plumbing design criteria

Hunter Soil and Waste Systems

DESIGN CRITERIA3.00

3.01 Design Criteria3.02 Hunter Plumbers Bits3.03 Depths of water seal in traps3.04 Pipework and sizing3.05 Branch Connections to Stacks3.06 Ventilation of Discharge Stack3.07 Air Admittance Valve3.08 Air Admittance Valve BBA

Specification3.09 Ventilation of Soil & Waste3.10 Stub Stack3.11 Boss Connections3.12 Waste Manifold3.13 WC Connections3.14 Drain Connector Flexible

Waste Adaptor3.15 Access3.16 Gullies3.17 Overflow Discharge

3.01 DESIGN CRITERIA

All sanitary pipework and drainage installations mustsatisfy Part H1 of the approved documents to theEngland, Wales and Northern Ireland BuildingRegulations 1991 and 1994 respectively. Also theBuilding Standards (Scotland) amendment regulations1990. These requirements can also be met byfollowing the relevant recommendations of BS EN12056:2000 which contains information onperformance rates and discharge levels from sanitaryappliance including, recommendations for design,testing, installation, and maintenance for all aboveground non-pressure pipework systems.

Regular consultation is essential between plumbingengineers and architects through every stage ofdesign. This helps to ensure the positions of sanitaryappliances and ducts permitting efficient pipeworkinstallation at minimum cost.

In addition, a well designed and installed sanitarywaste 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.

Design Criteria

3.02 HUNTER PLUMBERS BITS TRAPS

To comply with Approved Document H of the BuildingRegulations all points of discharge into the drainagesystem should be fitted with a water seal trap toprevent foul air from the system entering the building.Plus, the waste pipe diameter and gradient must beselected to maintain a minimum of 25mm water seal inthe trap after an appliance has been used. However,Hunter manufacture a range of resealing traps andanti-siphon units that may be used where the integrityof the water seal cannot be guaranteed. Hunter's trapscan be dismantled for inspection and maintenance,which should be done on a regular basis to ensure thetrap functions correctly.

3.03 DEPTHS OF WATER SEAL IN TRAPS

BS EN 12056 - 2: 2000 requires that traps thatdischarge to a soil stack have a 75mm water seal,however, 50mm water seal traps can be fitted tobaths; shower trays and basins without plugs fittedwith spray taps. 38mm water seal traps can only beused on ground floor flat bottomed appliances thatdischarge to a back inlet gully trap. Traps with outletdiameters greater than 50mm, should have a minimumwater seal depth of 50mm.

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Appliance Trap outlet size(mm)

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

*

*

**

*

Design Criteria

3.04 PIPEWORK AND SIZING

SIZES OF BRANCH PIPESSince June 2001 British Standard, Euro Norm BS EN 12056: 2000 Gravity Drainage Systems Inside Buildings has replaced BSEN12056-2:2000 as the standard governing the installation of above ground pipework. The United Kingdoms sanitarypipework system of single stack layouts requiring swept entry on equal branch junctions and our method of designing ranchwaste pipes running full are included in the new standard, listed as System III and in the National Annex of part two. Thenational annex will allow the UK to continue to design and install sanitary pipework with only some minor alterations from ourprevious standard. Amendments to Par H of the Building Regulations that come into force in April 2002 will bring it in line withthe new British Standards.

Pipes serving a single appliance should have the same diameter as the appliance trap (see table on previous page). However byincreasing the pipe diameter the length of the unventilated waste can be lengthened. Where the larger branch pipe is used thetrap diameter is not increased but 50mm of the smaller pipe is used before increasing the pipe size. To prevent the need foradditional ventilation of the pipework the pipe lengths are restricted as shown in the following DESIGN OF BRANCHDISCHARGE PIPES chart, the UNVENTILATED BRANCH CONNECTION TO STACK diagram, and the DESIGN CURVE FORBASIN WASTE PIPES diagram. Further details can be found in Approved Document H and BS EN 12056-2: 2000.

DISCHARGE UNIT METHODA numerical value is assigned to each sanitary appliance to express its load producing property. he unit values of all sanitaryappliances discharging into the discharge stack and internal drainage are calculated to find the pipe diameter by the methodgiven in the British Standard.

