HydroMax™ Siphonic Drainage Leaders in Siphonic Drainage

Topics Covered Brief History of Siphonic Drainage General Principles of Gravity Rainwater Drainage Principles of Siphonic Drainage Benefits and applications of Siphonic Drainage Installation and Maintenance Here are today’s learning aims. We shall start by looking at gravity rainwater and siphonic rainwater systems side by side to discover the significant differences. We shall then move on to discuss the principles of siphonic drainage in detail and then in to the benefits and applications of such a system. Finally we shall discuss the salient design elements of the such a system, the standards that dictate these, how a system is designed, installed, tested and maintained.

Introduction to Siphonic Drainage Prior to March 2007, there were no comprehensive product and design standards for siphonic drainage. As such siphonic drainage was promoted by suppliers in different formats with various slants aimed at their own offerings The HydroMax focus is on offering high quality, sustainable products with highly accurate and user friendly design software Our approach is to dispel the “smoke and mirrors” educate how they work in accordance with the current British and/or American Standards Technical Support to Design Engineers and Registered Installers As an introduction, we would like to explain a bit about the history of siphonic drainage in this country. Prior to March 2007 there were no comprehensive product and design standards for siphonic drainage. The publication of BS 8490 – the current ruling British Standard for siphonic drainage – changed this. Previously, siphonic drainage was promoted by suppliers in different formats with various slants aimed at their own offerings. BS 8490 can be used dispel the “smoke and mirrors” previously employed in the market place and clarify how siphonic roof drainage systems work. We will try to show how it can work for you through the education provided during this presentation. As an aide to control over quality design and supply, we suggest that you should seek to use manufacturers with a Technical Team to provide support to the both the Design Teams and Registered Installers.

Siphonic Drainage – Brief History Concept invented in Finland by Olavi Ebling in late 1960’s First major installation in Sweden in 1972. Unregulated Industry Grew through 1980’s UK Government Commissioned Research during the 1990’s (Refer HR Wallingford SR 463 & SR 473) European Standard BS EN 12056-3 introduced in 2000 (1st Standard to include a section for Siphonic drains) 2005 – ASME A112.6.9 Siphonic Drain Test issued in USA 2006 – Singapore Standard SS 525 includes siphonic drainage 2007 – Comprehensive Siphonic Drainage Standards published in UK and USA (BS 8490 and APSE 45) Siphonic drainage started off as a Concept invented in Finland by Olavi Ebling in late 1960’s First major installation in Sweden in 1972. An Unregulated Industry Grew through 1980’s which led to specifiers becoming uncertain as to how siphonic should be specified and utilised. This led to UK Government Commissioned Research by HR Wallingford during the 1990’s (the HR stands for Hydraulic Research) HR Wallingford reports SR 463 & SR 473 were studies on performance of siphonic systems on flat roofs and in gutters that you can refer to but technical advances and the advent of BS 8490 makes them a little superfluous. European Standard BS EN 12056-3 introduced in 2000 which was the first standard to include a section for Siphonic drains. BS 8490 was first published in March 2007 – this is Comprehensive Siphonic Drainage Standard covering all aspects of design rainfall rate selection, design, hydraulic parameters to be met, pipe specifications, testing and maintenance.

What is HydroMax™ Siphonic Roof Drainage? HydroMax™ is an innovative solution which utilises the power of a natural siphon to create a high-performance roof drainage solution. So what is Siphonic Roof Drainage? Siphonic Drainage is an innovative solution which utilises the power of water accelerating as it falls down the vertical downpipe to generate a naturally induced siphon which in turn creates a high-performance roof drainage solution .

HydroMax™ offers cost savings normally ranging from Why use HydroMax™ Siphonic Roof Drainage? HydroMax™ is an Engineered Solution which provides many Technical Benefits HydroMax™ offers cost savings normally ranging from 25% to 45%! Why would you use a Siphonic Roof Drainage solution? Siphonic Drainage is an Engineered Solution which provides many technical benefits which we will provide examples of during this presentation It is also one of these rare products that in addition to technical benefits can also offer cost savings In suitable project types these savings normally range from 25% to 45%!

What is wrong with Traditional Gravity Drainage Systems? Traditional Gravity drainage systems work but they are inefficient and have a number of factors restricting performance. Before explaining siphonic drainage lets explore What is wrong with Traditional Gravity Drainage Systems? Traditional Gravity drainage systems work - as they have done for centuries However, they are inefficient with a number of factors restricting their performance.

