[Equest-users] eQuest Infiltration Modeling as Airflow (CFM/ft2)

Tue Jul 5 13:35:59 PDT 2022

Looking into infiltration on a leaky building, and thought I'd check out
that reference link Brian referenced (see Brian's response below) in an
earlier post, and found the link has moved to
https://sbcanada.org/wp-content/uploads/2022/04/Air-tightness-Energy-Modelling-for-Part-3-Buildings.pdf.
If anyone was looking for that document, I believe this is where it lives
now.

On Mon, Dec 28, 2020 at 7:14 PM Nicholas Caton via Equest-users <
equest-users at lists.onebuilding.org> wrote:

> Well stated Brian!
>
>
>
> An extra anecdote/caution:
>
>
>
> Brian’s sentiment expressed here – that pressures typical of blower door
> testing for envelope leakage are *atypical* for those found caused
> naturally through wind pressures and other forces for
> infiltration/exfiltration, is correct.  Most of the time.
>
>
>
> If however you are tuning a model expressly to evaluate measures
> specifically affecting infiltration, be mindful that nature likes to play
> outside the box sometimes.  I was tuning a specific laboratory building
> with extremely leaky glazing (partly because the building was a mechanical
> vacuum cleaner, mostly because the glazing was original to the building,
> nearly 70 years old), and was utilizing AMY weather to assist with a
> particularly weather-sensitive and touchy calibration process.  That
> historical weather period coincidentally proved invaluable for this
> exercise, in part because the calibration period it contained some fairly
> extreme weather events… Some wacky looking windspeeds in the Spring caused
> me to google for climactic (?) events in this locality (Illinois), and I
> found just cause for the resulting extreme external building
> pressurization/infiltration: tornadoes!
>
>
>
> Quick takeaway:
>
>    1. While blower door testing is indeed pretty darn extreme in the
>    context of “normal” conditions – nothing is more extreme than mother nature
>    =).
>    2. This also adds a little perspective on the concerns I hear raised
>    occasionally on the idea that blower door testing with existing/aged
>    facilities can harm with respect to building envelope performance… even if
>    true, it’s nothing in comparison with Midwest weather events of this nature!
>
>
>
> ~Nick
>
>
>
> *Nick Caton, P.E. (US), BEMP*
>
> *ニック* *ケートン**, P.E. (US), BEMP*
>
> Senior Energy Engineer
> Energy Manager, Yokota Airbase
>
> ESS - Energy & Sustainability Services
>
> M JP
> M US
> Email
>
> +81 . 070 . 3366 . 3317
>
> +1   . 785 .  410  . 3317
>
> nicholas.caton at se.com
>
> シニアエネルギーエンジニア
> 横田基地エネルギーマネージャー
> ESS - エナジー持続可能性サービス
>
>
>
>
>
>
>
>
>
> *From:* Equest-users <equest-users-bounces at lists.onebuilding.org> *On
> Behalf Of *Brian Fountain via Equest-users
> *Sent:* Thursday, December 24, 2020 8:29 AM
> *To:* Omer Moltay <omoltay at mimtarch.com>
> *Cc:* equest-users at lists.onebuilding.org
> *Subject:* Re: [Equest-users] eQuest Infiltration Modeling as Airflow
> (CFM/ft2)
>
>
>
> [External email: Use caution with links and attachments]
> ------------------------------
>
>
>
> 50 Pa is too high a pressure difference to use for entry into eQUEST –
> regardless of whether you use ACH or cfm/area.  That is a testing pressure
> differential rather than the ambient pressure differential created by the
> reference wind speed of 10 mph (4.47 m/s).  Ambient wind corresponds to a
> pressure differential of ~5 Pa.  Using the n50 flow rate would
> considerably overstate your infiltration load.