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Appliance No. of Trap size mm Branch dia. Max. length of Max. No. of Action to be Trap type Branchappliances and trap type branch in m bends guarded Gradient in

against mm/m

Wash Basin 1 32P 32 1.7 A EX SS T B 22or Bidet 1 32P 40 3.0 2A EX SS T B 18-45

1 32P 32 3.0 2A EX SS R AV 18minASU

Up 32P 50 4.0 NONE EX IS SS T B 18-45to 45 32P 50 7.0 A EX IS SS T B 18-45

R AVASU

10 32P 50 10.0 A NL EX IS SS T B 18-45AVASU

Shower, Bath, 1 40P or S 40 3.0 A NL EX SS T B 18-90Sink LDomestic Washing 1 40P 40 3.0 A NL EX T 18-45Machine or DishwasherWC 1 100P or S 110 6.0LL A NL 18min

2-8 100P or S 110 15.0 2A 9-908+ 100P or S 110 NL A NL AAV min91 40P or S 40 3 SAP A NL EX T 18-90

Bowl Urinal NL 40P or S 50 SAP A EX IS T 18-90Slab Urinal 1 60P or S 60 3 SAP A NL EX T 18-90for Max 7 PeopleTrough Urinal 1 50P or S 50 3 SAP A EX T 18-90

NOTES:A: Only use swept bends or branches AAV: Air admittance Valve ASU: Ant-siphon unit AV: Anti-vacuum trap B: Bottle trapEX: Excessive deposits IS: Induced siphonage L: Longer branches are allowed which may result in noisier discharge and blockagesLL: Longer branches are allowed in BS EN 12056-2:2000 NL: No limit R: Resealing trapSAP: As short as practicable to limit excessive deposits SS: Self-siphonage T: Tubular trap

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

Design Criteria

3.04 PIPEWORK AND SIZING CONT-

UNVENTED BRANCH CONNECTIONS TO STACK

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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 90mm/m

Vent pipe connection above spillover level

Spillover level

Slope (see graph below)Slope between 18 to 90 mm/m

6 m max for single WC

Slope 18 mm/m min

WC

Bath

Sink Washbasin

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

750 mm max

Dischargepipe

BRANCH VENTILATION PIPES DESIGN CURVE FOR 32 mmUNVENTED WASH BASIN WASTE PIPES

Design Criteria

3.05 BRANCH CONNECTIONS TO STACKS

SINGLE STACK SYSTEM (SYSTEM III)Building regulations and code of practice requirements1.The distance between the lowest branch connection tothe discharge stack and the invert of the bend at the footof the stack should not be less than the table below:

LOW RISEup to 3 storeys 450 mm

MULTI-STOREYup to 5 storeys 750 mmOver 5 storeys Ground floor connections

should discharge direct to drain or into their own stack.

Over 20 storeys 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 tofacilitate multi point connections to the stack,eradicating the danger of crossflow even within the dangerzones marked by A and B on the soil stack below.

BRANCH CONNECTIONS TO STACKS

3.06 VENTILATION OF DISCHARGE STACK

Ventilation of the discharge stack is required toprevent water seals in traps from being lost bypressure which can develop in the system, allowingfoul air to escape.

Separate ventilation of branch pipes will not beneeded if the length and slope of the branch doesnot exceed those in the diagram below.

In cases where these figures are exceeded, thebranch pipe should be ventilated by a branchventilating pipe or by a Hunter anti-siphon unit.

Key

A small similar sized connections not exceeding 65 mm and directly oppositeshould be offset by 110mm on a 100 mm diameter stack 250 mm on a 150mm diameter stack.

B Angled connection or 50 mm diameter parallel junction where a wastebranch directly opposite a WC would enter the stack within 200 mm belowthe WC connection centreline.For further information see section 3.11

A

450 mmmin

Dangerzone

Draininvert

MinimumRadius 200mm

WC

200 mmOffset

Lowestconnection

50 mmparalleljunction

50 mm

B


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


Slope between 18 to 90mm/m

Vent pipe connection above spillover level

Spillover level

Slope (see graph below)Slope between 18 to 90 mm/m

6 m max for single WC

Slope 18 mm/m min

WC

Bath

Sink Washbasin

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

750 mm max

Dischargepipe

BRANCH VENTILATION PIPES DESIGN CURVE FOR 32mmUNVENTED WASH BASIN

WASTE PIPES

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Design Criteria

3.07 AIR ADMITTANCE VALVE

AIR ADMITTANCE VALVESAir admittance valves are designed to decrease thenumber of suspended floor and roof penetrations requiredto accommodate soil and ventilating stacks withoutreducing the effectiveness or performance of the system.They also reduce the quantity of components required tocomplete a system.

Figure 1 Relief Valve

The valve contains a diaphragm which under light springpressure is normally held closed, containing foul air withinthe system. When there is a discharge from an appliance, anegative air pressure is produced in the system. Thispressure causes the diaphragm in the valve to lift from itsseat, allowing air to be drawn into the system: this intakeand the rapid equalisation of air pressure prevents foul airescaping and prevents the water seals in traps from beingbroken.

Polystyrene tops can be fitted over the valve cover afterinstallation, providing insulation for the valve in use.

