Introduction to Water Pipe Sizing

Transcription

1 ONTARIO PLUMBING INSPECTORS ASSOCIATION INC. In the public service since 1920 Introduction to Understanding the Many Methods to Size Water Pipe Presented by: Rainier Bratsch-Blundel, CPSI Plumbing Professor George Brown College OPIA Education and Training 1

2 Where to start. ASPE Data Books 2006 Building Code National Plumbing Code of Canada OPIA Education and Training 2

3 What is found in the ASPE Data Books? 1. A list of empirical formulae for piping friction losses including; The Hazen-Williams Formula city mains and fire mains The Darcy-Weisbach Formula plumbing and process piping friction factor is determine by the Colebrook equation OPIA Education and Training 3

4 What is found in the ASPE Data Books? 2. A method formula for probability of use. Uses a series of tables assigning Water Size Fixture Units to the most common found fixtures in a plumbing system. This is the method found in the Body of the Codes and Appendices of the National Plumbing Code of Canada and Ontario Plumbing Code and Guide. OPIA Education and Training 4

5 Where to look in the Building Code? Design, Fabrication and Installation (1) Potable water systems shall be designed, fabricated and installed in accordance with good engineering practice, such as that described in the ASHRAE Guide and Data Books, the ASHRAE Handbooks and ASPE Data Books. (ASHRAE: American Society of Heating, Refrigerating and Air- Conditioning Engineers, last update 1972), (ASPE: American Society of Plumbing Engineers, updated 2005) OPIA Education and Training 5

6 More from the Building Code? Design Introduction to (1) Except as permitted in Sentences (2) and (3), the size of every pipe in a water distribution system that supplies water to a fixture or device and the flow pressures at the supply openings shall be designed to provide peak demand flow in conformance to Table (2) A tail piece or connector not more than 750 mm long and not less than ¼ in. inside diameter may be used to supply water to a fixture or device. Cont. OPIA Education and Training 6

7 More from the Building Code? Design (cont.) Introduction to (3) A water distribution system that serves not more than a single dwelling unit does not need to conform to Column 3 of Table (4) No water system between the point of connection with the water service pipe or the water meter and the first branch that supplies a water heater, shall be less than ¾ in. size. (5) Every pipe that supplies a fixture shall have a capacity that will produce a flow in the fixture that will flush the fixture and keep it in a sanitary condition. OPIA Education and Training 7

8 Where to look in the Building Code? Hydraulic Load (1) Except as provided in Sentence (3), the hydraulic load of a fixture or device that is listed in Table shall be the number of fixture units given in the Table. (3) Where fixtures are supplied with both hot and cold water, the hydraulic loads for maximum separate demands shall be 75% of the hydraulic load of the fixture units given in Tables and when using a detailed engineering design method. OPIA Education and Training 8

9 T T OPIA Education and Training 9

10 What's in the Appendix of the Building Code? The following may be used as an alternative in determining the size of each section of the water system. This is based on proven design methods found in the Appendix of the National Plumbing Code of Canada. To determine the size of each section of the water supply and distribution systems, use Table A (1), which incorporates the requirements of Sentence (3) for sizing the Water Service Entering the Building. OPIA Education and Training 10

11 STEP 1: Determining conditions Introduction to On a proposed water piping installation sized pursuant to Table A (1), the following conditions need to be determined: i. the total number of "Water Supply Fixture Units" as determined from Tables and for the fixtures to be installed, ii. the developed length of the pipe from the property line to the most remote outlet, or if the pressure at the property line or meter is unknown, the developed length from the public water main to the most remote outlet, OPIA Education and Training 11

12 STEP 1: Determining conditions Introduction to On a proposed water piping installation sized pursuant to Table A (1), the following conditions need to be determined: i. the total number of "Water Supply Fixture Units" as determined from Tables and for the fixtures to be installed, ii. the developed length of the pipe from the property line to the most remote outlet, or if the pressure at the property line or meter is unknown, the developed length from the public water main to the most remote outlet, OPIA Education and Training 12

13 STEP 1: Determining conditions (cont.) iii. the difference in elevation between the water piping at the property line or other source of supply and the highest fixture or outlet, iv. the pressure in the public water main or other source of supply at the locality where the installation is to be made (this pressure may need to be reduced so that the pressure in the water distribution system does not exceed 550 kpa); and, OPIA Education and Training 13

14 STEP 1: Determining conditions (cont.) v. finally, in localities where there is a wide fluctuation of pressure in the main throughout the day, determine the minimum pressure available, which will be used as a basis for this design. OPIA Education and Training 14

15 STEP 2: Water Service Pipe Introduction to i. Beginning with the available pressure at the property line, public water main or other souce of supply, and subtracting 10 kpa for each metre of difference in elevation between such source of supply and the highest water outlet in the building or on the premises, use the "Pressure Range" group in Table A (1) within which the adjusted pressure falls. OPIA Education and Training 15

16 STEP 2: Water Service Pipe Introduction to ii. Select the "Length Column" that is equal to or longer than the required length of service pipe. Follow down the column to a "Water Supply Fixture Unit" equal to or greater than the total number of units required by the installation. Having located the proper unit value for the required length, locate the size of the water service in the left-hand column. OPIA Education and Training 16