Restrictive Factors of Gravity Drainage The water flow-rate is dictated by the gradient available (this gradient also restricts the distance a pipe can travel). Multiple rainwater pipes in locations largely dictated by the gravity hydraulics rather than design team choice. Gravity drains require ⅔ air to transport ⅓ water. Vortex formation within vertical gravity pipes results in the water being transported in an inefficient spiral motion rather than straight through the pipe. The driving force is only the depth of ponding or ‘head’ of water above the roof drain. 1. The slope to which the pipework is installed at dictates how much water the pipe can transport. The greater the gradient the higher the flow. But the slope also limits how far the pipe can travel before it encroaches through the ceiling or roof space. 2. Because the slope limits how far the pipes can travel, the result is that you have many Rainwater downpipes sited in locations which have been dictated by the hydraulics rather than design team or client’s choice. 3. Gravity drains require ⅔ air to transport ⅓ water resulting in large diameter pipes. 4. The vortex that you would see at a bath or sink plughole happens at all gravity drains. The flow is an inefficient spiral motion rather than straight flow into the pipes below the drain. 5. The only driving force for the system is the depth of water on the roof forcing water into the roof drain. The deeper the water the greater flow into the pipe below. As a rule of thumb, given equal inflows, a siphonic drain will have approximately half the ponding of a gravity drain.

Gravity 10” Drain – Depth = 7.3” to Discharge 1500 GPM “High Performance” Gravity Drain (from Manufacturers web-site) Gravity 10” Drain – Depth = 7.3” to Discharge 1500 GPM (250mm Drain – Depth = 185mm to Discharge 95 l/s)

125mm Drain – Depth = 95mm to Discharge 95 l/s HydroMax 125mm (5”) Drain Equivalent Flow (95 l/s – 1500GPM) Half the Diameter Half the ponding depth of the Gravity drain 125mm Drain – Depth = 95mm to Discharge 95 l/s

Vertical Gravity pipes run ‘full’ at only 1/3 water ⅓ water in annular flow ⅔ air core Vertical Gravity pipes run ‘full’ at only 1/3 water With the 1/3 water in annular flow where the water adheres to the inner pipe wall with an air core down the middle.

run ‘full’ at only 2/3 water Horizontal (Sloping) Gravity pipes run ‘full’ at only 2/3 water Horizontal Gravity pipes are not flat – they need a slope to allow water to flow These pipes run ‘full’ at only 2/3 water with the air required for flow to occur being above the water

Typical Traditional Gravity Drainage System Multiple Downpipes As you will see, this is typical warehouse type building with two eaves and a single valley configuration for the roof. The traditional design results in multiple rainwater pipes in locations dictated by the hydraulics. The valley also has numerous rainwater pipes dropping inside the building taking up valuable building space. The whole system is served by an extensive network of below ground drainage. You will also note that the valley is served by drainage which is running under the building floor. If anything ever went wrong with this drain line you would have serious internal flooding and any rectification would incur serious disruption problems. Drainage under Building Floor Extensive Underground Drainage Sloping Underground Drainage makes for difficult routing to attenuation/harvesting

Principles of Gravity Drainage Vortex motion A large amount of Air is required to move a small amount of water. Extremely Inefficient So to summarise Gravity drainage, we have Inefficient vortex flow into the roof drain. This vortex pulls a core of air into the pipes to allow the water to flow with the ratio being only 1/3 water to 2/3 air in vertical pipes which leads to large diameter pipes. It really is an inefficient use of the piping system. Annular Flow Water adheres to pipe wall Central Air Core

Siphonic Drainage Why is HydroMax™ different from gravity drainage? No Air! We will now move on to explain how siphonic drainage works and see how it is different from gravity drainage? Firstly siphonic drainage eliminates air ingress to the system allowing pipes to flow 100% full of water Pipes run 100% full bore

Principles of HydroMax™ Siphonic Drainage The Siphonic Roof Drain eliminates air entering the pipe promoting water filled pipework The full bore of the pipe work carries the rainwater Water, without air, accelerates down the vertical downpipe, creating negative pressure and naturally generating a high performance siphonic flow The full height of the building provides the energy for this highly efficient Rainwater Drainage Solution The main principles of siphonic drainage are First of all the siphonic roof drain is design to prevent vortex formation and also prevent air entering the piping system. This allows the full bore of the pipes to carry the rainwater. As water without air accelerates down the vertical downpipe, it creates negative pressure and naturally generates a high performance siphonic flow Unlike gravity systems we now use the full height of the building to provide the energy for this highly efficient Rainwater Drainage Solution

Siphonic Drainage - How it works The inducer on the roof drain prevents air ingress and so Rainwater falling down the vertical pipe accelerates, creating negative pressure PAtmos - gh The inducer on the roof drain stops vortex formation and prevents air ingress and so the water fills the full bore of the rainwater pipe The rainwater falling down the vertical pipe accelerates which naturally creates negative pressure There are no moving component parts within a siphonic system – it is simply natural hydraulics that make it function

Siphonic Drainage - How it works PAtmos - gh As we have said it is the full height of the vertical displacement that generates the siphonic action So More Height = Greater Negative pressure More Height = Greater Negative pressure

Siphonic Drainage - How it works PAtmos - gh Greater Negative Pressure = Higher Flow Rates The full height of the building provides the energy for this highly efficient Rainwater Drainage Solution And Greater Negative Pressure = Higher Flow Rates