The valve incorporates a socket for solvent welding to 110mmPVCu pipe to BS EN1329:2000. It can be fitted to sanitarypipe work systems of buildings up to 5 storeys high. Air admittance valves must be installed in a vertical positionabove the flood level of the highest appliance connected to

any soil stack. It should be situated in a non-habitable areaof the building, e.g. the roof space, where it will be easilyaccessible and there is reduced risk of freezing. Care mustbe taken to prevent contamination of moving parts. In theevent of accidental damage or vandalism once installed, thecover can be unscrewed and the damaged part (s)replaced.

The underground drain which serves a group of stacks towhich air admittance valves are fitted may requireadditional ventilation. This will minimise the effects ofexcessive back pressure if blockage should occur in a drain.In determining the requirement for additional ventilation tothe underground drainage system the following rules can beused for general guidance (see figure 9).

I. Up to and including four domestic dwellings up to 3 storeyshigh, additional drain ventilation is not necessary.

2.Where an underground drain serves more than four suchdwellings which have soil systems fitted with an air admittancevalve, the drain must be vented as follows:

a.In the case of five to ten such dwellings, additionalconventional ventilation must be provided at the head of theunderground drainage system.

b.In the case of eleven to twenty such dwellings, additionalconventional ventilation must be provided at the head andmidpoint of the underground drainage system.

Moving sealcarrier

Star-lokwasher

Springretainer

Stainlesssteel spring

Screw cap

110mm soil pipe

Outer body

Inner body

Seal

Cover

Positive pressure (closed position)

Negative pressure (open position)

Diaphragmseal

Soil stack without Hunter Relief Valve andHunter Anti-Siphon Valve

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ROOF TRUSS

ROOF SPACE

Vent Cowl

Weathering Slate

32mm pipe

40mm pipeBath

Wash hand basin

Design Criteria

3.07 AIR ADMITTANCE VALVE CONT-

3.08 AIR ADMITTANCE BBA SPECIFICATION

PRODUCT

THIS CERTIFICATE REPLACESCERTIFICATE No 83/1066 ANDRELATES TO THE HUNTER AIRADMITTANCE VALVE AND HUNTERANTI-SIPHON UNIT, FOR ABOVE-GROUND DRAINAGE SYSTEMS.

The products are for usewithin buildings in aboveground drainage systems designed inaccordance with thisCertificate.

The valve and unit provide ameans of ventilation to thedrainage system to prevent the loss ofwater seals in traps andconsequent release of foul air into thebuilding.

The drainage systems and the installation and use of the productsmust be in accordance with the conditions set out in the Design Dataand 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 ofAgrment the requirements of the Building Regulations to which airadmittance valves can contribute in achieving compliance. In theopinion of the BBA, Hunter Air Admittance Valve and Hunter Anti-Siphon Unit, used in accordance with the provisions of this Certificate,will contribute to meeting the relevant requirements.

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 forcleaning 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.

Requirement: Regulation 7 Materials and workmanship

Comment: The products are acceptable.

2 The Building Standards (Scotland) Regulations 1990 (as amended)

In the opinion of the BBA, Hunter Air Admittance Valve and HunterAnti-Siphon Unit, if used in accordance with the provisions of this Certificate, will satisfy the various Regulations as listed below.

Regulation: 10 Fitness of materials

Standards: B2.1.B2.2 Selection and use of materials, components and other manufactured products


Regulation: 24 Drainage and sanitary facilities

Standard: M2.2 Drainage system

Comment: 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 HunterAnti-Siphon Unit, if used in accordance with the provisions of this

Certificate, will satisfy the various Building Regulations as listed below.

Regulation: B2 Fitness of materials and workmanship


Regulation: N2 Drainage Systems

Comment: 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 acrylonitrile-butadiene-styrene (ABS) inner body, seal carrier, spring retainer andcover, an unplasticized polyvinyl chloride (PVCu) outer body andscrew cap, a neoprene diaphragm seal to BS 2752 :1990, a nitrileseal washer to BS EN681:1996, a stainless steel spring and astainless 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 BSEN681:1996, and a stainless steel Star-Lok washer (see Figure 2).

4.3 The Air Admittance Valve incorporates a socket for solvent weldingto 110mm PVCu soil pipe to BS EN1329:2000

Soil stack with Hunter Relief Valve and Hunter Anti-Siphon Valve

Vent Cowl not required

Weathering Slate not required

Alternative positions for HunterRelief Valve

Hunter Relief Valve

110mm Soil pipe not required

Bends not required

3.00

ROOF TRUSS

ROOF SPACE

Hunter Anti-Siphon Unit

Bath

Wash hand basin

32mm reducer

40mm tee 40mm pipe

Design Criteria

4.4 With the use or an appropriate adaptor to BS EN1329:2000 theHunter Air Admittance Valve can be connected to othermaterials (eg cast iron).

