Plumbing Design Criteria

3.00

DESIGN CRITERIA

Hunter Soil and Waste Systems

3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17

Design Criteria Hunter Plumbers Bits Depths of water seal in traps Pipework and sizing Branch Connections to Stacks Ventilation of Discharge Stack Air Admittance Valve Air Admittance Valve BBA Specification Ventilation of Soil & Waste Stub Stack Boss Connections Waste Manifold WC Connections Drain Connector Flexible Waste Adaptor Access Gullies Overflow Discharge

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Design Criteria

3.01 DESIGN CRITERIA

All sanitary pipework and drainage installations must satisfy Part H1 of the approved documents to the England, Wales and Northern Ireland Building Regulations 1991 and 1994 respectively. Also the Building Standards (Scotland) amendment regulations 1990. These requirements can also be met by following the relevant recommendations of BS EN 12056:2000 which contains information on performance rates and discharge levels from sanitary appliance including, recommendations for design, testing, installation, and maintenance for all above ground non-pressure pipework systems. Regular consultation is essential between plumbing engineers and architects through every stage of design. This helps to ensure the positions of sanitary appliances and ducts permitting efficient pipework installation at minimum cost. In addition, a well designed and installed sanitary waste system will satisfy the following basic criteria: • Be of adequate capacity, with suitable pipe sizes and gradients, to carry foul water to a suitable drainage system for disposal. • Allow minimal risk of blockage or leakage and have the provision for inspection and cleaning. • Stop foul air from entering the building during normal working conditions (through use of water seal traps). • Have ventilation to preserve water seal integrity. • Be securely fixed to cope with structure and environmental conditions and changes.

3.02 HUNTER PLUMBERS BITS TRAPS

To comply with Approved Document H of the Building Regulations all points of discharge into the drainage system should be fitted with a water seal trap to prevent foul air from the system entering the building. Plus, the waste pipe diameter and gradient must be selected to maintain a minimum of 25mm water seal in the trap after an appliance has been used. However, Hunter manufacture a range of resealing traps and anti-siphon units that may be used where the integrity of the water seal cannot be guaranteed. Hunter's traps can be dismantled for inspection and maintenance, which should be done on a regular basis to ensure the trap functions correctly. 3.03 DEPTHS OF WATER SEAL IN TRAPS

BS EN 12056 - 2: 2000 requires that traps that discharge to a soil stack have a 75mm water seal, however, 50mm water seal traps can be fitted to baths; shower trays and basins without plugs fitted with spray taps. 38mm water seal traps can only be used on ground floor flat bottomed appliances that * discharge to a back inlet gully trap. Traps with outlet diameters greater than 50mm, should have a minimum water seal depth of 50mm. Appliance

Trap outlet size (mm) Wash Hand Basin 32 Bidet 32 Bar Well 32 Drinking Fountain 32 Sink 40 *Kitchen Cleaners Sink 40 * Waste Disposal (Domestic) 40 Bowl Urinal 40 Sanitary Towel Macerator 40 Dishwasher (Domestic) 40 Washing Machine 40 Bath 40 * 40 *Shower Tray Waste Disposal (Industrial) 50 Urinal Stall (1-7 persons) 65 Water Closet 75-100

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Design Criteria

3.04 PIPEWORK AND SIZING SIZES OF BRANCH PIPES Since June 2001 British Standard, Euro Norm BS EN 12056: 2000 Gravity Drainage Systems Inside Buildings has replaced BS EN12056-2:2000 as the standard governing the installation of above ground pipework. The United Kingdom’s sanitary pipework system of single stack layouts requiring swept entry on equal branch junctions and our method of designing ranch waste pipes running full are included in the new standard, listed as System III and in the National Annex of part two. The national annex will allow the UK to continue to design and install sanitary pipework with only some minor alterations from our previous standard. Amendments to Par H of the Building Regulations that come into force in April 2002 will bring it in line with the new British Standards. Pipes serving a single appliance should have the same diameter as the appliance trap (see table on previous page). However by increasing the pipe diameter the length of the unventilated waste can be lengthened. Where the larger branch pipe is used the trap diameter is not increased but 50mm of the smaller pipe is used before increasing the pipe size. To prevent the need for additional ventilation of the pipework the pipe lengths are restricted as shown in the following DESIGN OF BRANCH DISCHARGE PIPES chart, the UNVENTILATED BRANCH CONNECTION TO STACK diagram, and the DESIGN CURVE FOR BASIN WASTE PIPES diagram. Further details can be found in Approved Document H and BS EN 12056-2: 2000. DISCHARGE UNIT METHOD A numerical value is assigned to each sanitary appliance to express its load producing property. he unit values of all sanitary appliances discharging into the discharge stack and internal drainage are calculated to find the pipe diameter by the method given in the British Standard.

DESIGN OF BRANCH DISCHARGE PIPES Unventilated branches highlighted in Grey (Bold) , branches requiring ventilation marked in Black Appliance

No. of appliances

Trap size mm and trap type

Branch dia.

Max. length of branch in m

Max. No. of bends

Action to be guarded against

Trap type

Branch Gradient in mm/m

Wash Basin or Bidet

1 1 1

32P 32P 32P

32 40 32

1.7 3.0 3.0

A 2A 2A

EX SS EX SS EX SS

22 18-45 18min

Up to 4 5

32P

50

4.0

NONE

EX IS SS

TB TB R AV ASU TB

32P

50

7.0

A

EX IS SS

18-45

10

32P

50

10.0

A NL

EX IS SS

18-45

1

40P or S

40

A NL

EX SS

1

40P

40

3.0 L 3.0

TB R AV ASU TB AV ASU TB

A NL

EX

T

18-45

1 2-8 8+ 1 NL 1

100P or S 100P or S 100P or S 40P or S 40P or S 60P or S

110 110 110 40 50 60

6.0LL 15.0 NL 3 SAP SAP 3 SAP

A NL 2A A NL A NL A A NL

EX EX IS EX

AAV T T T

18min 9-90 min9 18-90 18-90 18-90

1

50P or S

50

3 SAP

A

EX

T

18-90

Shower, Bath, Sink Domestic Washing Machine or Dishwasher WC

Bowl Urinal Slab Urinal for Max 7 People Trough Urinal

NOTES: A: Only use swept bends or branches AAV: Air admittance Valve EX: Excessive deposits IS: Induced siphonage LL: Longer branches are allowed in BS EN 12056-2:2000 SAP: As short as practicable to limit excessive deposits