Siphonic Drainage - How it works HydroMax Siphonic Systems are self-draining therefore the pipes are empty before a rainfall event Roof or Gutter Tail-pipes Horizontal collector pipe Downpipe Discharge HydroMax Roof Drain This system has 3 roof drains connected to a horizontal carrier pipe with a single downpipe at the end of the run. This is the same configuration as used on the video coming up shortly. Siphonic Systems are self-draining therefore the pipes are empty before a rainfall event

Horizontal Collector Pipe HydroMax System with Tailpipes primed HydroMax Roof Drain Roof Pressure Tail-pipes Horizontal Collector Pipe Drop pipe Discharge

Priming of Main Pipe Work Stage 1 - Wavy or Gravity flow Air above water Gravity flow in pipework The first flow pattern is Wavy or Gravity flow where water flows along the bottom of the pipe with air flowing above it. The siphonic pipe will be of significantly smaller diameter and be installed with no gradient – it is completely flat. This, combined with the fact that further air entry is prevented by the roof drain, leads to the water quickly filling the pipe. We want this pipe to fill as quickly as possible because when it if full and the water filling the whole bore falls down the vertical pipe – it accelerates creating negative pressure. The generation of negative pressure accelerates the water and moves us onto the next flow pattern.

Priming of Main Pipe Work Stage 2 - Plug flow Plug of water filling whole pipe at high velocities which achieves self-cleansing. Air pockets driven down pipework This is termed Plug flow because the acceleration down the vertical has created of negative pressure pulls the water into plugs filling the whole of the pipe. This plug also pushes the air in front of it down and out of the piping system. Because the water fills the entire bore and is moving at high velocities, self-cleaning is achieved. This makes this flow pattern the most important in a siphonic system. Manufacturer’s and University tests have shown that self-cleansing is achieved at between 10% to 15% of the design rainfall rate therefore regular self-cleansing of the system takes place. As an example to demonstrate how little rain is required to achieve cleaning, lets assume a project has a design rainfall rate of 0.042 litres per second per metre squared or 150mm/hr, self cleaning would be attained at rainfall rates of between 15mm/hr to 22mm/hr – to put this into perspective, this equates to just one quarter of a mm of rainfall per minute. If the rainfall intensity continues to increase we will move on to the next flow pattern. Tests have shown that self-cleansing can be achieved at as low as 10% to 15% of the design rainfall rate.

Priming of Main Pipe Work Stage 3 - Bubble flow Water filling whole pipe Air bubbles in suspension carried at high velocity Bubble flow takes place when there is insufficient flow to be fully primed and there is still a little air either entering from the drain or not purged from the system. As with the Plug flow this continues to be self cleaning.

Priming of Main Pipe Work Stage 4 - Full-bore flow No more air entry – Air within Pipe now Fully Purged When the rainfall rate is upwards of between 60% and 70% of the design rainfall rate, the system will be filled and be running in full-bore flow literally sucking the rainwater from the roof. Once the rain storm starts to abate, air will be admitted through the roof drain into the piping system. The above noted flow patterns will reverse in a process known as de-priming. This takes place seamlessly in a smooth controlled manner which mirrors the storm profile.   Furthermore, if the rainfall rate increases again, prime is quickly re-established and the siphonic flow is naturally formed providing a highly efficient Engineered Roof Drainage System. Water filling whole pipe

Fully Primed HydroMax System HydroMax Roof Drain Negative Pressure Roof or Gutter Tail-pipes Horizontal Carrier Pipe The full height of the building provides the energy for this highly efficient Rainwater Drainage Solution Downpipe Now in its fully primed state, the negative pressure in the system has increased as we are utilising the full height of the building to draw water off the roof. Discharge

Principles of HydroMax™ Siphonic Eliminate Air Ingress Pipes run Full-Bore with Water Building Height provides energy for High Self-Cleansing Velocities Extremely Efficient So to summarise the principles of our Terrain HydroMax siphonic drainage, First of all the siphonic roof drain stops vortex formation and prevents air ingress This allows the pipes to run full bore with water and with negative pressure being generated through the water column accelerating down the vertical pipe, the whole height of the building provides the energy to suck the water from the roof. As the pipework carrying capacity is maximised with full bore flow and high velocities with self cleaning properties you really do have an extremely efficient roof drainage solution.

Siphonic Roof Drainage Video HydroMax™ Siphonic Roof Drainage Video Click Here We now have a couple of videos showing how siphonic systems operate through the priming process with the second video simulating a roof which has not been maintained.

HydroMax™ Simulation of Non-Maintained Roof Click Here We now have a couple of videos showing how siphonic systems operate through the priming process with the second video simulating a roof which has not been maintained.

