NATURAL VENTILATION COMMERCIAL BUILDINGS INNOVATIVE VENTILATION & HEATING

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1 NATURAL VENTILATION COMMERCIAL BUILDINGS A guide to Natural Ventilation, including our unique solution offerings, consultancy service and recommendations. INNOVATIVE VENTILATION & HEATING

2 Natural ventilation is a proven, low energy, environmentally friendly solution that controls airflow to create a comfortable and productive building. We supply a number of natural ventilation strategies with a commitment to offer a positive and effective solution. As well as less space required for plant rooms the benefits are many. Economic benefits: Low maintenance; Low capital cost; Low running costs. Environmental benefits: Low energy use; Greenhouse gas reduction; CO 2 reduction. User benefits: A control system to create comfortable conditions. At Price TWA we believe in providing a quality service with quality products, our approach is professional and knowledgeable and we hope to show this in everything we do we constantly strive to be the best. OUR SERVICE It is important to consider natural ventilation in early development, as efficiency and aesthetics can be greatly improved when integrated into a building s design. Our dedicated team of engineers and technical specialists will be available to offer a comprehensive range of services from application analysis, product advice and design, through to scheduling supply and installation.

3 DELIVERING INDUSTRY EXPERTISE Price TWA was formed in 2008 from the merger of two leading heating and ventilation suppliers in the UK, Price Technical Ltd (Formed in 1997 to supply high quality ventilation and heating systems) and TWA Panels UK Ltd (formed in 2003 to supply radiant heating panels). Together we now offer one of the widest ranges of heating and ventilation solutions in the UK. We are recognised in the industry not only for excellent design and manufacture of heating and ventilation systems but also for maintaining strong relationships with both suppliers and contractors. This combined with our strong manufacturing background has set us among the very best of the UK s heating and ventilation solutions providers. OUR EXPERIENCE We have grown and adapted as the construction industry has, offering modern solutions to modern issues. We understand that every project has individual needs and always offer flexible informed solutions to meet the needs of every project. Years of experience and industry expertise will provide you with a solution that s cost effective, efficient and suited to your building s individual design and function. Within this brochure we detail and compare each of our natural ventilation strategies including details on component parts. We operate from our manufacturing base in Bristol where we create and distribute our products. We have a dedicated team of sales engineers and representatives throughout the UK and Ireland offering exceptional customer service. VENTILATION STRATEGIES PRINCIPLE STRATEGIES P4 WIND DRIVEN CONTROLS P7 HYBRID PASSIVE STACK ATRIUM P8 NIGHT COOLING STRATEGIES P4 SINGLE SIDED CROSS-FLOW PASSIVE STACK P7 CONTROLS P8 PASSIVE STACK & ATRIUM P9 WIND DRIVEN P10 HYBRID P11 NIGHT COOLING COMPONENT PARTS P12 PENTHOUSE LOUVRES & THROUGH WALL VENT P9 P10 P11 PRIORITY SCHOOLS P14 BUILDING PROGRAMME COMMITTED TO BECOME THE INDUSTRY S LEADING SUPPLIER OF VENTILATION AND HEATING IN THE UK +44 (0) NATURAL VENTILATION 3

4 PRINCIPLE NATURAL VENTILATION STRATEGIES SINGLE SIDED Wmax ~ 2.5 H CROSS-FLOW Wmax ~ 5 H PASSIVE STACK Wmax ~ 5 H H H H W W W Single-sided ventilation allows air-flow into a building with an inlet and outlet on a single façade. This solution offers simple air distribution. Guidance only. Dynamic modelling in conjunction with building design may result in different ratios. With an inlet and outlet on opposite walls, cross-flow ventilation allows airflow to be naturally driven through a space using differences in façade pressures. Passive stack combines air buoyancy with a roof mounted turret that creates a suction effect. Airflow naturally passes through the building and is drawn out of the turret using internal heat gains and pressure differences. NATURAL VENTILATION OFFERS LOW MAINTENANCE, LOW ENERGY, NO NOISE & REDUCED CO 2 EMISSIONS Concentration of C0 2 (ppm) :00 CO 2 levels during a school day 3 l/s/p 5 l/s/p 8 l/s/p 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 Maximum average INDOOR AIR QUALITY Regulations and guidelines dictate industry ventilation standards and natural ventilation is no exception. Building Bulletin 101 states that the maximum average concentration of CO 2 levels must be below 1500 ppm. Required levels: Minimum 3 l/s/p Daily average 5 l/s/p Design capability 8 l/s/p Time (0) NATURAL VENTILATION