4.5 The Anti-Siphon Units are available in five spigot outlet sizes toconnect to either 32 mm or 40 mm waste systems to BS EN1566/BSEN1566:2000 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 washersand springs are bought in.

4.8 Continuous quality control is carried out during manufacture andassembly of the valves and units, including visual checks, checks ondimensional accuracy, airtightness and stress relief. At hourly intervals theABS components of the Hunter Air Admittance Valve are assembled andchecked for freedom of rotation and flatness. The raw materials andbought-in components are also subject to quality control checks.

Figure 2 Hunter Anti-Siphon Unit

5 Delivery and site handling

5.1 The manufacturers emblem and the BBA identification markincorporating the number of this Certificate are printed on the coverof each Hunter Air Admittance Valve.

5.2 The valves are individually packed in plastic bags or cardboardboxes and should remain stored upright and so protected until theyare required for use.

5.3 The manufacturers emblem and the BBA identification markincorporating the number of this Certificate are printed on the coverof each Hunter Anti-Siphon Unit.

5.4 The units are packed in a plastic bag. Each bag carries a labelbearing the BBA identification mark incorporating the number of thisCertificate.

DESIGN DATA

6 General

6.1 When used in accordance with the provisions of thisCertificate in above-ground drainage systems designed inaccordance with BS EN 12056-2: 2000, the valves:

(a) admit air under conditions of reduced pressure in the dischargepipes 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 thedischarge stack incorporating the valve is connected.

6.2 The Hunter Air Admittance Valve is for use on discharge stacksserving up to five storeys.

6.3 The Hunter Anti-Siphon Unit is for use on branch discharge pipes.

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

7 Drainage system design

7.1 The following above-ground drainage systems, designed inaccordance with BS EN 12056-2: 2000 and incorporatingHunter valves and units, have been assessed as satisfactory:

(a) Domestic Buildings (eg bungalows, houses, multi-storey flats, hallsof residence) - satisfactory drainage systems incorporating the valvesand units are shown in Figures 3, 4 and 5.

(b) Non-domestic buildings (eg offices, factories, schools and othertypes of public buildings) - satisfactory drainage systems incorporatingthe valves and units are shown in Figures 6 and 7.

Note: In each case referred to, different combinations of sanitaryfittings are permissible, provided the siphonage effects occurringwithin the systems are not made more onerous. Where individualappliances are liable to self-siphonage (eg S-trap connections) ventingwith an additional Hunter Anti-Siphon Unit may be required.

Figure 3 Typical domestic installation

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 positionabove the flood level of the appliance. being served.

7.3 To contribute to the ventilation of the underground drain and tominimise the effects of excessive back pressures when a drain blockage.occurs, the branch or main drain serving a stack or stacks fitted withHunter valves and units may require venting at point upstream of thestack 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 morethan four such dwellings equipped with the valve or unit, the drainshould be vented according to the following rule, by either aconventional open-topped ventilation or a discharge stack:5 to 10 such dwellings - conventional ventilation to be provided at thehead of the system.11 to 20 such dwellings - conventional ventilation to be provided at themid-point and at the head of the system.

(b) For multi-storey domestic dwellings (other than those referred toabove) and non-domestic buildings, conventional drain venting shouldbe provided if more than one such building, each equipped with thevalves and units, is connected to a common drain which is not itselfvented by means of a ventilation stack or a discharge stack not fittedwith a valve or unit.

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Spigot tosocket fitting

All dimensions in millimetres

Star-lokwasher

Diaphragmseal

Seal washer

Vent ducts

61

Variable spigot size

22

36

Hunter Air Admittance Valve fitted aboveflood level


Bath

Wash basin

P-trap

P-trap

110mm soil and vent pipe 40mm pipe

32mm pipe

Sink

Design Criteria

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

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.

3.00

Hunter AirAdmittance Valve


Bath

32mm pipe

110mm pipe

110mm pipe

40mm pipe

Wash hand basin


Bath

32mm pipe

Wash hand basin

40mm pipe


Hunter Air Admittance Valveor conventional open stack

Bath

32mm pipe

Wash hand basin

40mm pipe

Design Criteria

Figure 5 Domestic discharge system

Figure 6 Commercial and public discharge system

Notes:

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.

Notes:

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.

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Bath

32mmpipe

40mm pipe

Hunter Anti-Siphon unit

Wash handbasin

Bath

32mmpipe

40mm pipe

Hunter Anti-Siphon unit Hunter Air Admittance Valve

Hunter Air Admittance Valve

Up to 5 WC connections

Up to 5 WC connections

Wash handbasin Sink

Sink

P-trap

P-trap

40mm pipe

40mm pipe

Long radius bend

>110mm diameter

maximum 5 floorsmaximum 2 groups ofappliances per floor

Up to 5 wash basins

Up to 5 wash basins

40mm ASU

ASU ASU ASU

P-traps

Typical P-trap installation

Typical S-trap installationS-traps or P-traps

can be used

S-traps or P-traps can be used Maximum 5 floors

50mm minimum

50mm minimum

160mm pipe110mm pipe

Design Criteria

Figure 7 Permitted number of appliances in non-domestic buildings (eg offices, factories, schools and other types ofpublic buildings)

Figure 8 Typical installation of the Anti-Siphon Valve

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.

