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Eurocode 1 Wind load on building side walls (external and internal pressure coefficients)

Description:
Calculation of wind load action effects on vertical side walls of building. The net effect of external and internal wind pressure for zones A, B, C, D, E on the wall surface are calculated from the corresponding pressure coefficients
According to:
EN 1991-1-4:2005+A1:2010 Section 7.2.2
Applicable for:
Vertical walls of rectangular plan buildings, flat or inclined roof, and height h less than five times the width b perpendicular to the wind direction, consisting of one skin
Supported National Annexes:
Only countries that adopt CEN recommended values for section 7.2.2 of EN1991-1-4 are supported. The value of the peak velocity pressure can be specified manually. Otherwise automatic calculation of peak velocity pressure is supported, in addition to countries that adopt the CEN recommended values for NDPs, also for the following National Annexes: Finland, Portugal. The National Annexes of Germamy, Norway, Spain, Sweden, Switzerland are NOT supported (enter peak velocity pressure manually).
All Calculations
Input

Hint: Select 'Custom peak velocity pressure' in the terrain category dropdown in order to manually specify the peak velocity pressure.

The terrain categories are illustrated in EN1991-1-4 Annex A. The transition zones between terrain categories are specified in EN1991-1-4 §A.2.
Wind terrain category 0 Wind terrain category I Wind terrain category II Wind terrain category III Wind terrain category IV
Illustration of Terrain categories reproduced from EN1991-1-4 Annex A
m/s
The basic wind velocity is given as vb = vb,0cdircseason where the fundamental value of basic wind velocity vb,0 is defined in EN1991-1-4 §4.2(1)P and its value is provided in the National Annex. Altitude correction may also be specified in the National Annex for EN1991-1-4 §4.2(2)P. The directional and season factors are generally cdir = 1.0 and cseason = 1.0. For particular cases values smaller than 1.0 may be specified in the National Annex for EN1991-1-4 §4.2(2)P.
kPa
m
m
m
Local coefficients cpe,1 are intended for design of small elements and fixings with an area per element ≤ 1 m2 (e.g cladding elements, roofing elements). Overall coefficients cpe,10 may be used for the design of the overall load bearing structure with loaded area ≥ 10 m2.

Orography factor larger than 1.0 may be applicable over isolated hills and escarpments. See EN1991-1-4 §4.3.3 and §A.3 for more details.
Minimum value of internal pressure coefficient cpi to be used when unfavorable. For buildings without a dominant face and where it is not possible, or not considered justified, to estimate ratio μ the value cpi = -0.3 may be used. Otherwise more accurate value may be determined in accordance with EN1991-14 §7.2.9. Enter cpi,min = cpi,max= 0 to ignore internal pressure.
Maximum value of internal pressure coefficient cpi to be used when unfavorable. For buildings without a dominant face and where it is not possible, or not considered justified, to estimate ratio μ the value cpi = +0.2 may be used. Otherwise more accurate value may be determined in accordance with EN1991-14 §7.2.9. Enter cpi,min = cpi,max= 0 to ignore internal pressure.
Nationally Defined Parameters
kg/m3
According to EN1991-1-4 §4.5(1) and the National Annex.
Note: Always verify the validity of the Nationally Defined Parameters. Please inform us of any discrepancy using our Contact Form