Siphonic Roof Drainage System High Performance Roof Drains No Drainage Under Building Flexible, Downpipe Positioning Now, here is the same warehouse that we saw earlier but this time with a Siphonic Roof Drainage system. You can have fewer roof penetrations because less drains may be used due to the HydroMax siphonic drains having a much higher capacity than gravity drains The pipes run horizontally to fewer downpipes which results in significantly less below ground drainage This reduction in underground drainage is where the cost savings come from. No drainage below the building floor. There will be significantly fewer Rainwater pipes Rainwater pipes will be in the locations as chosen by the design team. Easy routing to rainwater attenuation or harvesting Significant Reduction in Underground Drainage Route to Harvesting or Attenuation

System Comparison Traditional HydroMax Gravity Siphonic air core water in annular flow water No Air air core water water Looking at the two systems side by side. Going back to the vertical section of a gravity rainwater system, we can begin to see the inefficiency. We have to design the system to account for air flow as it is this flow of air that allows the water to move in the pipe section ( the air is entrained by the movement of water and replaces the volume of water moved). With a siphonic rainwater system it is working at its most efficient at the point that it is full i.e. 100% full of water with all air eradicated. You can also begin to see another advantage of using a siphonic system in that we can deliver similar flow rates with smaller pipes and fittings

Traditional Gravity Solution 530 metres Pipework Diameters 160mm to 450mm 60m 100m HydroMax Siphonic Scheme 360 metres HDPE Pipework Diameters 56mm to 200mm Now seeing the two solutions side by side we can see at top left on the gravity scheme we have 530 metres Pipework The Diameters are 160mm on the vertical downpipes going up to 450mm on the underground collection runs Now looking at the siphonic system at bottom right we have only 360 metres HDPE Pipework - significantly less than the gravity scheme – but equally important is the Pipe Diameters that range from 56mm on tailpipes from the drains up to a maximum of 200mm on the downpipe

HydroMax System Termination Manhole or Catch Pit to have Grate Cover Note: British Standard BS 8490 states the size of free area for the Grate should be twice cross sectional area of siphonic pipe. American ASPE Technical Design Standard 45 does not dictate the size of vented area. One of the most common means of terminating the siphonic system is to break the siphonic action at the first manhole outside the building. In this case the manhole should be fitted with a grated cover to provide ventilation – BS 8490 calls for open area to be no less than twice the cross sectional area of the siphonic pipe. This open area does two things. Firstly it allows the air to be purged from the system during the priming process. Secondly, if the underground drainage ever surcharges, it allows the water to escape from the open grate allowing the roof to drain Siphonic pipework should enter manhole chamber above the drain invert and be clear of any standing water to ensure free discharge

HydroMax Siphonic System Termination Vertical Siphonic Pipe Important: Below Grade Drain must be vented and sized to take the volume of discharge under Gravity flow conditions. Do not size to match siphonic Pipe diameter. Offset (if required) to line up with below grade pipe Flex-Seal flexible, expansion coupling

HydroMax Siphonic System Termination Important: If siphonic drainage is utilised to drain part way down a high rise building – A siphon break point must be adequately vented to atmosphere at the point of transition to gravity flow.

HydroMax Siphonic System Termination Ventilated to Atmosphere Siphonic flow Break to Gravity flow Recommended Vent size being Two-Thirds Gravity Pipe size (two-thirds air to one third water in the gravity pipe)

Suitable Projects for Siphonic Drainage Retail Chains We will now run through a list of suitable project types. As a rule of thumb we would normally say that you can get technical benefits from a roof area of 1000m2 and cost savings will be achieved at 2500m2 and above The bigger the roof the bigger the savings. The first category of project types is Retail chains – siphonic drainage has been extensively used on this type of building since the early 1990’s and is regarded as being the normal roof drainage system for this type of building.

Suitable Projects for Siphonic Drainage Stadia Royal Ascot Racecourse Ricoh Stadium and Arena, Coventry Stadium Projects The Stadium of Light on the left had one quarter of the whole roof area drained to a single drainage point. The Coventry Stadium and Arena on the right used only 6 rainwater pipes to drain the whole roof. Stadium of Light, Sunderland

Suitable Projects for Siphonic Drainage Dundrum Retail Shopping Malls with multi-level Car Parks 313 Orchard Road, Singapore This is a large town centre retail development. The landlord specified siphonic roof drainage so that all rainwater pipes were routed to landlord areas thus freeing up lettable tenant space to increase the rental earnings. A Siphonic Roof Drainage system was also used to drain the top level of the multi-storey car park shown on the left third of the site.

