Title and InstructionsDate:4/9/14Job Name/Description:Drax
Pellet Mill BuildingJob Number:214039Prepared By:DMApproved
By:SLRevision 008; 2013-Apr-22
Included in this workbook are numerous worksheets to aid in the
sizing of primary and secondary roof drainage systems. The
worksheet tab "Rectangular Weirs" provides the the flow or required
size for a square weir or scupper. The worksheet tab "Rectangular
Weir Tabular" includes common sizes and hydraulic heads for a quick
look up. The tabs "Triangular Notch Weir" and "Triangular Notch
Weir Tabular" is similar but used for triangular weirs. Pipe inlet
flows is simply to estimate the flow through an interior roof drain
into a pipe. The inlet flow will indicate roof drain bodies larger
in size than the typical building code requirements for conductors
or leaders. The project information at the top of this sheet fills
in the entire workbook.The various calculators list "Runs" these
are all identical calculations which allow you to do multiple
conditions on the same form.
1. The cells which are colored light blue are those which the
user fills in.2. The cells which are colored light purple are the
resultant calculated values
Gutter and Downspout SizingDate:4/9/14Job Name/Description:Drax
Pellet Mill BuildingJob Number:214039Prepared By:DMApproved
By:SLRevision 008; 2013-Apr-22
Roof Drainage DesignGutters and Downspouts
Calculations Based on SMACNA Architectural Sheet Metal Manual,
Fifth Edition
Assumptions:
Gutter and Downspout Size CalculatorRun 'A'Run 'B'Run 'C'Run
'D'Run 'E'Vertical Adjacent Wall Area in Square Feet
(AWall)0200050001000020000Roof Area in Square Feet
(ARoof)2140200050001000020000Number of Downspouts41235Rainfall
Intensity in Inches per Hour (I)8.6012.0012.0012.0012.00Total
Length of Gutter in Feet (L)635075100200Depth to Width Ratio
(M)1.6181.6181.6181.6181.618ResultsCalculated Area for Drainage
(ATotal)2140300075001500030000Flow in Cubic Feet per Second
(CFS)0.4260.8332.0834.1678.333Flow in Gallons per Minute
(GPM)191.2374.0935.11870.13740.3
Gutter Width in Inches (W)37788Gutter Depth in Inches
(D)512121313
Req'd Downspout Area in Square Inches
(ADownspout)728505050Recommended Downspout Depth in
Inches26677Recommended Downspout Width in Inches45988
ATotal = (AWall * 0.5) + ARoofQ-CFS = A (SF) * I (In) / 12
(In/Ft) / 60 (min/hr) / 60 (sec/min)Q-GPM = Q-CFS * 7.4805 (CF/GAL)
* 60 (Seconds/Min)W = 0.0106 * M^(-4/7) * L^(3/128) * ((I *
ATotal)^(5/14)D = W * M
Downspout Sizing Lookup
TableDiameterAreaSqIn/SFCFH/SqInCFM/SqInGPM/SqInMaximumGPM3791175.9161.2659.46466.24412110091.6661.52711.428137.135191280106.6661.77713.298252.666281400116.6661.94414.545407.267381559129.9162.16516.197615.48Not
included in SMACNA8501750145.8332.4318.181909.05
Notes:Refer to SMACNA Architectural Sheet Metal Manual for:1)
required sheet metal gauge for gutters, downspouts, straps, etc.;2)
spacing of vacuum break chambers in downspouts;3) spacing of
expansion joints;4) other details of construction.