Maximum 2 or 5 groups of appliances per floor (1 or 3 groups in congested circumstances)

Sanitary appliance

Bottle/tubular trap


Vacuum releases diaphragm - pressure neutralised

Negative pressure areaPlug of water flowing

full bore

110mm dia pipe

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110mm dia pipe

Hunter Air Admittance Valve

110mm dia pipe

(i) 1 to 4 storeys (ii) 1 to 5 storeys (iii) 1 to 5 storeys

Hunter Anti-Siphon Uniton each storey

Hunter AirAdmittance Valve

5(3)

5(3)

5(3)

5(3)

2(1) 5(1)

5(1)

5(1)

5(1)

5(1)

2(1)

2(1)

2(1)

2(1)

9212 tee

300mm maxdistance centreline of unit tocrown of trap

Solvent weldTee

Constant76mm seal

Water level retained due toHunter Anti-Siphon Unit

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

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7.4 In installations other than as shown in Figure 9 stacks should not befitted with the valves when the connecting drain(s) are subject to periodicsurcharging or are fitted with intercepting traps. An open-toppeddischarge stack or ventilating stack should be used in such cases.

7.5 The valve should be installed within the building, preferably in a non-habitable 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 byvandals.

7.6 If the valve is to be installed in, or in close proximity to, a habitablespace where noise of operation may cause a nuisance then considerationmust 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 Unitis required within 300 mm of the trap (see Figure 8).

7.8 To prevent induced siphonage in a row of wash basins, aHunter Anti-Siphon Unit should be fitted near the end of the branchremote from the discharge stack (see Figure 6).

7.9 The Anti-Siphon Unit must be fitted in a vertical position above thepipe being ventilated.

7.10 Air admittance valves should not be used when the soil stackprovides 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 stackwhen they are subjected to a reduced pressure and therebyprevent loss of the water seals in appliance traps.

8.2 Under conditions of increased pressure in the drainage system, eachvalve will remain closed, thereby preventing the release of foul air into thebuilding.

8.3 A pressure increase sufficient to raise the level of the water seal or tocause foul air to bubble up through the seal is an indication that a drainblockage has occurred or that the system is being overloaded or otherwisemisused.

9 Durability

Hunter valves and anti-siphon units are - manufactured frommaterials conventionally used in drainage systems. Repeatedopening and closing will not adversely affect the sealing or

operation of the valve. When used in the context of this Certificate theproduct will not be subject to significant deterioration and will have a lifeequivalent to that of the drainage system in which it is installed.

Design Criteria

INSTALLATION

10 Procedure

10.01 Installation must be carried out in accordance with themanufacturers instructions for the products.

10.2 The Hunter Air Admittance Valve must be fitted to the top of thedischarge stack above the over-spill level of the highest appliance. The110mm diameter spigot tail valve may be push fitted into ring seal socketsafter applying Hunters lubricant to the spigot tail, or solvent welded intoPVCu sockets. The 110mm socket outlet is for solvent welding to PVCupipe.

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

The cementing procedure should follow the instructions on the Huntersolvent cement label. The 32mm, 40mm and 50mm metric waste pipesizes may be jointed to polypropylene on thermoplastic systems, using themethods described here.

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

11 Maintenance

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

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

Technical Investigations

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

12 Tests

Tests were carried out to determine:

effect of pressure cycling, performance in use an a stack when tested inaccordance with BS EN1055:1996, airtightness under normal operatingconditions, airtightness when tested to pressures of 40mm and 200mmwater gauge, airtightness at low positive pressure, reduced pressurerequired to open the valve, watertightness under positive pressure, effecton the seal depth of a bottle trap when fitted near an anti-siphon unit withthe discharge pipe running full, prevention of loss of trap seals due toinduced 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 ofmaterials, effects of impact drop test and correct functioning and effect ofrepeated operation.