Suitable Projects for Siphonic Drainage Commercial Office Buildings Accident Fund, Lansing This is a large town centre retail development. The landlord specified siphonic roof drainage so that all rainwater pipes were routed to landlord areas thus freeing up lettable tenant space to increase the rental earnings. A Siphonic Roof Drainage system was also used to drain the top level of the multi-storey car park shown on the left third of the site. E-Tek Flagship Trinidad Stryker HQ, Newbury

Suitable Projects for Siphonic Drainage Accommodation/Hotels/Prisons Student Accommodation, Wembley This is a large town centre retail development. The landlord specified siphonic roof drainage so that all rainwater pipes were routed to landlord areas thus freeing up lettable tenant space to increase the rental earnings. A Siphonic Roof Drainage system was also used to drain the top level of the multi-storey car park shown on the left third of the site. Johnstone County Detention Center Ibis Hotel, Singapore

Suitable Projects for Siphonic Drainage Hospitals Forest Park Medical Center, Dallas This is a large town centre retail development. The landlord specified siphonic roof drainage so that all rainwater pipes were routed to landlord areas thus freeing up lettable tenant space to increase the rental earnings. A Siphonic Roof Drainage system was also used to drain the top level of the multi-storey car park shown on the left third of the site. Mercy Hospital, Des Moines, IA

Suitable Projects for Siphonic Drainage Apartment Blocks Apartment blocks can benefit from using siphonic drainage because you can route the downpipes to service cores Podium decks can benefit where there is sufficient vertical displacement from podium deck to the termination point Podium Decks

Suitable Projects for Siphonic Drainage This is the award winning Scottish Parliament building. The Terrain-HydroMax™ system was selected because of the technical ability to drain complex roofs through unobtrusive small diameter pipes. Green Roofs

Suitable Projects for Siphonic Drainage Siphonic Drains installed at waterproofing membrane level On green roofs careful planning is required but the roof drains will always be sited at the waterproof membrane level which will be under the egg crate soil retaining system Concerns about the possibility of soil ingress to the siphonic system are nullified because green roof systems are designed to retain the soil – if the soil was permitted to go down the drain then there would be no green roof As such this is not an issue Green Roofs

Suitable Projects for Siphonic Drainage Airports We have used Siphonic Roof Drainage systems for small domestic airports and large international airports. Gimhae South Korea

Suitable Projects for Siphonic Drainage Warehousing & Distribution Centres Warehousing and distribution centres normally will use siphonic drainage systems due to the vast roof areas and associated technical and cost saving benefits 110,000m² for Tesco

Suitable Projects for Siphonic Drainage Manufacturing Plants Our Siphonic Roof Drainage system’s have been used on numerous hi-tech electronics and Pharmaceutical projects.

Suitable Projects for Siphonic Drainage Flagship Projects This is the award winning Scottish Parliament building. The Terrain-HydroMax™ system was selected because of the technical ability to drain complex roofs through unobtrusive small diameter pipes. Scottish Parliament

Masdar City MIST 1B, Abu Dhabi Suitable Projects for Siphonic Drainage Flagship Projects This is the award winning Scottish Parliament building. The Terrain-HydroMax™ system was selected because of the technical ability to drain complex roofs through unobtrusive small diameter pipes. Masdar City MIST 1B, Abu Dhabi

HydroMax Siphonic Products 50mm Balcony Siphonic Roof Drain This is a special drain for multi floor balcony drainage. The drain has a built in Anti-Backflow device. Flow Rate Max. = 1.5 l/s (Litres per Second) Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

HydroMax Siphonic Products 50mm Terrace Siphonic Roof Drain Flow Rate Min. = 1.5 l/s (Litres per Second) up to Max. = 25 l/s Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

HydroMax Siphonic Products 75mm Siphonic Roof Drain Our Metric series of drains come in a range of models for compatibility with all roof types Flow Rate Min. = 1.5 l/s (Litres per Second) up to Max. = 25 l/s Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

HydroMax Siphonic Products 75mm Siphonic Overflow Roof Drain Our Metric series of Overflow drains come in a range of models for compatibility with all roof types Flow Rate Min. = 1.5 l/s (Litres per Second) up to Max. = 25 l/s Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

HydroMax Siphonic Products 125mm Siphonic Roof Drain Our Metric series of drains come in a range of models for compatibility with all roof types Flow Rate Min. = 10 l/s (Litres per Second) up to Max. = 100 l/s Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

Range of Accessories for Our Metric Series of Drains HydroMax Siphonic Products Range of Accessories for Our Metric Series of Drains Leafguards Gravel Guards Car Park Drains Bespoke Accessories Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

Wade-HydroMax Siphonic Products 3” Siphonic Roof Drain Our North American series of drains have all been tested to ASME 112.6.9:2005 – IAPMO certified (file number 5305) Flow Rate Min. = 23 GPM (Gallons per Minute ) up to Max. = 415 GPM Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

Wade-HydroMax Siphonic Products 4” Siphonic Roof Drain Our North American series of drains have all been tested to ASME 112.6.9:2005 – IAPMO certified (file number 5305) Flow Rate Min. = 75 GPM (Gallons per Minute ) up to Max. = 750 GPM Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

Wade-HydroMax Siphonic Products 5” Siphonic Roof Drain Our North American series of drains have all been tested to ASME 112.6.9:2005 – IAPMO certified (file number 5305) Flow Rate Min. = 120 GPM (Gallons per Minute ) up to Max. = 1300 GPM Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

Wade-HydroMax Siphonic Products 6” Siphonic Roof Drain Our North American series of drains have all been tested to ASME 112.6.9:2005 – IAPMO certified (file number 5305) Flow Rate Min. = 160 GPM (Gallons per Minute ) up to Max. = 1800 GPM Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s.