17 STEP 2: Table A (1) 200kPa to 310kPa OPIA Education and Training 17

18 STEP 2: Table A (1) 311kPa to 413kPa OPIA Education and Training 18

19 STEP 2: Table A (1) Over 413kPa OPIA Education and Training 19

20 STEP 3: Cold Water Piping Introduction to Starting at the most remote outlet on the cold water piping and working back toward the water service or meter, using the total developed length of pipe, calculate the pipe size for the system using the total "Water Supply Fixture Unit" values given in Tables and and adding the unit demand of the hot water inlet at the point where it occurs. The final size of the cold water service need not be larger than the size required by Table A (1) for the water service. OPIA Education and Training 20

21 STEP 4: Hot Water Piping Introduction to Starting at the most remote outlet on the hot water piping and working back toward the service water heater, calculate the pipe sizing for the system from the "Length Column" selected in Table A (1) using the "Water Supply Fixture Unit" valves given in Table and OPIA Education and Training 21

22 Example OBC: Cl. W. WC Lav Bath Introduction to DW KS SHR Lav WC Hose Bibb WC Bath Lav Hose Bibb KS Cl. W. HWT Bath Lav WC DW OPIA Education and Training 22

23 T T OPIA Education and Training 23

24 (i) the total number of "Water Supply Fixture Units" FIXTURE % W.S.F.U FIXTURES COLD W.S.F.U. HOT W.C. 3 NA LAV BATH SHR K.S D.W. 3 NA CL.W H.B. 4 NA TOTAL COLD 59 SUB-TOTAL OPIA Education and Training 24

25 (ii) (iv) Determining Conditions Introduction to (ii) - (iv) DETERMINE CONDITIONS DEVELOPED LENGTH 23 m PRESSURE AT SOURCE 550 kpa CHANGE IN ELEVATION 9 m MINUS 10kPa PER metre - 90 kpa PRESSURE RANGE 460 kpa OPIA Education and Training 25

26 STEP 2: Table A (1) Over 413kPa OPIA Education and Training 26

27 STEP 2: Water Service Pipe Introduction to SIZING as per A (1) WATER SERVICE 1 (1 1/4 ) WATER DISTRIBUTION PIPING 1 1/4 108 WSFU 1 55 WSFU 3/4 24 WSFU 7 WSFU OPIA Education and Training 27

28 Example OBC: STEP 3: Cold Water Piping 1" 1 1/4 Cl. W. WC Hose Bibb Lav Bath 1 1/4" 1/2 Introduction to DW 1 1/4" KS 1" SHR KS Cl. W. HWT Bath Lav WC DW Lav WC 1/2 Hose Bibb Bath Lav OPIA Education and Training 28 WC

29 Example OBC: STEP 4: Hot Water Piping Cl. W WC Lav Bath Introduction to DW KS SHR Lav WC Hose Bibb WC Bath Lav Hose Bibb KS Cl. W. HWT Bath Lav WC DW OPIA Education and Training 29

30 Changes to the National Plumbing Code (NPC); Design (1) Every water distribution system shall be designed to provide peak demand flow when the flow pressures at the supply openings conform to Table the plumbing supply fitting manufacturer s specifications. OPIA Education and Training 30

31 Changes to the National Plumbing Code; Size (5) Where both hot and cold water is supplied to fixtures in residential buildings containing one or two dwelling units or row houses with separate water service pipes, the water system may be sized in accordance with Table where: (a) the hydraulic loads for maximum separate demands on water distribution system piping are not less than 100% of the hydraulic load of the fixture units given in Table or for private use, (b) the minimum water pressure at the entry to the building is 200 kpa, and (c) the total maximum length of water system is 90 m. OPIA Education and Training 31

32 Addition of Table to the NPC; OPIA Education and Training 32

33 Table for Buildings Containing One or Two Dwelling Units or Row Houses with Separate Water Service Pipes Forming Part of Sentence (5) Size of Water Pipe, inches Water Velocity, m/s (1) Hydraulic Load, fixture units ½ ¾ ¼ Note to Table : (1) Table is not intended to limit water velocities that are specified in Sentence (1) OPIA Education and Training 33

34 Changes to the National Plumbing Code; Velocity (1) The maximum permitted flow velocities shall be those recommended by the pipe and fitting manufacturer. OPIA Education and Training 34

35 Example NPC: Cl. W. WC Lav Bath Introduction to DW KS SHR Lav WC Hose Bibb WC Bath Lav Hose Bibb KS Cl. W. HWT Bath Lav WC DW OPIA Education and Training 35

36 (i) the total number of "Water Supply Fixture Units" FIXTURE H/C FIXTURES H/C TOTAL COLD W.S.F.U. W.C LAV BATH SHR K.S HOT D.W CL.W H.B TOTAL COLD 30.6 SUB-TOTAL OPIA Education and Training 36

37 Example NPC: Cold Water Piping Cl. W. WC Lav Bath 1" Introduction to DW 1 " KS SHR Lav WC 1/2 Hose Bibb WC Bath Lav 1" 1 Hose Bibb 1/2 KS Cl. W. HWT Bath Lav WC DW OPIA Education and Training 37

38 Example NPC: Hot Water Piping Cl. W WC Lav Bath Introduction to DW KS SHR Lav WC Hose Bibb WC Bath Lav Hose Bibb KS Cl. W. HWT Bath Lav WC DW OPIA Education and Training 38

39 QUESTIONS? seminar_backflow.aspx proposed_changes.shtml OPIA Education and Training 39

40 ONTARIO PLUMBING INSPECTORS ASSOCIATION INC. In the public service since 1920 Introduction to Understanding the Many Methods to Size Water Pipe Presented by: Rainier Bratsch-Blundel, CPSI Plumbing Professor George Brown College OPIA Education and Training 40