5 APPLYING NATURAL VENTILATION A natural ventilation solution requires many design integrated considerations, some of which are essential to creating an effective result. Understanding the purpose of a building, where it is situated and how it is going to be built allow us to consider the most effective way to integrate natural ventilation. The three main factors that need consideration when creating a successful natural ventilation solution: PERFORMANCE GUIDELINES All our strategies are designed to meet current standards, which include air quality, energy consumption and CO 2 levels, internal temperatures and noise considerations. Our solutions are designed to meet the standards outlined in the following documents: Approved Document F Approved Document L2 Building Bulletin 101 & 93 CIBSE AM10 Priority Schools Building Programme NATURAL VENTILATION OFFERS LOW MAINTENANCE, LOW ENERGY, NO NOISE & REDUCED CO 2 EMISSIONS OCCUPANCY Numbers and activity Building purpose CO 2 emissions Heat gains Equipment ENVIRONMENT Location Orientation Noise levels Wind direction Temperature BUILDING DESIGN Building materials (Heavy/Light thermal mass) Architectural features Size of windows and apertures Dimensions (width vs. height) +44 (0) NATURAL VENTILATION 5

6 CONTROL SYSTEM Controls are an essential part of an efficient Natural Ventilation solution. They allow the airflow into each room in a building to be adjusted using high and low level dampers, which can be controlled according to internal and external temperature, CO 2 levels or humidity. Controls are increasingly covered by a central BMS system, but can also be covered by a standalone control system, typically by a control specialist. CONTROL FUNCTIONS TEMPERATURE (INT & EXT) TEMPERATURE KNOWLEDGE CO 2 SENSOR BMS Maintaining good indoor air quality is an important consideration and is generally monitored using CO 2 sensors. Maintaining adequate CO 2 levels is also a requirement of the Education Funding Agency s Facilities Output Specification and BB101 for ventilation in schools. AIR QUALITY (CO 2 ) CONTROL TIME KNOWLEDGE APERTURE OPENINGS NIGHT COOLING CO 2 levels can be indicated in a room, typically using traffic light system of light which can either indicate to the user to respond, or to give a visual indication of air quality and how the ventilation is operating in response to such levels. CONTROL PHILOSOPHY We most commonly advise on control requirements, either at design stage or later in the project development, many projects are covered by a central Building Energy Management System (BEMS) supplied under specialist contract. It is important that this aspect of the system is well coordinated and is an area we can readily assist with, whether with the design, project team or control specialist. WEATHER STATION An external weather station allows the control system to respond to conditions automatically. The sensors typically monitor some or all of the following: Outside air temperature Wind speed Wind direction Rain CONTROL MODES AUTOMATIC MODE WINTER MODE MANUAL OVERRIDE This is typically set to provide good ventilation throughout the year operating within set temperature and CO 2 parameters. BMS integration gives the option of a fully automated ventilation system. Winter mode is a common function automatically triggered to restrict airflow when external temperatures are lower than, say, 14 C. Designed to avoid the loss of warm air It is also important to consider set points for heating systems and heating system design to ensure ventilation can be delivered whilst maintaining the desired internal temperature. Manual override is an important consideration to give users control in a space and should typically allow fully open, closed and auto commands. The function is typically set to operate for a set time period before reverting back to automatic operation (0) NATURAL VENTILATION

