Plumbing Vents & Ventilation Systems PDF

designed system such as a “yoke vent” connection between the soil and vent stacks. VENTILATION  Portion of the drainage pipe installation intended to maintain a balanced atmospheric pressure inside the system...

designed system such as a “yoke vent” connection between the soil and vent stacks. VENTILATION  Portion of the drainage pipe installation intended to maintain a balanced atmospheric pressure inside the system Yoke or By-pass Vent  Vent Pipe- a pipe or opening used for ensuring the  a pipe connecting upward from a soil circulation of air in a plumbing system and for relieving or waste stack below the floor and the negative pressure exerted on trap seals. below horizontal connection to an adjacent vent stack at a point above Main Types: the floor and higher than the highest  the ‘backbone’ of the entire spill level of fixtures for sanitary system preventing  Connected to the Main Soil & pressure changes in the Waste Stack stacks.  The portion where waste does not travel through  Continues to the roof; the portion penetrating the roof is called the Vent Stack Through Roof (VSTR) Main Vent  the principal artery of the Circuit Vent venting system to which vent  a group vent pipe which branches are connected. starts in front of the  a.k.a. ‘Collecting Vent Line’ extreme (highest) fixture  serves as support to the Main connection on a Soil & Waste Vent horizontal branch and connects to the vent stack.  a.k.a. ‘Loop Vent’ Individual Vent or Back Vent  Serves a battery of fixtures  a pipe installed to vent a fixture trap, that connects Looped Vent with the vent system above  a vertical vent connection the fixture served or on a horizontal soil or terminates in the open air waste pipe branch at a point downstream of the last fixture connection and turning to a horizontal line above the highest overflow level of the highest fixture Other Types: connected there Unit, Common, or Dual Vent  Used in spaces without  an arrangement of partitions venting so installed that one vent pipe serve two (2) traps. Wet Vent  that portion of a vent pipe through which wastewater also flows through. Relief Vent  a vertical vent line that provides additional circulation of air between the drainage and vent systems or to act as an auxiliary vent on a specially Local Vent VENT TERMINATION  a pipe or shaft to convey foul air from a plumbing  VSTR shall terminate vertically not less than 150 mm fixture or a room to the outer air. above the roof nor less than 300 mm from any vertical surface nearby. Dry Vent  Each vent opening shall terminate:  a vent that does not carry liquid or water-borne wastes. Not less than 3.00 m from any openable window; Not less than 0.90 m above any openable window; Stack Vent Not less than 0.90 m away from any lot line, alley  the extension of a soil or waste stack above the highest and street horizontal drain connected to the stack. boundary lines. Vent Stack  Vertical vent pipes shall extend 3.00 m distant from any  the vertical vent pipe installed primarily for providing part of the roof that is used for human activities and circulation of air to and from any part of the soil, waste shall extend not less than 2.10 m above such roof. of the drainage system. The uppermost end above the roof has traditionally been referred to as Vent Stack VENT STACK & RELIEF VENTS Through Roof (VSTR)  Each soil or waste stack extending ten (10) or more storeys above the building drain shall be served by a REQUIREMENTS: parallel vent stack which shall extend undiminished in Vents REQUIRED size from its upper terminal at the roof and connect to  Each trap shall be protected against siphonage and the soil or waste stack at ground level and at every fifth backpressure through venting. floor levels with a “yoke vent”at a point below the Vents NOT REQUIRED horizontal soil or waste branch connection to the stack  on a primary settling tank interceptor which discharges and at the nearby vent stack above the same floor to through a horizontal indirect waste pipe into a provide a relief vent. secondary interceptor. The secondary interceptor shall  The size of yoke vent shall be not less in diameter than be properly trapped and vented. either the soil stack or the vent stack, whichever is  Traps serving sinks in an island bar counter. Such sink smaller. shall discharge by means of an approved indirect waste  The yoke vent connection at the vent stack shall be pipe into a floor sink or other approved type receptor. placed 1.0 m above the floor level and, by means of a wye branch at the soil stack, shall be placed below the SIZE OF VENTS: fixture branch serving that floor.  