18-45

18-90

ASU: Ant-siphon unit AV: Anti-vacuum trap B: Bottle trap L: Longer branches are allowed which may result in noisier discharge and blockages NL: No limit R: Resealing trap SS: Self-siphonage T: Tubular trap

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Design Criteria

3.04 PIPEWORK AND SIZING CONT-

UNVENTED BRANCH CONNECTIONS TO STACK

3m max for 40 mm pipe *4 m max for 50 mm pipe

*3 m max for 40 mm pipe

Slope between 18 to 90 mm/m

Slope (see graph below)

Sink 3m max for 40 mm pipe *4 m max for 50 mm pipe Slope between 18 to 90mm/m

1.7 m max for 32 mm pipe

6 m max for single WC

Washbasin

Slope 18 mm/m min WC

Bath

Note: *Where the larger branch pipe sizes are used the diameter of the trap is not increased but the tail of the trap should be lengthened by 50 mm before increasing the diameter.

BRANCH VENTILATION PIPES Vent pipe connection above spillover level Spillover 750 mm max level

Discharge pipe

DESIGN CURVE FOR 32 mm UNVENTED WASH BASIN WASTE PIPES

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Design Criteria

3.05 BRANCH CONNECTIONS TO STACKS

3.06 VENTILATION OF DISCHARGE STACK

SINGLE STACK SYSTEM (SYSTEM III) Building regulations and code of practice requirements 1.The distance between the lowest branch connection to the discharge stack and the invert of the bend at the foot of the stack should not be less than the table below: LOW RISE

up to 3 storeys

–

450 mm

MULTI-STOREY

up to 5 storeys Over 5 storeys

– –

Over 20 storeys

–

750 mm Ground floor connections should discharge direct to drain or into their own stack.

Ventilation of the discharge stack is required to prevent water seals in traps from being lost by pressure which can develop in the system, allowing foul air to escape. Separate ventilation of branch pipes will not be needed if the length and slope of the branch does not exceed those in the diagram below. In cases where these figures are exceeded, the branch pipe should be ventilated by a branch ventilating pipe or by a Hunter anti-siphon unit.

Ground and first floor connections should discharge into their own stack.

2.A branch pipe should not discharge into a stack in a way which could cause crossflow into any other branch pipe. The Hunter waste manifold has been developed precisely to facilitate multi point connections to the stack, eradicating the danger of crossflow even within the danger zones marked by A and B on the soil stack below. BRANCH CONNECTIONS TO STACKS

3m max for 40 mm pipe *4 m max for 50 mm pipe

1.7 m max for 32 mm pipe *3 m max for 40 mm pipe

Slope between 18 to 90 mm/m

Slope (see graph below)

Sink 3m max for 40 mm pipe *4 m max for 50 mm pipe Slope between 18 to 90mm/m

6 m max for single WC

Washbasin

Slope 18 mm/m min WC

Bath

Note: *Where the larger branch pipe sizes are used the diameter of the trap is not increased but the tail of the trap should be lengthened by 50 mm before increasing the diameter.

A

BRANCH VENTILATION PIPES

WC

Lowest connection

50 mm parallel junction

B 450 mm min

mm 50

Offset

200 mm

Danger zone

Drain invert Minimum Radius 200mm Key A small similar sized connections not exceeding 65 mm and directly opposite should be offset by 110mm on a 100 mm diameter stack 250 mm on a 150 mm diameter stack. B Angled connection or 50 mm diameter parallel junction where a waste branch directly opposite a WC would enter the stack within 200 mm below the WC connection centreline. For further information see section 3.11

Vent pipe connection above spillover level Spillover 750 mm max level

Discharge pipe

DESIGN CURVE FOR 32mm UNVENTED WASH BASIN WASTE PIPES

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Design Criteria

3.07 AIR ADMITTANCE VALVE

AIR ADMITTANCE VALVES Air admittance valves are designed to decrease the number of suspended floor and roof penetrations required to accommodate soil and ventilating stacks without reducing the effectiveness or performance of the system. They also reduce the quantity of components required to complete a system. Figure 1 Relief Valve Cover

Moving seal carrier

Star-lok washer

Spring retainer

Stainless steel spring

Seal Screw cap Outer body

any soil stack. It should be situated in a non-habitable area of the building, e.g. the roof space, where it will be easily accessible and there is reduced risk of freezing. Care must be taken to prevent contamination of moving parts. In the event of accidental damage or vandalism once installed, the cover can be unscrewed and the damaged part (s) replaced. The underground drain which serves a group of stacks to which air admittance valves are fitted may require additional ventilation. This will minimise the effects of excessive back pressure if blockage should occur in a drain. In determining the requirement for additional ventilation to the underground drainage system the following rules can be used for general guidance (see figure 9). I. Up to and including four domestic dwellings up to 3 storeys high, additional drain ventilation is not necessary.

Inner body Positive pressure (closed position)

110mm soil pipe

Diaphragm seal

2.Where an underground drain serves more than four such dwellings which have soil systems fitted with an air admittance valve, the drain must be vented as follows: a.In the case of five to ten such dwellings, additional conventional ventilation must be provided at the head of the underground drainage system.

