ASHRAE Journal - July 2021 - 48
BUILDING SCIENCES
COLUMN
Joseph W. Lstiburek
A.
B.
Site Grading Slopes Ground Away From Building Over Entire Perimeter
Raised Slab
C.
FIGURE 1A, FIGURE 1B AND FIGURE 1C All flood risk is reduced
when the slope of the land directs water away from the
building and when the building floors are located above the
base flood elevation (BFE). Raised slab and elevated pier
foundations tend to be more robust and lower risk than slab
foundations and crawlspace foundations.
Site Grading Slopes Ground Away
From Building Over Entire Perimeter
Designing for Floods*
BY JOSEPH W. LSTIBUREK, PH.D., P.ENG., FELLOW ASHRAE
The best way to design for floods is to build where you don't get floods. Yeah, right. We
have gotten pretty good at predicting flood risk. The Federal Emergency Management
Agency (FEMA) has identified Special Flood Hazard Areas.† We just don't pay much
attention and build there anyway. So if I can't convince you not to build there, I will
try to help you reduce your risk. The new buzzword for this is " resiliency. " And yes,
we were here before-more than once ( " Rebuilding After Katrina, " ASHRAE Journal,
November 2005, and " Rebuilding Houston, " ASHRAE Journal, November 2017).
A bit of background. Three common types of flood
events exist:
* Fluvial (river) floods;
* Pluvial (flash floods and surface water) floods; and
* Coastal (storm surge) floods.
For all of them, the basis of flood resistance or resiliency
includes the following:
* Elevate structures;
* Protect service equipment;
* Ensure that flood waters enter and exit the house;
and
* Design and construct building assemblies that are
able to get wet during a flood event, readily cleaned and
subsequently dried.
*I like to say, " Don't get hit by a wave, don't get too wet, and make sure you dry. " The " Don't get hit by a wave " part comes from the folks
at the Institute for Business and Home Safety (IBHS). I sat through a bunch of their presentations in the early 2000s, and they warned us
relentlessly about how powerful a wave is. I shamelessly have been using their saying ever since. IBHS inspired me to add the " Don't get
too wet " and " Make sure you dry " pieces.
†FEMA's Special Flood Hazard Areas can be found on the Flood Insurance Rate Map (FIRM) at https://www.fema.gov/flood-maps
48
ASHRAE JOURNAL ashrae.org J U LY 2021
https://www.fema.gov/flood-maps
http://www.ashrae.org
ASHRAE Journal - July 2021
Table of Contents for the Digital Edition of ASHRAE Journal - July 2021
Contents
ASHRAE Journal - July 2021 - Intro
ASHRAE Journal - July 2021 - Cover1
ASHRAE Journal - July 2021 - Cover2
ASHRAE Journal - July 2021 - 1
ASHRAE Journal - July 2021 - Contents
ASHRAE Journal - July 2021 - 3
ASHRAE Journal - July 2021 - 4
ASHRAE Journal - July 2021 - 5
ASHRAE Journal - July 2021 - 6
ASHRAE Journal - July 2021 - 7
ASHRAE Journal - July 2021 - 8
ASHRAE Journal - July 2021 - 9
ASHRAE Journal - July 2021 - 10
ASHRAE Journal - July 2021 - 11
ASHRAE Journal - July 2021 - 12
ASHRAE Journal - July 2021 - 13
ASHRAE Journal - July 2021 - 14
ASHRAE Journal - July 2021 - 15
ASHRAE Journal - July 2021 - 16
ASHRAE Journal - July 2021 - 17
ASHRAE Journal - July 2021 - 18
ASHRAE Journal - July 2021 - 19
ASHRAE Journal - July 2021 - 20
ASHRAE Journal - July 2021 - 21
ASHRAE Journal - July 2021 - 22
ASHRAE Journal - July 2021 - 23
ASHRAE Journal - July 2021 - 24
ASHRAE Journal - July 2021 - 25
ASHRAE Journal - July 2021 - 26
ASHRAE Journal - July 2021 - 27
ASHRAE Journal - July 2021 - 28
ASHRAE Journal - July 2021 - 29
ASHRAE Journal - July 2021 - 30
ASHRAE Journal - July 2021 - 31
ASHRAE Journal - July 2021 - 32
ASHRAE Journal - July 2021 - 33
ASHRAE Journal - July 2021 - 34
ASHRAE Journal - July 2021 - 35
ASHRAE Journal - July 2021 - 36
ASHRAE Journal - July 2021 - 37
ASHRAE Journal - July 2021 - 38
ASHRAE Journal - July 2021 - 39
ASHRAE Journal - July 2021 - 40
ASHRAE Journal - July 2021 - 41
ASHRAE Journal - July 2021 - 42
ASHRAE Journal - July 2021 - 43
ASHRAE Journal - July 2021 - 44
ASHRAE Journal - July 2021 - 45
ASHRAE Journal - July 2021 - 46
ASHRAE Journal - July 2021 - 47
ASHRAE Journal - July 2021 - 48
ASHRAE Journal - July 2021 - 49
ASHRAE Journal - July 2021 - 50
ASHRAE Journal - July 2021 - 51
ASHRAE Journal - July 2021 - 52
ASHRAE Journal - July 2021 - 53
ASHRAE Journal - July 2021 - 54
ASHRAE Journal - July 2021 - 55
ASHRAE Journal - July 2021 - 56
ASHRAE Journal - July 2021 - 57
ASHRAE Journal - July 2021 - 58
ASHRAE Journal - July 2021 - 59
ASHRAE Journal - July 2021 - 60
ASHRAE Journal - July 2021 - 61
ASHRAE Journal - July 2021 - 62
ASHRAE Journal - July 2021 - 63
ASHRAE Journal - July 2021 - 64
ASHRAE Journal - July 2021 - 65
ASHRAE Journal - July 2021 - 66
ASHRAE Journal - July 2021 - 67
ASHRAE Journal - July 2021 - 68
ASHRAE Journal - July 2021 - 69
ASHRAE Journal - July 2021 - 70
ASHRAE Journal - July 2021 - 71
ASHRAE Journal - July 2021 - 72
ASHRAE Journal - July 2021 - 73
ASHRAE Journal - July 2021 - 74
ASHRAE Journal - July 2021 - 75
ASHRAE Journal - July 2021 - 76
ASHRAE Journal - July 2021 - 77
ASHRAE Journal - July 2021 - 78
ASHRAE Journal - July 2021 - 79
ASHRAE Journal - July 2021 - 80
ASHRAE Journal - July 2021 - 81
ASHRAE Journal - July 2021 - 82
ASHRAE Journal - July 2021 - 83
ASHRAE Journal - July 2021 - 84
ASHRAE Journal - July 2021 - 85
ASHRAE Journal - July 2021 - 86
ASHRAE Journal - July 2021 - 87
ASHRAE Journal - July 2021 - 88
ASHRAE Journal - July 2021 - 89
ASHRAE Journal - July 2021 - 90
ASHRAE Journal - July 2021 - 91
ASHRAE Journal - July 2021 - 92
ASHRAE Journal - July 2021 - 93
ASHRAE Journal - July 2021 - 94
ASHRAE Journal - July 2021 - 95
ASHRAE Journal - July 2021 - 96
ASHRAE Journal - July 2021 - 97
ASHRAE Journal - July 2021 - 98
ASHRAE Journal - July 2021 - 99
ASHRAE Journal - July 2021 - 100
ASHRAE Journal - July 2021 - 101
ASHRAE Journal - July 2021 - 102
ASHRAE Journal - July 2021 - 103
ASHRAE Journal - July 2021 - 104
ASHRAE Journal - July 2021 - 105
ASHRAE Journal - July 2021 - 106
ASHRAE Journal - July 2021 - 107
ASHRAE Journal - July 2021 - 108
ASHRAE Journal - July 2021 - 109
ASHRAE Journal - July 2021 - 110
ASHRAE Journal - July 2021 - 111
ASHRAE Journal - July 2021 - 112
ASHRAE Journal - July 2021 - Cover3
ASHRAE Journal - July 2021 - Cover4
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XGMDXI
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_YELQLJ
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QJLWMC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_MCDEBX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WNYSQY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XATVOD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FJSHSS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_CCBZDS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XDEFVG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2023november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2023november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VHGNBL