The sizes of vent piping shall be determined from its length and the total number of fixture units connected thereto. SANITARY SYSTEM PROBLEMS:  The diameter of an individual vent shall not be less than  Trap Seal Loss 32 mm (1-1/4”) nor less in size than one-half (1/2) the - Direct effect of the Minus & Plus Pressure inside diameter of the drain to which it is connected. the system due to inadequate ventilation of traps - Attributed to the following conditions:  Siphonage- direct and momentum GRADES & CONNECTIONS  All horizontal or branch vents shall be free from drops or sags & shall be graded and connected to drip back by gravity to the drainage pipe it serves.  Each vent shall rise vertically 152 mm above the highest level rim of the fixtures served before offsetting horizontally.  All vent pipes shall extend undiminished in size above the roof or shall be reconnected to the soil or waste stack vent at a point below the roof. The “vent stack through roof” (VSTR) shall be increased one (1) pipe size above the connection between the stack vent and the horizontal vent.  Two (2) fixtures having same level inlet openings, may Back Pressure Capillary Attraction be served by a common vertical vent pipe connected to an approved double branch fitting.  - Evaporation- caused by extreme temperatures, idleness - Wind Effects- strong winds blow the trap seal  Retardation of flow - Due to the effect of atmospheric pressure and/or gravity  Deterioration of the Materials - Due to the formation of acids Indirect Waste Pipe – is a pipe that does not connect directly with the drainage system but conveys liquid wastes by discharging into a plumbing fixture, interceptor or receptacle directly connected to the drainage system.  LOOP VENT A vent arrangement for a group VENTILATION of plumbing fixtures, consist of a The process of supplying or vent pipe which is connected to removing air by natural or the waste or soil branch artificial means to or from immediately before the first any space, such air may or fixture of the group. may have not been conditioned. VENT A pipe installed to provide a flow of air to and from a drainage system or to provide circulation of air LOOPED VENT within such system to A type of ventilation system used on protect the trap seal from fixtures in a room away from a wall or siphonage and backpressure. partition. VENT STACK, MAIN VENT A vertical vent pipe installed primarily for the purpose of providing circulation of air to or from any part of the building drainage system. STACK VENT, SOIL AND WASTE VENT The extension to the open air of a soil or waste stack above the highest horizontal branch drain or fixture branch connected to the stack. INDIVIDUAL VENT/BACK VENT Type of venting system where the vent connects with a single fixture trap, usually at the back and extends vertically and connects with a stack vent, a vent stack or branch vent. CIRCUIT VENT A branch vent which serves two or more traps and extends from in front of the last fixture connection of a horizontal branch to the vent stack. Circuit venting can be used when two or more fixtures, such as lavatories, are installed in a row. The circuit vent is connected to the waste drain line between the last two fixtures in the row. Then the circuit vent is connected to the main vent.  SEWAGE DISPOSAL SYSTEM capacity; shall be at least 0.9 m width and 1.5 m long; Liquid depth not less than 0.6 m nor more than 1.8m. Secondary compartment: maximum capacity of 1/3  DISPOSAL PHASE- the final stage of the plumbing total capacity of tank; minimum of 1 cum liquid process; where used water and water-carried wastes capacity are brought to various disposal outlets  In septic tanks having over 6 cum capacity, the secondary compartment should be not less than 1.5 m SEPTIC TANKS in length.maintain a slope of 1:10 at the bottom of the  A watertight covered receptacle designed and digestion chamber to collect the sludge and make it constructed to receive the discharge of sewage from a easily accessible from the manhole building sewer, separate solids from the liquid, digest organic matter and store digested solids through a  MANHOLES: period of detention, and allow the clarified liquids to  with at least two (2) manholes, 508 mm in min discharge for final disposal dimension; one over inlet, other over outlet. Wherever  SLUDGE- solid organic matter that are denser than first compartment exceeds 3.7 m in length, an water and settle at the bottom of the septic tank additional manhole required over the baffle wall.  SCUM- lighter organic material that rise to the surface of the water  SIZES OF PIPE INLET & OUTLET & THEIR VERTICAL LEGS:  EFFLUENT- liquid content of sewage  Inlet and Outlet pipes – diameter size not less than the sewer pipe Bacteria in septic tank to encourage decomposition:  Vertical legs of inlet and outlet pipes – diameter size not  Aerobic bacteria- relies on oxygen to survive less than the sewer pipe nor less than 104.6 mm.  Anaerobic bacteria- can survive in places without oxygen  LENGTH AND LOCATION OF INLET & OUTLET:  Shall extend 101.6 mm above and at least 304.8 mm  Minimum dimensions below the water surface L= 1500mm  Invert of the inlet pipe shall be at a level not less than W=900mm 50.8 mm above the invert of the outlet pipe. D=1200mm  VENT DIAMETER:  equal to the cross sectional area of the house sewer.  