Wade-HydroMax Siphonic Products 3”, 4”, 5” and 6” Siphonic Roof Overflow Drain Our North American series of drains have all been tested to ASME 112.6.9:2005 – IAPMO certified (file number 5305) Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s. C.I. No-Hub Outlet K factor Minimum GPM Inflow Maximum GPM Inflow 3” 0.12 23 415 4” 0.08 75 750 5” 0.04 120 1300 6” 160 1800

Wade-HydroMax Siphonic Products 3”, 4”, 5” and 6” Drain Accessories Leafguards, Debris Guards, Underdeck Clamps and Bearing Pans are available for all drains. Our 3” and 4” Drains are available as Podium Deck Drains Moving on to the systems component parts The special design of the roof drain eliminates air ingress into the piping system which is empty before a storm event. The fins that protrude from the inducer prevent vortex formation and routes the water directly into the pipe below. As the water level on the roof or gutter reaches the flat inducer plate, air is effectively sealed off and cannot enter the pipe below. The drains inflow is calculated by taking the roof drain catchment area and multiplying by the design rainfall rate (which will vary according to the project location and category of risk specified by the design team) 75mm drains can be used for inflows ranging from 1.5l/s up to a maximum of 25l/s. Drain shown with Debris Guard

HydroMax Siphonic Drain Benefits High Performance Versatile and Compatible with any Roof Compact for installation in gutters/scuppers Anti Tamper Fastening of one-piece Inducer Proven track record of Low Maintenance Siphonic drain benefits include Significantly higher flow rates than gravity drains They are manufactured in a range of materials to allow compatibility with all roof types Compact for installation into gutters – Terrain HydroMax drains can be installed in gutters with only a 230mm wide sole As the inducer/air baffle is critical to the operation of the siphonic system, you should specify that the drains be fitted with anti-tamper fastening of the inducer/air baffle

HydroMax™ HDPE Siphonic System The Terrain-HydroMax™ HDPE is of the highest quality and pressure rating available. Using PN 4 rated PE 80 on diameters up to and including 160mm, the Terrain-HydroMax™ pipework utilises PN 5, PE 100 on the larger diameter pipes. All securely fastened to the engineered rail fastening system which not only supports the pipework, it also prevents lateral movement and controls thermal movement. Pre-Fabricated in Factory Controlled Conditions with Engineered Rail Fastening System

HydroMax™ Siphonic System 60,000m² Roof Only 4 Rainwater Downpipes draining the Main Roof This is a large distribution warehouse which was drained using only 4 rainwater pipes. A series of roof drains were collected at high level into each of these 4 pipes and the rainwater pipes were routed into convenient drop locations at the four corners.

HydroMax™ Siphonic System HydroMax™ Collector Pipe at High Level Here is the internal shot. Several roof drains connect into the high level horizontal carrier pipe. The pipe runs unobtrusively at high level. If this was a traditional gravity scheme, there would be rainwater pipes on every column which would interfere with the loading docks and the door mechanisms where the pipes would have to offset to pass over the pad foundation. In addition to saving money on the project Terrain HydroMax™ provides a huge benefit technically and maximises the space available.

HydroMax™ Siphonic System Level, Small Diameter, Pipes Makes for Easy Co-ordination with structure and services This is an example of how easy it is to co-ordinate the pipework in congested ceiling voids.

HydroMax™ Siphonic System HydroMax™ Pipework Installed Absolutely Flat Level at High level The benefit is clear to see in this photograph with the pipework being able to run flat with small diameter pipes from one end of the car park to convenient downpipe location This picture shows the pipes running below the beams but because the pipework runs absolutely level, the pipe can run through beams as we can hit the centre line of each beam

Development of Key Standards & Codes BS EN 12056-3:2000 (includes Siphonic Drain Test) ASME 112.6.9:2005 (Siphonic Drain Test) ASPE Technical Design Standard 45:2007 (Design, Installation & Product Standard) BS 8490:2007 (Design, Installation & Product Test Standard) The publication of key standards started in 2000 First came BS EN 12056-3 in 2000 which was the first standard to incorporate a section on siphonic drainage and includes a Siphonic Drain product Test Then came the American ASME 112.6.9 published in 2005 – this is a dedicated siphonic roof drain product Test In January 2007, the American Society of Plumbing Engineers published ASPE Technical Design Standard 45 which was the first comprehensive design, pipe specification, installation, test and maintenance standard. For the UK market, the important standard is BS 8490 published in March 2007 – Like ASPE 45 this is a fully comprehensive Design, Installation & Product Test Standard with the drain test superseding BS EN 12056 BS 8490 does cross refer to BS EN 12056-3:2000 for the calculation of design rainfall rate