Negative pressure (open position)

The valve contains a diaphragm which under light spring pressure is normally held closed, containing foul air within the system. When there is a discharge from an appliance, a negative air pressure is produced in the system. This pressure causes the diaphragm in the valve to lift from its seat, allowing air to be drawn into the system: this intake and the rapid equalisation of air pressure prevents foul air escaping and prevents the water seals in traps from being broken.

b.In the case of eleven to twenty such dwellings, additional conventional ventilation must be provided at the head and midpoint of the underground drainage system. Vent Cowl

Soil stack without Hunter Relief Valve and Hunter Anti-Siphon Valve Weathering Slate

ROOF SPACE

ROOF TRUSS

Polystyrene tops can be fitted over the valve cover after installation, providing insulation for the valve in use. The valve incorporates a socket for solvent welding to 110mm PVCu pipe to BS EN1329:2000. It can be fitted to sanitary pipe work systems of buildings up to 5 storeys high. Air admittance valves must be installed in a vertical position above the flood level of the highest appliance connected to

Wash hand basin 32mm pipe Bath 40mm pipe

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Design Criteria

3.07 AIR ADMITTANCE VALVE CONTSoil stack with Hunter Relief Valve and Hunter Anti-Siphon Valve

Vent Cowl not required

Requirement: H1(1)

Foul water drainage

Comment:

The products will: (1) provide adequate ventilation to prevent the loss of water seals in trapped appliances. See sections 6.1, 7.1 to 7.3, 7.8 to 7.10, 8.1 and 8.2 of this Certificate. (2) prevent foul air from entering the building. See section 8.2 of this Certificate. (3) enable access to the sanitary pipework for cleaning blockages. See section 7.1 of this Certificate. (4) contribute to the ventilation of underground drains. See sections 7.2 and 7.3 of this Certificate.

Weathering Slate not required

ROOF SPACE

Bends not required Alternative positions for Hunter Relief Valve

ROOF TRUSS

110mm Soil pipe not required

Requirement: Regulation 7 Materials and workmanship

The products are acceptable.

Comment: Hunter Relief Valve

Wash hand basin

Hunter Anti-Siphon Unit Bath

2 The Building Standards (Scotland) Regulations 1990 (as amended) In the opinion of the BBA, Hunter Air Admittance Valve and Hunter Anti-Siphon Unit, if used in accordance with the provisions of this Certificate, will satisfy the various Regulations as listed below.

32mm reducer 40mm tee

40mm pipe

3.08 AIR ADMITTANCE BBA SPECIFICATION

Regulation:

10

Fitness of materials

Standards:

B2.1.B2.2

Selection and use of materials, components and other manufactured products The products are acceptable.

Comment: Regulation:

24

Drainage and sanitary facilities

PRODUCT

Standard:

M2.2

Drainage system

THIS CERTIFICATE REPLACES CERTIFICATE No 83/1066 AND RELATES TO THE HUNTER AIR ADMITTANCE VALVE AND HUNTER ANTI-SIPHON UNIT, FOR ABOVE-GROUND DRAINAGE SYSTEMS.

Comment:

• The products are for use within buildings in above ground drainage systems designed in accordance with this Certificate. • The valve and unit provide a means of ventilation to the drainage system to prevent the loss of water seals in traps and consequent release of foul air into the building. • The drainage systems and the installation and use of the products must be in accordance with the conditions set out in the Design Data and installation parts of this Certificate. 1 The Building Regulations 1991 (as amended) (England and Wales) 2002 Edition effective April 2002 The Secretary of State has agreed with the British Board of Agrément the requirements of the Building Regulations to which air admittance valves can contribute in achieving compliance. In the opinion of the BBA, Hunter Air Admittance Valve and Hunter AntiSiphon Unit, used in accordance with the provisions of this Certificate, will contribute to meeting the relevant requirements.

The products can meet the relevant requirements of this Standard. See sections 6.1, 7.1 to 7.3, 7.8, 7.9, 8.1 and 8.2 of this Certificate.

3 The Building Regulations (Northern Ireland) 1994 (as amended) In the opinion of the BBA, Hunter Air Admittance Valve and Hunter Anti-Siphon Unit, if used in accordance with the provisions of this Certificate, will satisfy the various Building Regulations as listed below. Regulation:

B2

Regulation:

Fitness of materials and workmanship The products are acceptable.

Comment: N2

Comment:

Drainage Systems The valves provide adequate ventilation to prevent the destruction of the water seals in traps. See sections 6.1, 7.1 to 7.3, 7.8, 7.9, 8.1 and 8.2 of this Certificate.

TECHNICAL SPECIFICATION 4 Description 4.1 Hunters Air Admittance Valve comprises a two-part acrylonitrilebutadiene-styrene (ABS) inner body, seal carrier, spring retainer and cover, an unplasticized polyvinyl chloride (PVCu) outer body and screw cap, a neoprene diaphragm seal to BS 2752 :1990, a nitrile seal washer to BS EN681:1996, a stainless steel spring and a stainless steel Star-Lok washer (see Figure 1). 4.2 the Hunter Anti-Siphon Unit comprises an ABS seal carrier, cover, body and screw cap, a nitrile diaphragm and washer to BS EN681:1996, and a stainless steel Star-Lok washer (see Figure 2). 4.3 The Air Admittance Valve incorporates a socket for solvent welding to 110mm PVCu soil pipe to BS EN1329:2000

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Design Criteria

4.4 With the use or an appropriate adaptor to BS EN1329:2000 the Hunter Air Admittance Valve can be connected to other materials (eg cast iron). 4.5 The Anti-Siphon Units are available in five spigot outlet sizes to connect to either 32 mm or 40 mm waste systems to BS EN1566/BS EN1566:2000 or 32 mm, 40 mm and 50 mm metric waste pipe systems. 4.6 The ABS and PVCu parts are manufactured by injection moulding. 4.7 The diaphragm seals, sea washer, stainless steel Star-Lok washers and springs are bought in. 4.8 Continuous quality control is carried out during manufacture and assembly of the valves and units, including visual checks, checks on dimensional accuracy, airtightness and stress relief. At hourly intervals the ABS components of the Hunter Air Admittance Valve are assembled and checked for freedom of rotation and flatness. The raw materials and bought-in components are also subject to quality control checks.