AIR SPACE:  Cover of septic tank shall be at least 50.8 mm above the back vent openings.  PARTITION (between compartments):  An inverted fitting equivalent in size to the tank inlet, DESIGN CRITERIA: but in no case less than 104.6 mm in diameter, shall be  PLANS: installed in the inlet compartment side of the baffle with  should show all dimensions, reinforcing, structural the bottom of the fitting placed midway in the depth of calculations, and such other pertinent data as needed. the liquid. Wooden baffles are prohibited.  QUALITY OF DESIGN:  STRUCTURE:  shall be such as to produce a clarified effluent of  Shall be capable of supporting an earth load of not less acceptable standards and shall provide adequate space than 14.4 kPa for sludge and scum accumulations.  CAPACITY:  MATERIALS:  The capacity of septic tanks is determined by the  constructed of durable materials, not subject to number of bedrooms or apartment units in dwelling excessive corrosion or decay, shall be watertight. occupancies; by the estimated waste/sewage design Material: cement (most common) or pre-fabricated cast flow rate for various building occupancies; or by the iron number of fixture units of all plumbing fixtures; whichever is greater.  COMPARTMENTS:  The capacity of any one septic tank and its drainage  have a minimum of 2 compartments: system shall also be limited by the soil structure First compartment: not less than 2/3 capacity of the classification in its drainage field. total capacity of tank; not less than 2 cum liquid  LOCATION:  Public sewer may be considered as not being available if  Should not be located underneath the house it is more than 61 meters from any proposed building or  At least 15 meters from the water distribution system exterior drainage facility.  Exception: Single family dwellings with an existing private sewage disposal system may not be connected 3 degrees or grades of waste water: to a new public sewer when no hazard, nuisance or unsanitary condition is evident and when there is no 1. Grey Water (or Area Water) sufficient grade or fall existing to permit proper Waste water with the exception of human wastes drainage flow by gravity to the public sewer. From laundries, wash basins, sinks, tubs, etc. 2. Black Water DAMAGE TO PUBLIC SEWER OR PRIVATE SEWAGE DISPOSAL Water plus solid and liquid human wastes SYSTEM 3. Storm Water  It is unlawful to discharge any ashes, cinders, solids, rags, Rainwater only flammable, poisonous, explosive liquids or gases, oils, grease, and other things whatsoever which would cause CLASSIFICATION OF SEWERS: damage to the public sewer or private disposal system.  Combination Public Sewers  No rain, surface or subsurface waters shall discharge Oldest variety into any excreta drainage system. Carries both storm & sanitary wastes  No cesspool and septic tank effluents, seepage pit or  Storm Sewers under drain system shall be connected to the excreta  Sanitary Sewers building sewer leading to a public sewer main. Carries regular sanitary wastes only  No commercial food waste grinder shall be connected Terminates in a modern sewage disposal plant for to a private or public sewage disposal system treatment Built at a depth of 3 meters (tributaries) SIZE OF SEWER:  The minimum size of any building sewer shall be 2 TYPES OF SANITARY SEWERS: determined on the basis of the total number of fixture 1. Tributary Sewers units drained by such sewer. No building sewer shall be  Termination points of individual units or structures smaller than 150 mm diameter nor less in size than the  Usually round shaped, with diameters between 0.60 to building drain. 1.2 meters  Made of vitrified clay or cement pipes; often installed by INSTALLATION OF SEWER: the curb line, before the street  Building sewers shall be run in practical alignment at a  Normally laid in the Northern or Eastern side of streets uniform slope of not less than 2% or 21 mm/m toward with east-west or north-south orientations the point of disposal.  Exception: When impractical due to depth of street 2. Intercepting Sewers sewer, structural features or to adverse arrangement of  a.k.a. ‘collecting sewers’ building, to obtain a slope of 2%, sewers 102 mm and  Termination points of tributary sewers 152 mm in dia may have a slope of not less than 1%  Placed much lower in the ground, from 4 to 30 meters (10.5 mm/m) and those 203 mm dia and larger may in depth have a slope of not less than 0.5%  Varies in shape (5.3 mm/m) but have a  No building sewer shall be installed diameter or less than 0.6 M from the outer face effective opening of any building foundation, nor less ranging from than 0.3 M below the finish surface 0.60 to 3 meters of the ground.  