7 PASSIVE STACK/ATRIUM NATURAL VENTILATION PASSIVE STACK/ATRIUM STRATEGY Often the most effective strategy as it combines cross-flow, air pressure differences and rising warm air to increase airflow. Passive stack encourages warm air to rise through rooms and exit through a vertical air-path, such as an atrium. Wmax ~ 5 H THROUGH WALL VENTS EXHAUST THROUGH ROOF BUILDING DESIGN Buildings that use Passive stack or Atrium natural ventilation strategies require many design considerations to create an effective result. The size and positioning of windows and apertures should vary depending on distance from the exhaust. Greater thermal mass of a building will aid night cooling. Architectural features such as tall atrium s, turrets and sloping roofs will aid air movement making the solution more effective. THROUGH WALL VENTS OUR THROUGH WALL VENTILATION IS DESIGNED FOR MODULAR ASSEMBLIES THROUGH WALL VENTILATION EXTERNAL/INTERNAL LOUVRES Our louvres are available in a wide range of options including size, blade configuration and frame type. Finish options include powder coating to any classic RAL colour specification. Single or triple bank systems Extruded aluminium Blade configuration Weather protection High air flow Class A weather effectiveness to EN13030 when assembled as a through wall vent OPTIONAL EXTRAS Acoustic baffles single, double and triple bank to reduce noise levels (internally or externally) Heater batteries incorporated into inlet to temper incoming air MOTORISED DAMPERS Our dampers are available in a number of options to suit different design needs, including models with insulated casing and with either manual adjustment or actuator operation. Thermally insulated with low U value Tight shut-off for low leakage performance Interlocking blades with double blade seals Slim construction Can be combined with other components OPTIONAL EXTRAS Includes a variety of actuator options such as modulator open/ close 24V and 230V +44 (0) NATURAL VENTILATION 7

8 WIND DRIVEN NATURAL VENTILATION WIND DRIVEN STRATEGY Dependant on wind behaviour, wind driven ventilation harnesses prevailing wind to supply fresh air into an indoor space using a rooftop turret. This air then displaces and exhausts the warmer, stale air out of the same turret. ENVIRONMENT Wind Driven natural ventilation must take into consideration the location and orientation of a building. Ideally the roof should be higher than surrounding buildings to allow the wind to be captured, and the direction of the prevailing wind can help determine the best positioning of the turrets. AIRFLOW INLET EXHAUST WIND DIRECTION FRESH AIR STALE INDOOR AIR AIRFLOW INLET EXHAUST TURRET AIR FLOW Wind-flow is captured with the opening side(s) of the turret facing the wind direction. This air is then driven down into the room below where it circulates and mixes with the stale indoor air. Warm air rises out of the space and out of the remaining quadrants. ISOLATED ROOM A DIVIDED DUCT ASSEMBLY ALLOWS FOR INLETS AND OUTLETS IN ONE UNIT CASE STUDY NANT CELYN PRIMARY SCHOOL Nant Celyn primary school includes the regional centre for the Hearing Impaired. As well as meeting Building bulletin 101 standards, attention was required to control acoustic performance in classrooms. The build included: Eight wind driven turrets Weatherproofing BMS control integration Acoustic insulated splitters THE BENEFITS ACOUSTIC PERFORMANCE REDUCED ENERGY USE IMPROVED CARBON FOOTPRINT IMPROVED LEARNING ENVIRONMENT COST EFFECTIVE SOLUTION (0) NATURAL VENTILATION

9 HYBRID NATURAL VENTILATION HYBRID STRATEGY Hybrid ventilation uses a boost fan system to assist natural ventilation. This strategy will come into use particularly during summer months and winter months to maintain comfortable conditions. PENTHOUSE LOUVRES TURRET (BOOST MODE) The hybrid strategy offers extra support to the wind driven natural ventilation configuration. If wind pressure and temperature differences are not sufficient to drive airflow, a boost fan is fitted into to ducting to generate air movement usually for peak occupancy, but also to mix cool air in winter months when wind turbulence may not be enough, or cold draughts need to be avoided. HIGH INDUCTION SLOT DIFFUSER THE ADVANTAGES Can offer rapid cooling with higher levels of air movement Can quickly improve air quality Mixes cool air with warmer room air, reducing cold draughts Uses a highly efficient EC fan and high induction slot diffuser OUR HYBRID SYSTEM OFFERS CONTROLLED BOOST FAN VENTILATION SUPPORT CASE STUDY SOUTH DEVON UTC South Devon University Technical College was designed to accommodate up to 600 students as the first UTC in the area. A Hybrid natural ventilation strategy was used that supports a wind driven solution in their sports hall. The build included: Wind driven hybrid vent turrets Weatherproofing BMS control integration THE BENEFITS REDUCED ENERGY USE IMPROVED CARBON FOOTPRINT IMPROVED SPORTS HALL ENVIRONMENT COST EFFECTIVE SOLUTION +44 (0) NATURAL VENTILATION 9