Figure 2 Hunter Anti-Siphon Unit

All dimensions in millimetres

7 Drainage system design 7.1 The following above-ground drainage systems, designed in accordance with BS EN 12056-2: 2000 and incorporating Hunter valves and units, have been assessed as satisfactory: (a) Domestic Buildings (eg bungalows, houses, multi-storey flats, halls of residence) - satisfactory drainage systems incorporating the valves and units are shown in Figures 3, 4 and 5. (b) Non-domestic buildings (eg offices, factories, schools and other types of public buildings) - satisfactory drainage systems incorporating the valves and units are shown in Figures 6 and 7. Note: In each case referred to, different combinations of sanitary fittings are permissible, provided the siphonage effects occurring within the systems are not made more onerous. Where individual appliances are liable to self-siphonage (eg S-trap connections) venting with an additional Hunter Anti-Siphon Unit may be required.

Figure 3 Typical domestic installation

61

Hunter Air Admittance Valve fitted above flood level

Seal washer

22

Vent ducts

36

6.4 The valve and unit are for use in association with each other or separately.

Spigot to socket fitting

Diaphragm seal

Sink

P-trap

Hunter Anti-Siphon Unit

Wash basin

32mm pipe

Bath

Star-lok washer

P-trap

Variable spigot size

5 Delivery and site handling 5.1 The manufacturer’s emblem and the BBA identification mark incorporating the number of this Certificate are printed on the cover of each Hunter Air Admittance Valve. 5.2 The valves are individually packed in plastic bags or cardboard boxes and should remain stored upright and so protected until they are required for use. 5.3 The manufacturer’s emblem and the BBA identification mark incorporating the number of this Certificate are printed on the cover of each Hunter Anti-Siphon Unit. 5.4 The units are packed in a plastic bag. Each bag carries a label bearing the BBA identification mark incorporating the number of this Certificate. DESIGN DATA 6 General 6.1 When used in accordance with the provisions of this Certificate in above-ground drainage systems designed in accordance with BS EN 12056-2: 2000, the valves: (a) admit air under conditions of reduced pressure in the discharge pipes and prevent water seals in traps from being drawn (b) prevent the release of foul air from the drainage system, and (c) contribute to the ventilation of the main drain to which the discharge stack incorporating the valve is connected. 6.2 The Hunter Air Admittance Valve is for use on discharge stacks serving up to five storeys. 6.3 The Hunter Anti-Siphon Unit is for use on branch discharge pipes.

110mm soil and vent pipe

40mm pipe

Notes: • The maximum distance of appliance traps from the discharge stack must be in accordance with BS EN12056-2:2000, paragraph 7.2.2 and figures 16, 18, 19 and 20. The separate ventilation shown on the BS figures may be provided by a Hunter Anti-Siphon Unit which must be within 750mm of the appliance trap • The size of the branch discharge pipework and the location of appliances must be designed in accordance with BS EN 12056-2: 2000 7.2 The Air Admittance Valve must be fitted in a vertical position above the flood level of the appliance. being served. 7.3 To contribute to the ventilation of the underground drain and to minimise the effects of excessive back pressures when a drain blockage. occurs, the branch or main drain serving a stack or stacks fitted with Hunter valves and units may require venting at point upstream of the stack connection. For guidance the following should be noted (see Figure 9): (a) For up to and including four dwellings, 1, 2, or 3 storeys in height, additional drain venting is not required. Where a drain serves more than four such dwellings equipped with the valve or unit, the drain should be vented according to the following rule, by either a conventional open-topped ventilation or a discharge stack: 5 to 10 such dwellings - conventional ventilation to be provided at the head of the system. 11 to 20 such dwellings - conventional ventilation to be provided at the mid-point and at the head of the system. (b) For multi-storey domestic dwellings (other than those referred to above) and non-domestic buildings, conventional drain venting should be provided if more than one such building, each equipped with the valves and units, is connected to a common drain which is not itself vented by means of a ventilation stack or a discharge stack not fitted with a valve or unit.

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Design Criteria

Figure 4 Typical layout using Hunter Air Admittance Valve and Hunter Anti-Syphon Unit on a 110mm branch line

Hunter Air Admittance Valve or conventional open stack Hunter Anti-Siphon Unit Wash hand basin 32mm pipe Bath

40mm pipe

Hunter Anti-Siphon Unit

Hunter Anti-Siphon Unit

Wash hand basin

Hunter Air Admittance Valve

Wash hand basin

32mm pipe

32mm pipe

Bath

Bath 40mm pipe

40mm pipe

110mm pipe

110mm pipe

Notes: • Maximum of two groups of appliances per floor. • A group of appliances consists of one wc, one or two wash basin, one sink and one bath (and/or shower) and a washing machine. • The maximum distance of appliance traps from the discharge stack must be in accordance with BS EN 12056-2: 2000. The separate ventilation shown on the BS figures may be provided By Hunter Anti-Siphon Unit which must be within 300 mm of the appliance trap. • The size of the branch discharge pipework and the location of appliances must be designed in accordance with BS EN 12056-2: 2000.

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Design Criteria

Figure 5 Domestic discharge system Hunter Anti-Siphon unit 32mm pipe

Hunter Air Admittance Valve

Wash hand basin

Sink P-trap

Bath

40mm pipe 40mm pipe maximum 5 floors maximum 2 groups of appliances per floor

Hunter Anti-Siphon unit 32mm pipe

Wash hand basin

Sink P-trap

Bath 40mm pipe 40mm pipe

Long radius bend

Notes:

>110mm diameter

• Maximum of two groups of appliances per floor. • A group of appliances consists of one wc, one wash basin, one sink and one Both (and/or shower). • The maximum distance of appliance traps from the discharge stack must be in accordance with BS EN 12056-2: 2000. The separate ventilation shown on the BS figures may be provided by a Hunter Anti-Siphon Unit which must be within 300 mm of the appliance trap. • The size of branch discharge pipework and the location of appliances must be designed in accordance with BS EN 12056-2: 2000.