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WPKBNJ
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_UUVCDE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RTGDEW
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2023
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LKRFXS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_AZSOFG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ERCDBH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QWDFRV
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JHGVDF
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OPUYHG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SREIBM
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LRTGLK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OKRFGH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2022november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2022november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TZSERA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LVRUIX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RPTVYZ
https://www.nxtbook.com/nxtbooks/ashrae/mini_pub_catalog
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XIYTGD
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2022
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RFGDOB
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PABXNU
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_REMKLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PICVBT
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_AOYTVW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JQOPLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_IOYTBC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SGAJJF
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_IGHYER
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PDRKLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2021november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2021november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XCODFR
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QSLFGO
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ILKVNM
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2021
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OPDJKD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VJKSRY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDHUTC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JPPKRR
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDLTTH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_CKLLES
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SLDOX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_HJETUK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OLUHGE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ZERDGH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QVMNEO
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RTPOKE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_BBATRE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_STUBMW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TPEMPE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JNMKDS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FBTTPA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WQMMNE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TVBRYN
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2020
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_KTUZMA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ABEDGD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201910
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201909
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019septmeber_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019september
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201908
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201907
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201906
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201905
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201904
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019april
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201903
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019march
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201902
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201901
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2019
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018december
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018october
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2018
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201810
https://www.nxtbook.com/nxtbooks/ashrae/ashraeinsights_201806
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201805
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201804
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201803
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201712
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201711
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201710
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201709
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201705
https://www.nxtbook.com/nxtbooks/ashrae/ashrae_meetinginsert_201610
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acrexindia
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer
https://www.nxtbook.com/nxtbooks/amca/2014summer2
https://www.nxtbook.com/nxtbooks/amca/2014summer
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acma_2014summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201311
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201309
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acmasupp_2013fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201305
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201303
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2013winter
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201211
https://www.nxtbook.com/nxtbooks/ashrae/achr_expo_mexico2012
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201209
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v3
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201205
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201203
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012winter
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201111_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201109_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2011summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201105
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201103
https://www.nxtbookmedia.com