Development of HydroMax™ Consultation with HR Wallingford (previously commissioned by UK Government to study siphonic drainage) ensured our offering progressed the technology above competitors systems HydroTechnic™ hydraulic calculations report extreme conditions giving high accuracy (other systems report average hydraulic conditions) Independently tested by Hydraulic Research Centre Wallingford (HRW) for compliance with BS EN 12056-3:2000 Independently tested to ASME 112.6.9 (IAPMO File #5305) Full Compliance with current SS525, BS 8490:2007 & ASPE 45 100% Success Rate Terrain-HydroMax™ and HydroTechnic™ was developed by a team with over 35 years of experience in siphonic drainage which brought inherent knowledge of all aspects of design, installation AND maintenance. The Development of Terrain-HydroMax™ and HydroTechnic™ Design Software Program was induced by the introduction of BS EN 12056-3 in 2000. Consultation with HR Wallingford ensured the Terrain HydroMax™ offering progressed the technology above competitors systems HydroTechnic™ hydraulic calculations report extreme conditions to give accuracy confirmed as “unsurpassed” during the testing other systems report average hydraulic conditions leading to inaccuracy

Development of HydroMax™ Full Compliance with SS525:2006 Full Compliance with BS 8490:2007 Full Compliance with ASPE Design & Engineering Standard 45 100% Success Rate Terrain-HydroMax™ and HydroTechnic™ was developed by a team with over 35 years of experience in siphonic drainage which brought inherent knowledge of all aspects of design, installation AND maintenance. The Development of Terrain-HydroMax™ and HydroTechnic™ Design Software Program was induced by the introduction of BS EN 12056-3 in 2000. Consultation with HR Wallingford ensured the Terrain HydroMax™ offering progressed the technology above competitors systems HydroTechnic™ hydraulic calculations report extreme conditions to give accuracy confirmed as “unsurpassed” during the testing other systems report average hydraulic conditions leading to inaccuracy

Primary and Overflow Systems Using HydroMax Overflow System can offer the same technical and commercial benefits obtained using the HydroMax™ Primary Drains Primary Roof Drains installed at roof level or at gutter sole level Drains direct to underground drainage Overflow Roof Drain Inlet raised to 50mm above gutter sole. Drains to Atmosphere often at high level or to walkways or car parks Must not connect to Primary System (as this would normally be a vent) 50mm Raised Inlet to Drain Here is an example of a basic overflow system whereby an outlet on the secondary system is at raised height within a gutter so in normal operation the primary system drains away but in abnormal operation the overflow system is brought in to play

Maintenance by Design Primary Drain Overflow Drain Regional Options: Raised Inducer Level Roof Level Installation should be carried out in accordance with BS 8490 and manufacturers recommended installation instructions. It is normally the case that the roofers install the outlets and seal the roof and then the M&E company installs the rainwater system afterwards. Outlets should be approved and independently tested to BS 8490. The normal testing regimes apply with an air test and possibly a flood test performed to check for leaking pipes/joints. The flood test is a static head test as a dynamic test would require significant volumes of water to be constantly flooded on to the roof area! As there are no moving parts on a siphonic system, maintenance is just an inspection excersise. Care must be taken to make sure that the outlets are free of debris or covers (such as plastic bags) and that if installed in to gutters then the gutter maintenance regime is upheld (although from the video we saw that the heads and the system can cope with large amounts of leaf/dust ingress!) Regional Options: Dry Season Covers for Gulf Region 73 Page 73

Siphonic Drainage Analytical Design Program HydroMax™ provides the following: Web based HydroTechnic™ program for easy Technical Support Fast Accurate Calculations in full compliance with SS525, BS 8490 & ASPE 45 Advanced Edit Functions to accommodate on-site changes Program Generation of Pre-Fabrication Drawings (Eliminates risk of human interface errors) Exports data in electronic format for O & M files All siphonic systems will be calculated using a hydraulic Design calculation Program. Calculations can be made by hand but are too time consuming and so renders this method impractical. In respect of what you should specify – you should seek suppliers to have Web based program for easy Technical Support Fast Accurate Calculations in full compliance with BS 8490 – this is very important Advanced Edit Functions to accommodate site changes Program Generation of Pre-Fabrication Drawings (this ensures accurate supply in accordance with the calculated hydraulics as there is no leeway for installers to change sections of pipework) Most projects have electronic format O & M manuals – as such you need your supplier to be able to provide the calculation data in electronic format

Siphonic Drainage Analytical Design Program Metric Version Before using the calculation program the designer has to Obtain the design rainfall intensity from the design team calculate the rainfall inflows to each drain (catchment area x rainfall rate) Identify the required pipe routes (normally determined in conjunction with the architect and with a view to save on below ground drainage) Then draw the required pipe routing into the calculation program and perform hydraulic calculation Please note it is important that the design software has all parameters in accordance with BS 8490 and clearly identifies to the designer when all these parameters are met. In this case you can see on the right hand side the various parameters required and the GREEN PASS indicating conformity. Following calculation of rainfall inflows and determination of required pipe routing, the Design Engineer ‘Draws’ the piping system into the calculation program USA Version ft/in and GPM