Sloped at an angle of 1:50 or 2%  Location of building sewer in relation to other services is  Lifting stations are placed at certain intervals and pumps shown below. or sewage ejectors are used to lift the waste; sewers 0.60 m from any building or structure terminate at the disposal plant 15.2 m from water supply wells 15.2 m from streams REQUIREMENTS: 0.30 m from domestic supply pipes Sewers REQUIRED 0.30 m from public water main  Drainage pipes of all buildings shall be connected to the  Building sewer or drainage pipe of clay or materials public sewer. When not available, they shall be which are not approved for use within a building shall connected to an approved private sewage disposal not be laid in the same trench as water pipes unless: system.   the bottom of the water pipe is 0.3M above the MULTIPLE SEEPAGE PITS: top of the sewer pipe (NPC 1208.1.1),  served through a distribution box or shall  the water pipe is placed on a solid shelf excavatedat one be connected in series by means of a side of the common watertight connection. The outlet shall trench with a minimum have a vented leg fitting extending 304.8 horizontal distance of at mm below the inlet fitting least 0.3 m from the sewer or drain pipe (NPC CESSPOOLS 1208.1.2)  a non-watertight lined excavation in the  Water pipes crossing sewer or drainage pipe of clay or groundwhich receives the discharge of materials which are not approved for use within a a sanitary drainage system, designed to building shall be retain the organic matter but laid a minimum of permitting the liquid to seep through 0.3 m clear above the pit bottom and sides the sewer or drain pipe. Water pipe TEMPORARY PERMITS: joint shall be installed not less than 3 meters away from  Temporary expedient pending the construction of a sewer line in both directions. public sewer, so long as it is established that a public sewer will be available in less than 2 years and the soil and ground water conditions are favorable; DISPOSAL FIELDS  As an overflow facility when installed in conjunction  Private sewage with an existing cesspool; disposal system  As a means of sewage disposal for limited, minor, or common in rural areas temporary uses. for structures with large adjacent open fields PRIVIES  Outside Privy- oldest form of disposal of organic AREA: waste. Consists of a vault constructed of  dependent on the required septic tank capacity or concrete for the collection of raw sewage and a estimated sewage flow rate, whichever is greater, and; wooden shelter the type of soil found in the excavation. COMMERCIAL / INDUSTRIAL SPECIAL LIQUID WASTE DISTANCE FROM WATER TABLE: DISPOSAL  No excavation for leach bed shall extend within 1.5 m of REQUIREMENTS: the water table.  When liquid wastes containing excessive amounts of grease, garbage, flammable wastes, sand, or other WITH SEEPAGE PIT: ingredients which may affect the operation of a private  Filter material in the trenches shall terminate 1.5 m sewage disposal system, an interceptor for such waste from pit excavation and the pipe extending from such shall be installed. points to the seepage pit shall be watertight. DISPOSAL:  Waste from interceptors may be discharged to a septic SEEPAGE PITS tank or other primary system or into a separate disposal  a loosely lined excavation in the ground, which receives system. the discharge of a septic tank; designed to permit effluent to seep through pit bottom and sides GENERAL GUIDELINES FOR PRIVATE SEWAGE DISPOSAL SYSTEMS CAPACITY:  Location of Sewage Disposal System  based on the quantity of liquid waste and on the character and porosity of the surrounding soil. SIZE OF SEEPAGE PIT:  Circular in shape with excavated diameter of not less than 2.2 m and to be lined with clay or concrete brick. STRENGTH:  Brick lining shall have a minimum compressive strength of 17225 kPa. Some features of STP:  An aeration system within the tank;  A submersible mixer to mix the waste;  A sludge waste pump that aids in clarifying;  A decanter;  Blowers;  A fully electronic control system, etc. 2 Most Common Types of Municipal Sewage Treatment The Activated Sludge Process  Involves a series of stations where the raw sewage must pass through  First Phase- gets rid of heavy materials with the use of three different filter houses  Second Phase- clarifies the effluent  Third Phase- hardens the sludge and converts it to fertilizers  Produces water with 99-99.5% purity The Trickling Filter Process  a.k.a ‘Percolating or Sprinkling Filter System’  Requires less mechanical elements and less stages  Produces water with 95% purity  Requires a large ground area for its building  STORM DRAINAGE SYSTEM 3. The Natural System  Without using any roof gutters or downspouts  Also when rainwater is collected in cisterns DOWNSPOUTS OR CONDUCTOR Storm Drain Locations PIPES, GUTTERS  Rainwater piping shall not be used as soil, waste and vent pipes.  