Figure 6 Commercial and public discharge system 40mm ASU Up to 5 wash basins

Hunter Air Admittance Valve Up to 5 WC connections

P-traps

50mm minimum

Typical P-trap installation

S-traps or P-traps can be used

Maximum 5 floors

Up to 5 wash basins Up to 5 WC connections

S-traps or P-traps can be used

ASU

ASU

ASU

Typical S-trap installation 50mm minimum

110mm pipe

Notes:

160mm pipe

• Valves to be fitted vertically. • If the valve is fitted inside a duct then the duct will require ventilation. • Branch discharge pipes to ranges of appliances must be designed in accordance with BS EN 12056-2: 2000. Where required, branch pipe ventilation may be provided by the Hunter Anti-Siphon Unit.

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Design Criteria

Figure 7 Permitted number of appliances in non-domestic buildings (eg offices, factories, schools and other types of public buildings) Hunter Air Admittance Valve Hunter Anti-Siphon Unit on each storey 2(1)

5(1)

5(3)

2(1)

5(1)

5(3)

2(1)

5(1)

5(3)

2(1)

5(1)

5(3)

2(1)

5(1)

Hunter Air Admittance Valve

110mm dia pipe

110mm dia pipe

(i) 1 to 4 storeys

110mm dia pipe

(ii) 1 to 5 storeys

(iii) 1 to 5 storeys

Maximum 2 or 5 groups of appliances per floor (1 or 3 groups in congested circumstances) Notes: • A group of appliances consists of one wc and one wash basin. • Congested circumstances are where the frequency of use of each appliance is approximately five minutes • Normal use in non-domestic buildings corresponds to frequencies of use of approximately ten minutes. • Hydraulic performance tests carried out in accordance with BS EN 12056-2: 2000, indicate that the installations shown above are acceptable.

Figure 8 Typical installation of the Anti-Siphon Valve Sanitary appliance Hunter Anti-Siphon Unit Solvent weld Tee

Vacuum releases diaphragm - pressure neutralised

Plug of water flowing full bore

Water level retained due to Hunter Anti-Siphon Unit

921⁄ 2˚ tee

Constant 76mm seal

Negative pressure area 300mm max distance centre line of unit to crown of trap Bottle/tubular trap

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Design Criteria

Figure 9 Examples of drain ventilation provisions

Notes: • Access arrangements shown are indicative only and may he varied to suit particular system layouts • The underground drain must be designed in accordance with BS EN 752: 1996 • if the Branch drain is fitted with an intercepting trap before the connection to the main drain/sewer then a conventional open topped ventilation discharge stack must be provided at the nearest point upstream of the intercepting trap

7.4 In installations other than as shown in Figure 9 stacks should not be fitted with the valves when the connecting drain(s) are subject to periodic surcharging or are fitted with intercepting traps. An open-topped discharge stack or ventilating stack should be used in such cases. 7.5 The valve should be installed within the building, preferably in a nonhabitable space, such as a duct or roof, where there is no risk of freezing, and where it is easily accessible but not subject to interference by vandals. 7.6 If the valve is to be installed in, or in close proximity to, a habitable space where noise of operation may cause a nuisance then consideration must be given to the use of a suitable form of sound insulation. 7.7 To prevent self-siphonage, a connection to the Hunter Anti-Siphon Unit is required within 300 mm of the trap (see Figure 8). 7.8 To prevent induced siphonage in a row of wash basins, a Hunter Anti-Siphon Unit should be fitted near the end of the branch remote from the discharge stack (see Figure 6). 7.9 The Anti-Siphon Unit must be fitted in a vertical position above the pipe being ventilated. 7.10 Air admittance valves should not be used when the soil stack provides the only ventilation to septic tanks or cesspools.

8 Effect on water seals 8.1 The valves will admit sufficient quantities of air into the stack when they are subjected to a reduced pressure and thereby prevent loss of the water seals in appliance traps. 8.2 Under conditions of increased pressure in the drainage system, each valve will remain closed, thereby preventing the release of foul air into the building. 8.3 A pressure increase sufficient to raise the level of the water seal or to cause foul air to bubble up through the seal is an indication that a drain blockage has occurred or that the system is being overloaded or otherwise misused. 9 Durability Hunter valves and anti-siphon units are - manufactured from materials conventionally used in drainage systems. Repeated opening and closing will not adversely affect the sealing or operation of the valve. When used in the context of this Certificate the product will not be subject to significant deterioration and will have a life equivalent to that of the drainage system in which it is installed.

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Design Criteria

INSTALLATION 10 Procedure 10.01 Installation must be carried out in accordance with the manufacturer’s instructions for the products.

BS EN1329:2000/BS EN727:1996, EN 1055: 1996 Specification for unplasticized PVC soil and ventilating pipes, fittings and accessories Specification for P.P Waste Systems and Soil and Waste Discharge within the building structure Chlorinated Poly (vinyl chloride (PVC-c) BS EN1451:2000 and BS EN1566:2000, BS EN1566

10.2 The Hunter Air Admittance Valve must be fitted to the top of the discharge stack above the over-spill level of the highest appliance. The 110mm diameter spigot tail valve may be push fitted into ring seal sockets after applying Hunter’s lubricant to the spigot tail, or solvent welded into PVCu sockets. The 110mm socket outlet is for solvent welding to PVCu pipe.

BS EN 12056: 2000 Gravity drainage systems inside buildings

10.3 The Hunter Anti-Siphon Units (code Nos W150 and W151) may be solvent welded into 32mm or 40mm ABS, PVC-c or PVCu waste fittings to BS 5256, BS EN1566:2000, or BS EN 1329:2000, using solvent cement. BS 6209 1982.