Pipe diameters are edited to find the optimum solution Our advanced program will allow the design engineer to scrutinise the system and change pipe diameters to optimise the system while still clearly displaying conformity with BS 8490. Pipe diameters are edited to find the optimum solution USA Version Metric Version

Key Advantages with HydroMax™ Drains independently tested to: BS 8490:2007 ASME 112.6.9:2005 Designs to BS 8490 or ASPE 45 Independently tested HydroTechnic™ design software (confirmed to have “unsurpassed accuracy”) Range of High Performance Roof Drains (Outlets) HDPE Pipes to EN 1519 (not for North American Market) Seek drains which have passed independent testing to BS 8490:2007 And ASME 112.6.9:2005 As the whole operation is dependent on the hydraulic calculation seek independently tested design software which reports extreme hydraulic conditions and not averages For sustainable supply with reduced transportation we provide UK manufacture of roof drains and UK manufactured pipes – no other company produces PE pipes to EN 1519 in the UK.

Key Advantages for Building Owners High Performance, Self-Cleansing Roof Drainage System Fewer Rainwater Downpipes routed to convenient positions providing an increased and flexible use of floor space Proven Record of Low Maintenance Elimination of underground drainage, manholes, etc. within the building footprint Finishing up we will summarise the key advantages to the various parties starting with the Building Owner Siphonic drainage provides High Performance, Self-Cleansing Roof Drainage System Elimination of underground drainage, manholes, etc. under the footprint of the building Fewer Rainwater Downpipes are required and those that are required are routed to convenient positions providing an increased and flexible use of floor space

Key Advantages for the Design Team Smaller diameter horizontal pipework installed level An Engineered Solution allowing choice of discharge locations Flexible Pipe routing with easy co-ordination of services Rainwater Management - HydroMax™ can route pipework to attenuation/rainwater harvesting. For the design team There is smaller diameter horizontal pipework installed level making it easier to accommodate in tight spaces It is an Engineered Solution allowing control over discharge locations freeing up building space Flexible Pipe routing with easy co-ordination of services – as the pipes are level it is easier to co-ordinate and now you can zone your rainwater drainage pipe instead of having it slope and clash with everything Rainwater Management - Siphonic Drainage is by far the best solution to route pipework to your rainwater harvesting tanks or to attenuation

Key Advantages for the Main Contractor Improved Construction Build Program Significant Cost Savings A dry building envelope is attained at an early stage of construction allowing fit-out works to proceed earlier Less Trench work for below ground drainage saving excavation, soil treatment, pipe laying, back fill compaction, etc. Less below ground drainage and associated trenchwork together with Less pipes and smaller diameters reduce program build time. The elimination of underground drainage realises cost savings – please note that above ground drainage and below ground drainage are normally handled by different design team members and priced within different packages. When doing cost comparisons it is essential to include the below ground drainage because if you just compare the above ground options then you have taken no account in the cost savings from reductions in the underground system. Pre-fabrication of pipework can also help save program time and achieve a dry building envelope at an early stage allowing fit-out works to progress earlier.

Engineers Training Day – Topics Covered Key Aspects of BS 8490:2007/ASPE 45/SS 525 Hydraulic Parameters Piping Layout Design (do’s and don'ts) Hands-on HydroTechnic training Understanding how to Edit Systems within HydroTechnic™ to cater for design or onsite changes Specification Writing Training days are a very good way of learning more about design and specification of siphonic drainage Topics which should be covered include: Key Aspects of BS 8490:2007 – the current ruling standard for siphonic drainage Hydraulic Parameters within BS 8490 and the reasons for these parameters Piping Layout Design (do’s and don’ts) Specification Writing

Information Requirements For HydroMax to Provide Concept Designs Design Rainfall Rate Roof Plan Drawings (AutoCAD) Floor Plan Drawings (AutoCAD) Sections/Elevation Drawings (AutoCAD) Underground drainage Connections Attenuation or Rainwater Harvesting Requirements Gutter Profile (to allow compatibility checks) Specification (we can provide CSI or R10 type spec.) If you are looking for a concept design for your building the following information is required by the siphonic drainage designer Design Rainfall Rate Roof Plan Drawings (AutoCAD increase speed and accuracy) Floor Plan Drawings (AutoCAD) Sections/Elevation Drawings (AutoCAD) – as the vertical displacement is the energy to create the siphonic action these drawing are essential Underground drainage Connections – this is sometimes chicken and egg – we can assist with the determination of locations required Attenuation or Rainwater Harvesting Requirements Gutter Profile (to allow compatibility checks) Specification (we can provide R10 type spec.)

HydroMax™ Siphonic Drainage Leaders in Siphonic Drainage www.hydromax.com