Rectangular Weir Sizing Date:4/9/14Job Name/Description:Drax
Pellet Mill BuildingJob Number:214039Prepared By:DMApproved
By:SLRevision 008; 2013-Apr-22
Roof Drainage DesignRectangular Weirs
Calculations Based on Cameron's Hydraulic Data Seventeenth
Edition
Assumptions:
1. Roof parapet extends at least three times the height of the
weir or scupper beyond the edges.2. The width of the weir or
scupper is at least four times the allowable depth of water.3. When
calculating scuppers allowable depth must be limited to 1" less
than scupper height.4. Weir sized based on a derivation of the
Francis Formula
Roof Drainage Weir Size CalculatorEnter Input ConditionsRun
'A'Run 'B'Run 'C'Run 'D'Run 'E'Run 'F'Vertical Adjacent Wall Area
in Square Feet (AWall)100020005000100001000020000Roof Area in
Square Feet (ARoof)100020005000100001000020000Rainfall Intensity in
Inches per Hour12.0012.0012.0012.0012.0012.00Depth of Water above
Weir's Lower Edge in Inches (1,2)3.003.003.003.003.003.00Number of
Weirs111111ResultsCalculated Area for Drainage
(ATotal)150030007500150001500030000Required Weir or Scupper Width
in Inches132664127127253Required Weir or Scupper Width in
Feet236111122Flow at Input Conditions in Cubic Feet per Second
(CFS)0.420.831.392.782.785.56Flow at Input Conditions in Gallons
per Minute (GPM)1873746231,2471,2472,494
Q-CFS = 3.33 (L - 0.2*(H/12)) * (H/12)^1.5Q-CFS = (A * (I / 12))
/ 60 / 60Q-GPM = Q-CFS * 7.4805 (CF/GAL) * 60(Seconds/Min)
1) Allowable depth as determined by structural systems' water
load capacity2) The depth excludes the distance from the rim
elevation of the roof drain to the bottom of the Weir
Weir Discharge Capacity CalculatorEnter Input ConditionsRun
'A'Run 'B'Run 'C'Run 'A'Run 'B'Run 'C'Length (width) of Weir or
Scupper in Feet1.08300000Depth of Water above Weir's Lower Edge in
Inches (1,2)300000ResultsFlow at Input Conditions in Cubic Feet per
Second (CFS)0.430.000.000.000.000.00Flow at Input Conditions in
Gallons per Minute (GPM)19300000
Triangular Notch Weir SizingDate:4/9/14Job Name/Description:Drax
Pellet Mill BuildingJob Number:214039Prepared By:DMApproved
By:SLRevision 008; 2013-Apr-22
Roof Drainage DesignTriangular Notch Weirs
Calculations Based on Cameron's Hydraulic Data Seventeenth
Edition
Assumptions:
1. Roof parapet extends at least three times the height of the
weir or scupper beyond the edges.2. The width of the weir or
scupper is at least four times the allowable depth of water.3. When
calculating scuppers allowable depth must be limited to 2" less
than scupper height.4. Weir sized based on a derivation of the
Thompson Formula
Roof Drainage Weir Size CalculatorEnter Input ConditionsRun
'A'Run 'B'Run 'C'Vertical Adjacent Wall Area in Square Feet
(AWall)100020005000Roof Area in Square Feet
(ARoof)100020005000Rainfall Intensity in Inches per
Hour12.0012.0012.00Depth of Water above the Weir's Lower Edge in
Inches (1,2)3.003.003.00Number of Weirs111ResultsCalculated Area
for Drainage (ATotal)150030007500Required Weir or Scupper Width in
Inches3366164Required Weir or Scupper Width in Feet3614
Q-CFS = 3.33 (L - 0.2*(H/12)) * (H/12)^1.5Q-GPM = Q-CFS * 7.4805
(CF/GAL) * 60 (Seconds/Min)
Weir Discharge Capacity CalculatorEnter Input ConditionsRun
'A'Run 'B'Run 'C'Length (width) of Weir or Scupper in Feet000Depth
of Water above the Weir's Lower Edge in Inches (1,2)000ResultsFlow