14 Conditions

The cementing procedure should follow the instructions on the Hunter solvent cement label. The 32mm, 40mm and 50mm metric waste pipe sizes may be jointed to polypropylene on thermoplastic systems, using the methods described here.

BS 6209 : 1982 Specification for solvent cement for non-pressure thermoplastics pipe systems BS EN 752: 1998 Drain and sewer systems outside buildings

14.1 This Certificate: (a) relates only to the product that is described, installed, used and maintained or set out in this Certificate; (b) is granted only to the company, firm or person identified on the front cover no other company, firm or person may hold or claim any entitlement to this Certificate;

10.4 Care must be taken in making solvent welded joints to prevent contamination of the moving parts.

(c) has to be read, considered and used as a whole document - it may be misleading and will be incomplete to be selective;

11 Maintenance

(d) is copyright of the BBA.

11.1 The Hunter Air Admittance Valve does not normally require maintenance. However, in the event of accidental damage or vandalism the cover can be unscrewed and the damaged component parts or the complete assembly replaced.

14.2 References in this Certificate to any Act of Parliament, Regulation made thereunder, Directive or Regulation of the European Union, Statutory Instrument, Code of Practice, British Standard, manufacturers’ instructions or similar publication shall be construed or references to such publication in the form in which it was current at the date of this Certificate.

11.2 The Hunter Anti-Siphon Unit does not normally require maintenance. However, in the event of misuse, accidental damage or vandalism the cover can be removed and the diaphragm seal cleaned, or the complete assembly replaced if necessary. Technical Investigations

14.3 This Certificate will remain valid for an unlimited period provided that the product and the manufacture and/or fabricating process(es) thereof: (a) are maintained at or above the levels which have been assessed and found to be satisfactory by the BBA;

The following is a summary of the technical investigations carried out on the Hunter Air Admittance Valve and Hunter Anti-Siphon Unit.

(b) continue to be checked by the BBA or its agefits; and

12 Tests

14.4 In granting this Certificate, the BBA makes no representation as to:

Tests were carried out to determine:

(a) the presence of absence of any patent or similar rights subsisting in the product or any other product;

effect of pressure cycling, performance in use an a stack when tested in accordance with BS EN1055:1996, airtightness under normal operating conditions, airtightness when tested to pressures of 40mm and 200mm water gauge, airtightness at low positive pressure, reduced pressure required to open the valve, watertightness under positive pressure, effect on the seal depth of a bottle trap when fitted near an anti-siphon unit with the discharge pipe running full, prevention of loss of trap seals due to induced and self-siphonage, Vicat softening point to BS EN727:1994, tensile strength, Shore hardness of diaphragm seals, dimension, practicability of installation, load test on the spring, corrosion resistance of materials, effects of impact drop test and correct functioning and effect of repeated operation. 13 Other investigations 13.1 The manufacturing process was examined, including the methods adopted for quality control, and details were obtained of the quality and composition of materials used. 13.2 An examination was made of data on induced siphonage. 13.3 A user survey was carried out to evaluate the performance in use. 13.4 No failures of the product have been reported to the BBA. 13.5 An examination was made on airflow capacity. Bibliography BS EN681 Part 1 or 2:1996 Specification for elastomeric seals for joints in pipework and pipelines BS 2752 : 1990(1997) Specification for chloroprene rubber compounds BS 2782 Methods of testing plastics Part 1 Thermal properties Determination of Vicat softening temperature of thermoplastics

(c) are reviewed by the BBA or and when it considers appropriate.

(b) the right of the Certificate holder to market, supply, install or maintain the product; and (c) the nature of individual installations of the product, including methods and workmanship. 14.5 Any recommendations relating to the use or installation of this product which are contained or referred to in this Certificate are the minimum standards required to be met when the product is used. They do not purport in any way to restate the requirements of the Health & Safety at Work Act 1974, or of any other statutory, common law or other duty which may exist at the date of this Certificate or in the future; nor is conformity with such recommendations to be taken as satisfying the requirements of the 1974 Act or of any present or future statutory, common law or other duty of care. In granting this Certificate, the BBA does not accept responsibility to any person or body for any loss or damage, including personal injury, arising as a direct or indirect result of the installation and use of this product. In the opinion of the British Board of Agrément, Hunter Air Admittance Valve and Hunter Anti-Siphon Unit are fit for their intended use provided they are installed, used and maintained as set out in this Certificate. Certificate No 86/1737 is accordingly awarded to Hunter Plastics Ltd. On behalf of the British Board of Agrément Date of Second issue: 24th November 1998 DIRECTOR

• Original Certificate issued to Hunter Building Products Ltd on 15th September 1986. This amended version includes change of Certificate holder’s name, addition of spigot connector to range, reference to revised Building Regulations and associated text, revised British Standards and Conditions of Certification, and addition of Bibliography.

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Design Criteria

3.09 VENTILATION OF SOIL & WASTE SYSTEM

TRADITIONAL VENTILATION Ventilation of a soil and waste system is necessary to prevent water seals in traps being broken due to negative pressure or pressure fluctuations within the system. Broken seals permit foul air and smells to escape from the system, contaminating the air in and around the building. There are two ways of ventilating a soil stack, either externally to the atmosphere, or with an Air Admittance Valve sited in a non-inhabited space within a building.

Venting cage or cover allowing free air flow 900 mm min

Less than 3 m Discharge stack Ventilating stack Branch ventilating pipe

Door, window, or other opening into a building

The termination of an externally vented system must comply with the dimensional requirements illustrated in the diagram on the right. 3.10 TYPICAL STUB STACK IN COMPLIANCE WITH BUILDING REGULATIONS

Pan Connector to suit WC outlet 1. If WC, to BS5503 and depending on layout, Hunter S224, S221, S254, S251, or S267 WC connectors can be used. 2. If old type WC, to BS1213 the Hunter S231 and S248 WC connector and gasket should be used.