>
>
>
> [image: cid:image005.png at 01D6D959.0CBDCB50]
>
> (from eQUEST/DOE-2.2 help)
>
>
>
>
>
> To convert the tested leakage rate (n50) at 50 Pa to the ambient 5 Pa use
> the formula below …
>
> [image: cid:image006.png at 01D6D959.0CBDCB50]
>
> Formula taken from an excellent white paper on modelling infiltration by
> RWDI available here:
> https://sbcanada.org/wp-content/uploads/2017/04/Air-tightness-Energy-Modelling-for-Part-3-Buildings.pdf
> <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsbcanada.org%2Fwp-content%2Fuploads%2F2017%2F04%2FAir-tightness-Energy-Modelling-for-Part-3-Buildings.pdf&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515267558%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=yfhNqxEK1TFs9BEcpDWhRH2SIooG8uDkCV1loWkV2ew%3D&reserved=0>
>
>
>
> Regards,
>
>
>
> Brian
>
>
>
>
>
> *Footprint **Brian Fountain*
>
>
>
> *From:* Equest-users <equest-users-bounces at lists.onebuilding.org> *On
> Behalf Of *Mark Stout via Equest-users
> *Sent:* December 23, 2020 4:03 PM
> *To:* Omer Moltay <omoltay at mimtarch.com>
> *Cc:* equest-users at lists.onebuilding.org
> *Subject:* [Spam released by Allowed List] Re: [Equest-users] eQuest
> Infiltration Modeling as Airflow (CFM/ft2)
>
>
>
> CAUTION: EXTERNAL SENDER
>
> I would use ACH and base it on -50 Pa and the standards the AHJ has set.
> For example, IECC sets some zones to 3 ACH, but the AHJ may/can/do override
> that and may up it to 5 ACH.  Then you just work backwards to arrive at
> ACH, e.g.  the formula for CFM is (5 ACH  ÷ 60 Minutes) x Volume = CFM50.
> Now you know what your max infiltration.
>
>
>
>
>
> On Wed, Dec 23, 2020 at 12:50 PM Omer Moltay via Equest-users <
> equest-users at lists.onebuilding.org> wrote:
>
> Dear All,
>
> eQuest allows inputing of infiltration airflow as CFM/ft2 (of indoor space
> in detailed mode) for every zone.
>
> I have calculated CFM/ft2 values for each zone in my model, but this
> calculation has been done for an outside - inside pressure difference of 50
> Pa. Or I can do the calculation for any arbitrary pressure difference.
>
> The question is, since infiltration is very much pressure dependent, what
> pressure difference does eQuest assume when the infiltration airflow input
> is utilized? I know that it will not take into account the dynamic changes
> in pressure dif. during the simulation due to wind effect or other effects,
> but I just want to be able to input a reasonable value since a calculated
> infiltration at 50 Pa is very different from say, at 5 Pa. The answer is of
> course, at whatever pressure difference the zone is anticipated to be
> operating, so what would you recommend for low-rise commercial buildings?
> Or any other guidance would be appreciated.
>
> Or should I convert my calculated values to ACH and use that input, as
> that takes into account wind speed changes? Again, what is the reference
> pressure dif. to use there?
>
> Thank you,
>
> Ömer Moltay, LEED AP BD+C, ASHRAE BEMP, ASHRAE CPMP
> Mimta EcoYapi, LEED Proven Provider
> Hekimsuyu Cad. 559. Sk.
> No:39 34255 Kucukkoy Istanbul Turkey
> Tel: 90-212-617-2296
> Fax: 90-212-617-2297
> Mobile: 90-533-957-1394
> www.eco-yapi.com
> <https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.eco-yapi.com%2F&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515267558%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=30cXHbejkHUiGgsASx9k7DOWrBkTtwAW0qyFAbIhoWE%3D&reserved=0>
> www.buildingenergymodels.com
> <https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.buildingenergymodels.com%2F&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515277513%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=0QMI%2BwIH%2FTqSFj68jT5N%2F%2B7mPOFYuUmBFOTVdS2KT2k%3D&reserved=0>
>
> [image: cid:image001.png at 01D6D955.0DF3FE30]
>
>
>
> _______________________________________________
> Equest-users mailing list
> http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
> <https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.onebuilding.org%2Flistinfo.cgi%2Fequest-users-onebuilding.org&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515277513%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=MPKgvZt3OYK8xlnxQxvl621zC7N%2BeaCw8n%2BK%2BsUcmdU%3D&reserved=0>
> To unsubscribe from this mailing list send  a blank message to
> EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG
>
>
>
>
> --
>
> Kind Regards,
>
> Mark Stout, President
> HERS I & II, BPI BA, MFBA, RESNET HERS
>
> Lighting & Mechanical Acceptance Testing
>
> CALGreen Inspector/Plans Examiner
>
>
>
> Apollo Energies, Inc.