at Input Conditions in Cubic Feet per Second (CFS)0.000.000.00Flow
at Input Conditions in Gallons per Minute (GPM)000
Flow Rate when surface area in square feet and rainfall
intensity in inches per hour are known
Q-CFS = (A * (I / 12)) / 60 / 60Q-GPM = Q-CFS * 7.4805 (SF/GAL)
* 60 (Seconds/Min)
Rainfall Flow Rate CalculatorEnter Input ConditionsRun 'A'Run
'B'Run 'C'Roof Area in Square Feet (SF)000Rainfall Intensity in
Inches per Hour0.000.000.00ResultsFlow at Input Conditions in Cubic
Feet per Second (CFS)0.000.000.00Flow at Input Conditions in
Gallons per Minute (GPM)000
1) Allowable depth as determined by structural systems' water
load capacity2) The depth must exclude from the rim elevation of
the roof drain to the bottom of the Weir
Rectangular Weir TabularRevision 008; 2013-Apr-22Weir Discharge
Rates in Cubic Feet per Second at Listed Width and Water Depth
4 Inches6 Inches12 Inches 18 Inches24 Inches3 Feet5 Feet8 Feet16
Feet461218243660961921 Inch10.030.040.080.120.160.240.400.641.281.5
Inches1.50.050.070.140.220.290.440.731.172.352
Inches20.070.110.220.330.450.671.131.813.622.5
Inches2.50.090.150.300.460.620.941.572.525.053
Inches30.120.190.400.600.811.232.063.316.643.5
Inches3.50.140.230.490.761.021.542.594.178.364
Inches40.170.280.600.921.241.883.165.0810.215
Inches50.220.370.821.271.722.614.407.0914.266
Inches60.270.471.061.652.243.415.779.3018.72
Weir Discharge Rates in Gallons per Minute at Listed Width and
Water Depth
4 Inches6 Inches12 Inches 18 Inches24 Inches3 Feet5 Feet8 Feet16
Feet461218243660961921 Inch111173553711071792875751.5
Inches1.5203164971301973295271,0552
Inches23147981492003025058101,6242.5
Inches2.541651362072784207051,1312,2683
Inches353841772713645519251,4852,9803.5
Inches3.5651042223394576931,1631,8703,7534
Inches4771252684125568441,4192,2824,5835
Inches51001673685697701,1721,9763,1826,3986
Inches61232114767401,0041,5322,5894,1758,402
Do Not Use
Triangular Notch Weir TabularRevision 008; 2013-Apr-22Weir
Discharge Rates in Cubic Feet per Second at Listed Width and Water
Depth
4 Inches6 Inches12 Inches 18 Inches24 Inches3 Feet5 Feet8 Feet16
Feet461218243660961921 Inch10.010.010.030.040.060.090.150.230.471.5
Inches1.50.020.030.050.080.110.160.270.430.862
Inches20.030.040.080.120.170.250.410.661.332.5
Inches2.50.040.060.120.170.230.350.580.931.863
Inches30.050.080.150.230.300.460.761.222.443.5
Inches3.50.060.100.190.290.380.580.961.543.074
Inches40.080.120.230.350.470.701.171.883.765
Inches50.110.160.330.490.660.981.642.625.256
Inches60.140.220.430.650.861.292.163.456.90
Weir Discharge Rates in Gallons per Minute at Listed Width and
Water Depth
4 Inches6 Inches12 Inches 18 Inches24 Inches3 Feet5 Feet8 Feet16
Feet461218243660961921 Inch14713202640661052111.5
Inches1.5812243648731211943872 Inches212193756751121862985962.5
Inches2.5172652781041562604168333
Inches323346810313720534254710953.5
Inches3.529438612917225943169013804
Inches4355310515821131652784316865
Inches54974147221294442736117823566
Inches6659719429038758196815493097
Do Not Use
Square Edged NozzleRevision 008; 2013-Apr-22
Hydraulic HeadPartial flow through a round orifice in a plate
(GPM, Diameter)3 Inches4 Inches6 Inches8 Inches10 Inches12 Inches16
Inches20 Inches24 Inches0.61346810121620240.5
Inch0.522.0039.1288.02156.48244.50352.08625.92978.001408.311
Inch131.1255.32124.48221.30345.77497.91885.181383.101991.661.5