Stub Stacks A group of appliances may be connected above ground into a ventilated discharge stack or into a drain via an unventilated stub stack. A stub stack consists of a short length of 110mmdiameter pipe capped off with an access fitting (S667). Where one or more stub stacks are connected directly to an underground drainage system, ventilation must be provided via a vent stack or soil and vent pipe at the head of the drain. The distance from the finished floor level to the drain invert must not exceed 1.3 metres. While the highest connection should be within 2 metres to comply with Approved Document H of the Building Regulations 2002 Edition.

DS663 (871/2˚Rest Bend) Note: The loading on a stub stack should not exceed 5L/s.

Please note that there is a variation between the requirements of the Building Regulations and Part 2 of BS EN 1205.

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Design Criteria

3.11 BOSS CONNECTIONS

VERSATILE AND SIMPLE TO INSTALL To make life easy for the installer Hunter’s 82mm, 110mm and 160mm boss fittings are supplied with either open or unopened bosses that are the same size. In addition, boss adaptors offer the simplest waste to soil connections, whether using push-fit or solvent weld pipework. Unopened bosses may be accessed using standard 48mm hole cutter.

HUNTERS ‘EASY TO USE’ BOSS CONNECTIONS 32mm

40mm

50mm

CREATES PUSH-FIT CONNECTION – PUSH-FIT PIPEWORK TO BSEN1451

W58

W59

S751

CREATES PUSH-FIT CONNECTION – SOLVENT WELD PIPEWORK TO BS5255

W59

W58

CREATES SOLVENT WELD CONNECTION – SOLVENT WELD PIPEWORK TO BS5255

W104

W106

S750

ANGLED OPTIONS FOR SOLVENT WELD PIPEWORK S753

2.5° 90°

W104 + W111

W106 + W112

W725

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Design Criteria

3.12 WASTE MANIFOLD

PREVENTION OF CROSS FLOW In any soil and vent pipe the discharge from one branch pipe must not be able to flow across and enter an opposing branch pipe connection. A PVCu branch between 82mm and 160mm diameter has a restricted area of 200mm as shown in diagram (a) whilst a small diameter branch pipe up to 63mm has a restricted area dependent on the discharge stack diameter. See table adjacent.

Branch diameter 82mm to 160mm

Section

Centre line of opposed branch not to be above this point

PVC stack dia. 82 110 160

Height of restricted area 90 110 250

Small branch diameter 63mm max.

Centre line of opposed branch not to be below this point

200mm

RESTRICTED AREA FOR OPPOSING SMALL DIA. BRANCH PIPES

Unopposed connection permissible in this area

(See table above)

200mm

Section

Section

Plan

Plan

Plan

(a) Restricted connection area on stack

(b) Examples of permitted connections

(c) Opposing waste pipes

HUNTER’S WASTE MANIFOLD IS DESIGNED TO PREVENT CROSS FLOW Plumbing in the bathroom or WC is made easier by using the Hunter S200 Waste pipes may be connected to the S200 above floor level using any one of the four inlets to suit site conditions. The four waste inlets, will permit connections of extra pipework at a later date. The S200 will accept waste pipes to BS EN1451 and BS EN1566:2000,

The S200 fits neatly against a wall or into a corner of the room. The dimensions allow standard pipe or socket bracket to be used to support pipework. Should the need arise to gain access for rodding purposes, it may be done via one of the inlets.

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Design Criteria

HOW TO INSTALL A WC, BASIN AND BATH USING THE S200 WASTE MANIFOLD

Anti-Siphon Unit Basin

For maximum distance see table below

Centre line of WC Pan outlet to conform to BS5503 horizontal outlet (190mm)

Bath

NB. If the distance of the bath exceeds 3000mm 50mm Waste pipe must be used to conform with building regulations H1 1991.

Connecting 110mm to the S200 is made in the normal manner by use of the Hunter ring seal jointing technique, i.e. lubricating pipe or branch spigot prior to insertion. To open the closed bosses on the S200; • Cut open the required connection ports using a fine tooth saw. • For 50mm connections, solvent weld the W725 adaptor bends directly into the socket. • For 32mm connections use the W58 rubber boss adaptor and either the P019 polypropylene spigot tail bends to (BS EN 1451: 2000) or W111 MUPVC spigot tail bends to (BS EN 1566). The W104 glued adaptor can only be used with MUPVC spigot tail bends • For 40mm connections use the W59 Rubber boss adaptor and either the P029 polypropylene spigot tail bends to (BS EN 1451: 2000) or the W119 MUPVC spigot tail bends (BS EN 1566). The W106 adaptor can only be used with MUPVC spigot tail bends

H

WC

BATH

70mm 60mm 50mm 40mm

240mm 320mm 545mm 770mm

1700mm 1790mm 2340mm 2870mm

30mm 20mm 10mm F/L

1000mm 1200mm 1365mm 1620mm

3270mm 3760mm 4800mm 5300mm

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Design Criteria

WASTE MANIFOLD EXAMPLES FOR USE S200

W151 W151

W718 Basins W714

W718 Basins W714 50mm S214 or S246 S200

DS663

DS211

To Drain

PLAN

S200

PLAN

PO10/W78

Basin

32mm

32mm PO20/W79

PO21/W81

40mm Bath

Basin 40mm

Bath

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Design Criteria

WASTE MANIFOLD EXAMPLES FOR USE

Basin PLAN

ELEVATION A - A 32mm 110mm SVP

S254

110mm

40mm

40mm

40mm

S200

40mm

FFL

Bath Kitchen A

A

Basin

PLAN

ELEVATION B - B

32mm

External 110mm SVP 110mm FFL

40mm B

B Bath

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Design Criteria

3.13 WC CONNECTIONS

Z

PRODUCT CODE S224 STRAIGHT PAN CONNECTOR ALL PURPOSE TAIL • For use with BS5503 H/O pans. • May be used with PVCu, cast iron or clayware pipes. • Ideal for refurbishment work. • Ideal for connecting to concealed pipework. • Smooth wipe clean finish.