13 Other investigations

13.1 The manufacturing process was examined, including the methodsadopted for quality control, and details were obtained of the quality andcomposition 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 inpipework and pipelines

BS 2752 : 1990(1997) Specification for chloroprene rubber compounds

BS 2782 Methods of testing plastics Part 1 Thermal propertiesDetermination of Vicat softening temperature of thermoplastics

BS EN1329:2000/BS EN727:1996, EN 1055: 1996 Specification forunplasticized PVC soil and ventilating pipes, fittings and accessories

Specification for P.P Waste Systems and Soil and Waste Discharge withinthe building structure Chlorinated Poly (vinyl chloride (PVC-c)BS EN1451:2000 and BS EN1566:2000, BS EN1566

BS EN 12056: 2000 Gravity drainage systems inside buildings

BS 6209 : 1982 Specification for solvent cement for non-pressurethermoplastics pipe systems

BS EN 752: 1998 Drain and sewer systems outside buildings

14 Conditions

14.1 This Certificate:

(a) relates only to the product that is described, installed, used andmaintained or set out in this Certificate;

(b) is granted only to the company, firm or person identified on the frontcover no other company, firm or person may hold or claim any entitlementto this Certificate;

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

(d) is copyright of the BBA.

14.2 References in this Certificate to any Act of Parliament, Regulationmade thereunder, Directive or Regulation of the European Union, StatutoryInstrument, Code of Practice, British Standard, manufacturers instructions orsimilar publication shall be construed or references to such publication in theform in which it was current at the date of this Certificate.

14.3 This Certificate will remain valid for an unlimited period provided thatthe product and the manufacture and/or fabricating process(es) thereof:

(a) are maintained at or above the levels which have been assessed andfound to be satisfactory by the BBA;

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

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

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

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

(b) the right of the Certificate holder to market, supply, install or maintain theproduct; and

(c) the nature of individual installations of the product, including methodsand workmanship.

14.5 Any recommendations relating to the use or installation of this productwhich are contained or referred to in this Certificate are the minimumstandards required to be met when the product is used. They do not purportin any way to restate the requirements of the Health & Safety at Work Act1974, or of any other statutory, common law or other duty which may existat the date of this Certificate or in the future; nor is conformity with suchrecommendations to be taken as satisfying the requirements of the 1974 Actor of any present or future statutory, common law or other duty of care. Ingranting this Certificate, the BBA does not accept responsibility to anyperson or body for any loss or damage, including personal injury, arising asa direct or indirect result of the installation and use of this product.In the opinion of the British Board of Agrment, Hunter Air Admittance Valveand Hunter Anti-Siphon Unit are fit for their intended use provided they areinstalled, used and maintained as set out in this Certificate. Certificate No86/1737 is accordingly awarded to Hunter Plastics Ltd.

On behalf of the British Board of Agrment

Date of Second issue: 24th November 1998

Original Certificate issued to Hunter Building Products Ltd on 15thSeptember 1986. This amended version includes change of Certificateholders name, addition of spigot connector to range, reference to revisedBuilding Regulations and associated text, revised British Standards andConditions of Certification, and addition of Bibliography.

DIRECTOR

3.00

3.09 VENTILATION OF SOIL & WASTE SYSTEM

TRADITIONAL VENTILATIONVentilation of a soil and waste system is necessary toprevent water seals in traps being broken due tonegative pressure or pressure fluctuations within thesystem. Broken seals permit foul air and smells toescape from the system, contaminating the air in andaround the building. There are two ways ofventilating a soil stack, either externally to theatmosphere, or with an Air Admittance Valve sited ina non-inhabited space within a building.

The termination of an externally vented system mustcomply with the dimensional requirements illustratedin the diagram on the right.

Design Criteria

Venting cage or coverallowing free air flow

900 mmmin

Less than 3 m

Discharge stackVentilating stackBranch ventilating pipe

Door, window,or otheropening into abuilding

Stub StacksA group of appliances maybe connected above groundinto a ventilated dischargestack or into a drain via an unventilated stub stack. A stub stack consists of a short length of 110mm-diameter pipe capped off with an access fitting(S667). Where one or morestub stacks are connecteddirectly to an undergrounddrainage system, ventilationmust be provided via a ventstack or soil and vent pipe atthe head of the drain. Thedistance from the finishedfloor level to the drain invertmust not exceed 1.3 metres.While the highest connectionshould be within 2 metres tocomply with ApprovedDocument H of the BuildingRegulations 2002 Edition.

Please note that there is avariation between therequirements of the BuildingRegulations and Part 2 of BSEN 1205.

1. If WC, to BS5503 and depending on layout,Hunter S224, S221, S254, S251, or S267WC connectors can be used.

2. If old type WC, to BS1213 the Hunter S231 and S248 WC connector and gasket should be used.

DS663 (871/2Rest Bend)

Note: The loading on a stub stack should notexceed 5L/s.

Pan Connector to suit WC outlet

3.10 TYPICAL STUB STACK IN COMPLIANCE WITH BUILDING REGULATIONS

3.00

3.11 BOSS CONNECTIONS

VERSATILE AND SIMPLE TO INSTALLTo make life easy for the installer Hunters 82mm, 110mm and 160mm boss fittings are supplied witheither open or unopened bosses that are the same size. In addition, boss adaptors offer the simplestwaste to soil connections, whether using push-fit or solvent weld pipework. Unopened bosses may beaccessed using standard 48mm hole cutter.

