizer.
>
> Your assertion holds true, that super-insulation can be a non-issue when you
> have an economizer, but only for specific times in the year when the outside
> conditions are cooperating.  Where having an economizer (or not) may have a
> dampening effect on the relative impact/problem of "super-insulating" on an
> annual basis, it could only remove the issue for the brunt of the cooling
> season in a specific sort of cool, temperate climate.
>
> Even in such a climate, blasting tons of extra air into the building to "get
> around" someone's decision to over-insulate the envelope doesn't seem
> ideal... every building should have an envelope construction where "enough is
> enough."
>
> There is an easy answer to your office's water query: "it depends."
> (haha, I'll be here all night!)
>
> There unfortunately isn't a blanket rule here because the answer does depends
> on efficiency of the pumps (or fans), which itself is dependent on the piping
> (or duct) static being overcome (variability of that comes into play for some
> systems), and the efficiency of the cooling equipment as well - be it a
> chiller plant or rooftop DX refrigeration...
> everything balances out and playing with different supply temps/flow rates
> will return a unique answer for every project if you take the time to play
> with it.
>
> ...
>
> As David concludes, this is indeed why modelers are ultimately such popular
> characters =)!
>
> ~Nick
>
> NICK CATON, P.E.
> SENIOR ENGINEER
>
> Smith&  Boucher Engineers
> 25501 west valley parkway, suite 200
> olathe, ks 66061
> direct 913.344.0036
> fax 913.345.0617
> www.smithboucher.com
>
>
>
> NICK CATON, P.E.
> SENIOR ENGINEER
>
> Smith&  Boucher Engineers
> 25501 west valley parkway, suite 200
> olathe, ks 66061
> direct 913.344.0036
> fax 913.345.0617
> www.smithboucher.com
>
>
> -----Original Message-----
> From: equest-users-bounces at lists.onebuilding.org
> [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of David
> Eldridge
> Sent: Wednesday, September 07, 2011 3:50 PM
> To: equest-users at lists.onebuilding.org
> Subject: Re: [Equest-users] Adding Insulation to
> existingbuilding(UNCLASSIFIED)
>
> Nick, my analogy when I talk about coffee thermoses is a metal building with
> internal loads and varying insulation levels.
>
> Anyway - back to the original poster, this phenomenon could more often be
> true where generally it is cooler outside than inside for much of the year.
>
> To reply to John E.'s subsequent post -- there likely will still be some
> hours where it is cooler outside than inside (and the insulation is now a
> detriment) even if there is an  economizer.  Even while the air system is
> providing cooling (whether compressor-based or economizer) the walls may
> still be conducting energy -- they don't stop based on the HVAC system
> status.
>
> Certainly the availability of an economizer can mitigate this problem, but
> might not make it go away completely.
>
> But that's why we have energy models -- insulation that looks great at both
> design days will still have some hours in the middle where it might make
> energy use higher -- run a model and find out what the net is.
> (Unless the building is on Mercury...then always add as much as
> possible.)
>
> David
>
>
>
> David S. Eldridge, Jr., P.E., LEED AP BD+C, BEMP, BEAP, HBDP Grumman/Butkus
> Associates
>
>
>
>
> -----Original Message-----
> From: equest-users-bounces at lists.onebuilding.org
> [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Nick Caton
> Sent: Wednesday, September 07, 2011 3:00 PM
> To: Eurek, John S NWO; mikef at facilitymgt.com;
> equest-users at lists.onebuilding.org
> Subject: Re: [Equest-users] Adding Insulation to existing
> building(UNCLASSIFIED)
>
> Agreeing with John per usual...
>
> Any building with internal loads will have some break-point where adding more
> insulation to the envelope will be detrimental to annual energy consumption.
> It's a bigger deal whenever your internals are relatively high.  The behavior
> you're describing is fundamentally sound.
>
> A good thermos keeps my coffee hot longer (great in the wintertime), but it's
> not the ideal container when my coffee is scalding-hot and I want the
> contents to cool down.
>
> I've yet to settle on a favorite analogy myself... this just comes to mind
> because I need to make a new pot here at work...
>
> NICK CATON, P.E.
> SENIOR ENGINEER
>
> Smith&  Boucher Engineers
> 25501 west valley parkway, suite 200
> olathe, ks 66061
> direct 913.344.0036
> fax 913.345.0617
> www.smithboucher.com
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> Classification: UNCLASSIFIED
> Caveats: NONE
>
>
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> Classification: UNCLASSIFIED
> Caveats: NONE
>
>
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