> 888-614-8338 x101 Office
> 888-614-8338 Fax
> 916-240-2850 Cell
> www.apolloenergiesinc.com
> <https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.apolloenergiesinc.com%2F&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515277513%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=3PWP2Wq%2F7%2F1fTEwpaEEnXnm5%2B6QWJJchmSXV1V5vjKI%3D&reserved=0>
> Follow us on Twitter
> <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Ft.sidekickopen70.com%2Fs2t%2Fc%2F5%2Ff18dQhb0S7lC8dDNfKW3w9sL42B9nMJW7t5XZs5vg7Q8W64zSmC5vMHyMW4XXPpC56dL2ff92xgtF02%3Fte%3DW3R5hFj26QkHjW4mCW-d3K8K1pW43T4NQ45SzBFW43PTww49LkxD2273%26si%3D5947551709659136%26pi%3D2aaf2879-36ea-4628-ebdf-95a2ba6101fb&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515287470%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=t2t4CdJByYPabsDughiDR5VH%2FJIJNMAOuoAJuja2shA%3D&reserved=0>
>  LinkedIn
> <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Ft.sidekickopen70.com%2Fs2t%2Fc%2F5%2Ff18dQhb0S7lC8dDNfKW3w9sL42B9nMJW7t5XZs5vg7Q8W64zSmC5vMHyMW4XXPpC56dL2ff92xgtF02%3Fte%3DW3R5hFj4cm2zwW4mKLS-3ZWVWBW3K2-zv1JxwY5W1Lw3rh45LM6yW1Gyy403yMFyvw1-X_1g47L2%26si%3D5947551709659136%26pi%3D2aaf2879-36ea-4628-ebdf-95a2ba6101fb&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515287470%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=wk0xDVXoGOi%2F61zDyFCzRHnGZs4Tw5N9R1NNrYFVeDo%3D&reserved=0>
>
>
> Subscribe to Apollo Energies Daily News
> <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Ft.sidekickopen70.com%2Fs2t%2Fc%2F5%2Ff18dQhb0S7lC8dDNfKW3w9sL42B9nMJW7t5XZs5vg7Q8W64zSmC5vMHyMW4XXPpC56dL2ff92xgtF02%3Fte%3DW3R5hFj26QkH0W3zbVbk3H6wfQW4cQb1c45SzBFW43PTww49LkxDW4cKKqL1JxwY51V3%26si%3D5947551709659136%26pi%3D2aaf2879-36ea-4628-ebdf-95a2ba6101fb&data=04%7C01%7CNicholas.Caton%40se.com%7Cd28d7a6799bb44a0242508d8a79a8c2d%7C6e51e1adc54b4b39b5980ffe9ae68fef%7C0%7C0%7C637443629515297431%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=q6ipbe8CMBrftThmML%2FpFlM531KA2tUsgCmB4Lvn9Gw%3D&reserved=0>
>
>
>
>
>
>
> DISCLAIMER:  I am not an attorney nor am I an accountant.  The information
> and/or opinions expressed by myself or my affiliates should not be
> considered nor are they intended to provide legal or financial advice to
> any individual or entity.  The information contained in this email is for
> general information purposes only.  Any reliance you place on such
> information is therefore strictly at your own risk.  Apollo Energies Inc.,
> urges you to consult with your own legal and/or financial advisers before
> taking any further actions based on information provided in this
> correspondence.
>
> [image:
> https://t.sidekickopen70.com/s2t/o/5/f18dQhb0S7ks8dDNfKW3w9sL42B9gXrN7sKj6v5dq-KW8r51bz8pTpSnW64JlC63LvrVvW87hWl-1k1H6H0?si=5947551709659136&pi=2aaf2879-36ea-4628-ebdf-95a2ba6101fb&ti=null]
>
>
> ______________________________________________________________________
> This email has been scanned by the Symantec Email Security.cloud service.
> ______________________________________________________________________
> _______________________________________________
> Equest-users mailing list
> http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
> To unsubscribe from this mailing list send  a blank message to
> EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20220705/3b46db16/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 1794 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20220705/3b46db16/attachment.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.png
Type: image/png
Size: 1947 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20220705/3b46db16/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image004.png
Type: image/png
Size: 6510 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20220705/3b46db16/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image005.png
Type: image/png
Size: 59202 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20220705/3b46db16/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image006.png
Type: image/png
Size: 67214 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20220705/3b46db16/attachment-0003.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image007.png
Type: image/png
Size: 44049 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20220705/3b46db16/attachment-0004.png>