Design Criteria3.00

HUNTERS EASY TO USE BOSS CONNECTIONS

50mm40mm32mm

W58

W58

W59

W59

S751

CREATES PUSH-FIT CONNECTION PUSH-FIT PIPEWORK TO BSEN1451

CREATES PUSH-FIT CONNECTION SOLVENT WELD PIPEWORK TO BS5255

W104 W106 S750

CREATES SOLVENT WELD CONNECTION SOLVENT WELD PIPEWORK TO BS5255

ANGLED OPTIONS FOR SOLVENT WELD PIPEWORK

2.5

90 W104 + W111 W106 + W112 W725

S753

Design Criteria3.00

Plumbing in the bathroom or WC is made easier byusing the Hunter S200

Waste pipes may beconnected to the S200above 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 EN1451and BS EN1566:2000,

3.12 WASTE MANIFOLD

PREVENTION OF CROSS FLOWIn 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 restrictedarea of 200mm as shown in diagram (a) whilst a small diameter branchpipe up to 63mm has a restricted area dependent on the discharge stack diameter. See table adjacent.

RESTRICTED AREA FOR OPPOSING SMALL DIA. BRANCH PIPES

PVC stack dia. Height of restricted area82 90110 110160 250

Branch diameter82mm to 160mm

(a) Restricted connection area on stack (b) Examples of permitted connections (c) Opposing waste pipes

Centre line ofopposed branchnot to be belowthis point

Unopposedconnectionpermissible inthis area

(See table above)

Centre line ofopposed branchnot to be abovethis point

200mm 200mm

Section

Plan

Section Section

Plan Plan

Small branchdiameter63mm max.

The S200 fits neatly against a wall or into a corner of theroom. The dimensions allow standard pipe or socket bracket tobe used to support pipework.

Should the need arise to gain access for rodding purposes, itmay be done via one of the inlets.

HUNTERS WASTE MANIFOLD IS DESIGNED TO PREVENT CROSS FLOW

Design Criteria

Connecting 110mm to the S200 is made in the normalmanner by use of the Hunter ring seal jointingtechnique, i.e. lubricating pipe or branch spigot prior toinsertion.

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 spigottail bends to (BS EN 1451: 2000) or W111MUPVC spigot tail bends to (BS EN 1566). TheW104 glued adaptor can only be used withMUPVC spigot tail bends

For 40mm connections use the W59 Rubber bossadaptor and either the P029 polypropylene spigottail bends to (BS EN 1451: 2000) or the W119MUPVC spigot tail bends (BS EN 1566). TheW106 adaptor can only be used with MUPVCspigot tail bends

NB. If the distance of the bath exceeds3000mm 50mm Waste pipe must be used toconform with building regulations H1 1991.

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

H WC BATH

70mm 240mm 1700mm60mm 320mm 1790mm50mm 545mm 2340mm40mm 770mm 2870mm30mm 1000mm 3270mm20mm 1200mm 3760mm10mm 1365mm 4800mm

F/L 1620mm 5300mm

3.00

Centre line of WC Pan outletto conform to BS5503horizontal outlet (190mm)

Basin

Anti-Siphon Unit

For maximum distance see table below

Bath

Design Criteria

WASTE MANIFOLD EXAMPLES FOR USE

3.00

W714W714

Basins BasinsW718

S214 or S246S200

DS211DS663

W718W151 W151

40mmPO21/W81

PO20/W79

Bath

50mm

S200

S200

To Drain

PLAN

PLAN

Basin32mm

32mm

PO10/W78

Basin40mm

Bath

Design Criteria

WASTE MANIFOLD EXAMPLES FOR USE

3.00

PLAN

PLAN

B B

Bath

A AKitchen

Basin

ELEVATION A - A

32mm

S254

110mm

110mm SVP

40mm 40mm 40mm 40mmS200 FFL

ELEVATION B - B

FFL

Basin

32mm

40mm

Bath

110mm

External110mm SVP

Design Criteria

3.13 WC CONNECTIONS

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

Measure between the pipe end and the pan spigot,dimension X. Add on 90mm to allow for insertiondepths.

Where dimension X exceeds 160mm use S224in conjunction with S226 extension piece.

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.