Inches1.538.1167.76152.45271.03423.48609.821084.121693.942439.272
Inches244.0178.24176.04312.96489.00704.161251.841955.992816.633
Inches353.9095.82215.60383.29598.90862.411533.182395.593449.654
Inches462.24110.65248.96442.59691.55995.831770.362766.193983.325
Inches569.59123.71278.34494.83773.171113.371979.333092.704453.486
Inches676.23135.52304.91542.06846.971219.642168.243387.884878.557
Inches782.33146.37329.34585.49914.831317.362341.973659.335269.43
Hydraulic HeadFull flow through a round orifice in a plate (GPM,
Diameter)3 Inches4 Inches6 Inches8 Inches10 Inches12 Inches16
Inches20 Inches24 Inches0.82346810121620240.5
Inch0.529.5852.59118.32210.35328.67473.29841.401314.681893.141
Inch141.8374.37167.33297.48464.81669.331189.921859.242677.311.5
Inches1.551.2391.08204.94364.34569.27819.761457.342277.103279.022
Inches259.16105.17236.64420.70657.34946.571682.802629.373786.293
Inches372.46128.81289.83515.25805.081159.312060.993220.304637.244
Inches483.67148.74334.66594.96929.621338.662379.833718.495354.625
Inches593.54166.30374.17665.181039.351496.662660.734157.395986.656
Inches6102.47182.17409.88728.671138.551639.512914.694554.206558.047
Inches7110.68196.76442.72787.061229.771770.873148.224919.107083.50
Do Not Use
TABLE 1106.2 - MODIFIEDSIZE OF VERTICAL CONDUCTORS AND
LEADERS
Size of LeaderTable 1106.2 Equivalent GPMRainfall rate (inches
per hour)1234567891011122 Inches28803030303030303030303030303
Inches88009191919191919191919191914
Inches184001911911911911911911911911911911911915
Inches346003593593593593593593593593593593593596
Inches540005615615615615615615615615615615615618
Inches1160001,2051,2051,2051,2051,2051,2051,2051,2051,2051,2051,2051,205
TABLE 1106.2SIZE OF VERTICAL CONDUCTORS AND LEADERS
Size of LeaderHORIZONTALLY PROJECTED ROOF AREA (square
feet)Rainfall rate (inches per hour)1234567891011122
Inches2880288014409607205764804113603202882622403
Inches8800880044002933220017601467125711009788808007334
Inches1840018400920061334600368030672629230020441840167315335
Inches346003460017300115338650692057674943432538443460314528836
Inches54000540002700018000135001080090007714675060005400490945008
Inches116000116000580003866729000232001933316571145001288911600105459667
ChangelogDateRevisionNumberBy:Description2012-Nov-074MMR1) First
Release with Changelog2) Revised default Gutter H/W ratio to
1.6183) Revised print layout for Square Edged Nozzle table
2012-Nov-135MMR1) Update filename to 213nnn
series2012-Nov-276MMR1) Added "Adjacent Wall Area" input to include
1/2 wall area in subsequent calculations for gutters, square weirs,
and trangular weirs.2) Added a lookup table based on SMACNA
downspout sizing guidelines.3) Using lookup table recommend a
downspout size taking into account gutter size.4) Flag poor size
choices (number of downspouts and aspect ratio) with a
warning.2012-Dec-107MMR/JC1) Added notes on gutter worksheet to
refer user to SMACNA for construction details.2013-Apr-228MMR1)
Degrade gracefully when downspout count is zero'd rather than throw
Div#0 exception.2) Corrected downspout lookup table error where
DS's 3" dia or less returned maximum flow value instead of area.3)
Revise the recommended DS width max aspect ratio to 2 from 1.6184)
Replaced excel default rounding with ceiling function to use next
largest integer size.5) Added a MAX function to make minimum gutter
width 3"