Downspout and gutter sizes are based upon the maximum depth of rainfall per hour falling upon a given roof area in square meters. An ave. 102 mm/hr rainfall intensity is used around Metro Manila.  Round, square (sized to enclose its equivalent round Roofing Elements to Collect Rainwater: pipe) or rectangular (shall have at least the same cross-  The Gutter sectional area as its equivalent round pipe, except that  Usually located along the entire perimeter of the ratio of its side dimensions shall not exceed 3 to 1) the roof rainwater pipes may be used for downspouts.  Downspouts for high-rise buildings shall be of stronger  The Downspout pipe materials to resist the high hydrostatic pressure,  Located every 8 to 10 meters & at every they shall be installed within a pipe chase, and have no corner of the roof (but, to avoid clogging of intermediate branch from the roof to the ground level pipes, it is best to locate them every 4 to 6 m) ROOF DRAINS  Roof drains shall be equipped with dome-type strainers extending 102 mm above the surface of the roof surface. With a minimum total net inlet area of 1 – ½ times the area of the outlet pipe to which it is connected.  Roof deck strainers shall be approved flat-surface type, with a total net inlet area not less than 2 times the area  The Strainer or Roof Drain of the outlet pipe to which the drain is connected.  Drain designed to receive water collecting on  Roof drains passing through building interiors shall be the surface of a roof and to discharge it into a made watertight by the use of C.I. drain with integrally- downspout. Designed to prevent clogging. cast waterstop ring around the outside of the body and placed at mid-depth of the concrete roof slab and the  The Shoe installation of a clamped suitable flashing material  At the bottom of the roof leader to direct around the drain. rain water towards the nearest catch basin 3 Major Systems ofCollecting Storm Water:  The Catch Basin  Downspouts should terminate in a catch 1. The Independent System basin (can serve more than one a.k.a. ‘the Separate System’ downspout) Brings collected water  Delivers water to the sewers in the street directly to the water via gravity reservoirs  Area-Drain-Catch-Basin: also collects surface water  The Storm Line  Connects to each catch basin  Storm Sewers  Carries only rainwater collected from the storm drain or from the streets  Terminates at natural drainage areas (i.e. lakes, rivers, and water reservoirs)  Require manholes to serve as clean- 2. The Combined System outs and to make sewers accessible for Combines storm water with inspection and repair built at depths of sanitary wastes about 2 to 3 meters; diameter ranging from 0.6 to 1.2 meters  FIRE PROTECTION SYSTEM  Automatic / Sprinkler System  There are two general types of Automatic Sprinkler Systems: Supplying Water for Fire Protection Systems: the Automatic Wet and  The Elevated Water Tank Automatic Dry  The Underground Water Reservoir Types of Fire Protection Systems:  Dry Standpipe System  Wet Standpipe System Spacing of Sprinkler Heads:  Wet Standpipe System with Siamese Connection  Spacing of Sprinkler Heads  Automatic / Sprinkler System  Dry Standpipe System  No longer being utilized in new buildings, provided other systems are employed (otherwise must be installed in  Special Installation Requirements buildings 4 levels or more)  At least one fire department connection on each  The standpipe is a pipe frontage installed in buildings not as part  A master alarm system valve control for all water of the water supply or waste disposal system but supplies other than fire department connections primarily for use as water conveyor in case of fire  Special fire walls between protected areas  How it works: a standpipe is connected to the building  Sloping water proof floors with drains or scupper to exterior (max ht.= 1.20M) for connection to fire carry away waste water department  As much as possible, standpipes should be located in  Types of Sprinkler Heads stairway landings  Upright- used above piping when piping is exposed  Wet Standpipe System  Pendent- projects through a finished  How it works: a piping network (line is directly ceiling when piping is exposed connected to the main water line) connects to all levels of a building (at least 1 standpipe on each level)  Wet standpipes shall be constructed of wrought iron or galvanized steel  The number of wet standpipes shall be determined so that all portions of the building are within 6.00 meters of a nozzle attached to a hose 23 meters long  The minimum diameter for a wet standpipe is 51mm for those less than 15 meters form the fire service connection. For those more than 15 meters from the fire service connection, the minimum diameter is 63mm  Wet Standpipe System with Siamese Connection  How it works: a piping network directly connected to the main water line, connects to all levels of a building; additionally, a Siamese Connection is located outside the building for additional water supply