X

3.00

Min Max

Z = 150mm 250mm

Design Criteria

3.13 WC CONNECTIONS CONT-

WC FLOAT SYSTEM USING THE S253 VARIABLE WC CONNECTOR

SOIL STACK

S334Branch

S312 + S253

S312 + S253

S312 + S253

S312 + S253

S312 + S253

S246Rodding eyeWC

WC

WC

WC

Minimum gradient on horizontalfloat should be 1/2 or 9 mm/m

WC

*S750 may be solvent welded intoa side boss to allow for a 50mmtraditional ventilation pipe (if required)

S253 variable WC connector

S253 variable WC connector

S312 branch S312 branch

Back to wall closet

Section

Close coupled closet

3.00

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

Design Criteria

3.13 WC CONNECTIONS CONT-

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

SOIL STACK

WC connector to suit BS5503horizontal outlet pan

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

125 134 143 152 161

18 16 13 11 7

H (mm)

Approx angle of WC connector

WC Position

345+/-10mm

S217/220

90mm

Up to +/-2 movementon joint between branchand WC connector

190mm

WC

F.F.L.

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

800mm

800mm

800mm

800mm

3.00

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 EPDMand 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

110mmsocket

Ground floor installations only

110mmpipe

DS25

3.00

Design Criteria

3.16 GULLIES

GULLIES

Ground floor appliances that produce waste water only may discharge into a gully. Waste pipes from suchappliances should terminate above the gullys water seal and below the gully grid.The design of Hunters backinlet gullies allow several appliances to discharge to the same gully.

3.17 OVERFLOW DISCHARGE

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 whenit is required. All discharge pipework must be easily accessible and traceable access covers and cleaning eyesshould also be positioned to allow cleaning and maintenance equipment to be easily inserted into the pipeworkand to permit cleaning and clearing of all parts of the system. Sanitary pipework systems should be capable ofbeing tested to ensure that the required performance is attained. Whilst adequate access should be provided toenable these tests to be carried out.

3.00

Hunters Overflow SystemThe 22mm polypropylene and unplasticized polyvinyl chloride (PVCu) pipe is available in white in three metreIengths. The range of high temperature MuPVC overflow fittings are designed so that they can be either push fitonto the polypropylene pipe or solvent welded onto the unplasticized polyvinyl chloride (PVCu) pipe. Hunters22mm pipe can be connected to other manufacturers pipe by using the universal adaptor O220.

Overflow PipesTo warn occupiers of problems with the stopvalve before the water level reaches the spillover level of the cold waterstorage cisterns, they must be fitted with a warning pipe. The pipe must be adequately supported to have aconsistent fall to a conspicuous position, preferably outside the building. To evacuate the incoming water beforethe stopvalve becomes submerged the pipe should be positioned to create a Type B air gap and be a largerdiameter than the incoming water supply, at least 22mm outside diameter. See diagram.

Bore of Supply Pipe Type B Air GapNot exceeding l4mm 20mmExceeding l4mm but not 25mmexceeding 21mmExceeding 21mm but not 70mmexceeding 41mmExceeding 41 mm twice bore of supply pipe

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

Stop valve

Type BGap

Supplypipe inlet

Overflow

Design Criteria

3.17 OVERFLOW DISCHARGE CONT-

3.00

Conspicuous DischargeThe use of internal bathrooms means that it is not always possible to discharge overflowing water outside thebuilding. Therefore, Hunter Plastics Ltd manufactures a combined bath/cistern waste and overflow (W040CF) sothat the water conspicuously overflows into the bath.

Combined Warning PipeTwo or more warning pipes may discharge to a combined warning pipe providing that the overflowing cistern iseasily detected and that the overflow from one cistern cannot discharge into another. This is achieved by providinga 25mm air gap between the cisterns warning pipe and the combined overflow pipe. The combined warningpipe should discharge externally but in exceptional circumstances the termination point may have no visible outlet. See diagram.

22mm overflow pipe

25mm air gap

W71150mm socketused to form Tundish

W717 32 x 50mm reducer

W84Tee

W11632mm bend

3.00 DESIGN CRITERIA3.01 Design criteria3.02 Plumbers Bits traps3.03 Depth of water seal in traps3.04 Pipework & sizing3.04 Pipework & sizing cont3.05 Branch connections to stacks3.06 Ventilation & discharge stack3.07 Air admittance valve3.07 Air admittance valve cont3.08 Air admittance BBA spec3.08 Air admittance BBA spec contTypical layout Fig 4. Domestic discharge Fig 5. Commercial/public discharge Fig 6. Permitted No. appliances non-domestic Fig 7Anti siphon unit installation Fig 8.Drain ventilation provisions Fig 9.Installation3.09 Ventilation of soil & waste 3.10 typical stub stack 3.11 Boss connections3.12 Waste manifold3.12 Waste manifold contWaste manifold ex. for useWaste manifold ex. for use cont3.13 WC connectors3.13 WC connectors cont3.13 WC connectors cont3.14 Drain connector flexible waste adaptor3.15 Access3.16 Gullies3.17 Overflow discharge3.17 Overflow discharge cont

plumbing design criteria

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