Z=

X

Min

Max

150mm

250mm

Where dimension ‘X’ exceeds 160mm use S224 in conjunction with S226 extension piece.

Measure between the pipe end and the pan spigot, dimension ‘X’. Add on 90mm to allow for insertion depths.

Remove the finned seal and mark a cut line on the connector.

Cut the connector spigot squarely using a fine toothed saw. Remove any burr.

Replace finned seal onto connector. Lubricate finned seal using silicone lubricant.

Push connector into pipe ensuring it is fully home. Lubricate pan spigot and install into connector.

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Design Criteria

3.13 WC CONNECTIONS CONT-

WC FLOAT SYSTEM USING THE S253 VARIABLE WC CONNECTOR SOIL STACK

S334 Branch

S312 + S253

*S750 may be solvent welded into a side boss to allow for a 50mm traditional ventilation pipe (if required)

S312 + S253 WC S312 + S253 WC

Minimum gradient on horizontal float should be 1/2˚ or 9 mm/m

S312 + S253

WC

S312 + S253 WC Note: If solvent jointing is preferred use S292 instead of S312 and S297 instead of S334 WC

S253 variable WC connector

S312 branch

Back to wall closet S253 variable WC connector S312 branch

Section

S246 Rodding eye

Close coupled closet

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Design Criteria

3.13 WC CONNECTIONS CONT-

PRODUCT CODE S253 WC FLOAT SYSTEM USING THE S253 VARIABLE WC CONNECTOR CONT-

SOIL STACK

345 +/10mm

① 800mm

②

800mm

③ 800mm

④ 800mm

⑤

Float laid to fall of 1/2˚ (9mm drop/1 metre run)

WC connector to suit BS5503 horizontal outlet pan

WC

S217/220

90mm

WC Position

① ② ③ ④ ⑤ H (mm)

190mm Up to +/-2˚ movement on joint between branch and WC connector

125 134 143 152 161

Approx angle of 18˚ WC connector

16˚

F.F.L. *For pan centres less or greater than 800mm contact the technical department at Hunter Plastics Limited

13˚

11˚

7˚

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Design Criteria

3.14 DRAIN CONNECTOR FLEXIBLE WASTE ADAPTOR

PRODUCT CODE DS25 The DS25 will accept two waste pipes of either 32mm or 40mm diameter. It is made from flexible EPDM and manufactured with one inlet open and one closed. The closed inlet can be opened with a sharp knife. The DS25 can be fitted into a socket by replacing the ring seal with it, or inside the bore of 110mm pipe, see the illustration below.

Waste pipe

DS25

110mm socket

Ground floor installations only

110mm pipe

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Design Criteria

3.15 ACCESS

ACCESS Access to stacks are to be fitted above the over-spill level of the appliances to ensure ease of access as and when it is required. All discharge pipework must be easily accessible and traceable access covers and cleaning eyes should also be positioned to allow cleaning and maintenance equipment to be easily inserted into the pipework and to permit cleaning and clearing of all parts of the system. Sanitary pipework systems should be capable of being tested to ensure that the required performance is attained. Whilst adequate access should be provided to enable these tests to be carried out. 3.16 GULLIES

GULLIES Ground floor appliances that produce waste water only may discharge into a gully. Waste pipes from such appliances should terminate above the gully’s water seal and below the gully grid.The design of Hunters back inlet gullies allow several appliances to discharge to the same gully. 3.17 OVERFLOW DISCHARGE

Hunter’s Overflow System The 22mm polypropylene and unplasticized polyvinyl chloride (PVCu) pipe is available in white in three metre Iengths. The range of high temperature MuPVC overflow fittings are designed so that they can be either push fit onto the polypropylene pipe or solvent welded onto the unplasticized polyvinyl chloride (PVCu) pipe. Hunter’s 22mm pipe can be connected to other manufacturer’s pipe by using the universal adaptor O220. Overflow Pipes To warn occupiers of problems with the stopvalve before the water level reaches the spillover level of the cold water storage cisterns, they must be fitted with a warning pipe. The pipe must be adequately supported to have a consistent fall to a conspicuous position, preferably outside the building. To evacuate the incoming water before the stopvalve becomes submerged the pipe should be positioned to create a Type B air gap and be a larger diameter than the incoming water supply, at least 22mm outside diameter. See diagram. Bore of Supply Pipe

Type B Air Gap

Not exceeding l4mm

20mm

Exceeding l4mm but not exceeding 21mm

25mm

Exceeding 21mm but not exceeding 41mm

70mm

Exceeding 41 mm

twice bore of supply pipe

A warning pipe must not be fitted with a flap on the outlet to prevent icy wind from blowing along the pipe and freezing the stopvalve in the closed position. Instead, it should be fitted with a bend or tee. When fitted in unheated roof spaces warning and overflow pipes must be insulated. They should also be included in the maintenance schedule to ensure that they comply with all of the above.

Supply pipe inlet Stop valve

Type ‘B’ Gap

Overflow

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Design Criteria

3.17 OVERFLOW DISCHARGE CONT-

Conspicuous Discharge The use of internal bathrooms means that it is not always possible to discharge overflowing water outside the building. Therefore, Hunter Plastics Ltd manufactures a combined bath/cistern waste and overflow (W040CF) so that the water conspicuously overflows into the bath. Combined Warning Pipe Two or more warning pipes may discharge to a combined warning pipe providing that the overflowing cistern is easily detected and that the overflow from one cistern cannot discharge into another. This is achieved by providing a 25mm air gap between the cistern’s warning pipe and the combined overflow pipe. The combined warning pipe should discharge externally but in exceptional circumstances the termination point may have no visible outlet. See diagram.

22mm overflow pipe

25mm air gap

W711 50mm socket used to form Tundish W717 32 x 50mm reducer

W84 Tee W116 32mm bend