10 NIGHT COOLING NATURAL VENTILATION NIGHT COOLING STRATEGY The thermal mass of building materials play an important part in the effectiveness of this strategy. Building materials with high thermal mass will retain cool temperatures when exposed to night cooling. UNOCCUPIED AT NIGHT SEALED/CLOSED IN THE MORNING INLETS OPEN INLETS CLOSED THERMAL MASS THERMAL MASS By increasing airflow and flushing out warm air, night cooling can significantly reduce a building s core temperature and in turn keep a building cooler for longer in mornings. The building is sealed in the morning keeping warmer air out. The building will remain cool for a period of time depending on thermal mass and occupancy. A BUILDING S THERMAL MASS CAN HELP REDUCE PEAK DAYTIME TEMPERATURES CASE STUDY PAIGNTON LIBRARY The central library was designed to include night cooling and to meet the environmental assessment BREEAM rating Very Good. With adjacent roads and train station this provided a challenging environment that required integrated acoustic baffles to control noise levels. The tall stacks were provide greater air movement as well as a striking design feature. The build included: Passive stack turrets Weatherproofing BMS control Design integrated through wall ventilation THE BENEFITS ACOUSTIC PERFORMANCE REDUCED ENERGY USE IMPROVED CARBON FOOTPRINT COST EFFECTIVE SOLUTION (0) NATURAL VENTILATION

11 PENTHOUSE LOUVRES TURRET STANDARD DETAIL ALUMINIUM CROSS FOLDED ROOF MULLION FRAME INCLUDES WEATHER ELIMINATOR BAFFLE (NOT SHOWN) LOUVRE BLADES BLADE CLIPS ALUMINIUM CILL GALVANISED DUCT SLEEVE GEARS DAMPER BLADES OUR PENTHOUSE LOUVRES HAVE BEEN SPECIFICALLY DESIGNED TO OFFER MAXIMUM AIRFLOW AND SECURE WEATHERPROOFING EGG CRATE GRILLE FEATURES Tight shut-off for low leakage performance Interlocking blades with double blade seals High air flow Can be combined with acoustic baffles Heater batteries can be incorporated Class A weather effective to EN PENTHOUSE LOUVRES Our penthouse louvres are created on our manufacturing base and assembled ready for on site delivery. Each unit can be customised to meet individual size, design and colour requirements. +44 (0) NATURAL VENTILATION 11

12 THROUGH WALL VENT STANDARD DETAIL INTEGRAL BIRD MESH C/W OPTIONAL INSECT MESH LOUVRES (INTERNAL) DAMPER BLADES (THERMALLY INSULATES TIGHT SHUT OFF) GEARS ACTUATOR FLANGE FRAME EXTERNAL LOUVRES ( GLAZED IN AND RECESSED FRAMES AVAILABLE) OUR SLIM CONSTRUCTION THROUGH WALL VENTS OFFER A THERMALLY INSULATED, WEATHERPROOF VENTILATION SYSTEM FEATURES Tight shut-off for low leakage performance Interlocking blades with double blade seals High air flow Can be combined with acoustic baffles Heater batteries can be incorporated Class A weather effective to EN up to 2.5 m/s as an assembly THROUGH WALL VENT Our louvres are available in a wide range of options including size, blade configuration and frame type. Finish options include powder coating to any classic RAL colour specification (0) NATURAL VENTILATION

13 NOTES +44 (0) NATURAL VENTILATION 13

14 PRIORITY SCHOOLS BUILDING PROGRAMME The Education Funding Agency s Priority School Building Programme forms a major area for the application of natural ventilation systems and includes additional requirements for thermal comfort along with proposals for both natural and mechanical ventilation. Part of the programme was to produce a number of Baseline Designs which could be used as a basis for developing a detailed design for a school. Some of the general arrangements are shown here for reference. DELIVERING EXPERIENCE As an experienced supplier of natural ventilation, we are well placed to deliver solutions to schools projects having worked on many school projects, just two of which are shown as case studies in this brochure. Our through wall vents with acoustic baffles are particularly well suited to sites where external noise is a factor; our roof level penthouse exhaust units offer proven weather effectiveness and; hybrid vent units can offer mixing of external air within the room it is serving to avoid cold draughts. B B Education Funding Agency EFA Baseline School Designs Secondary Type Section BB Typical Curriculum Scale: N/A Dwg. No.: D LONG SECTION (0) NATURAL VENTILATION

15 B B Education Funding Agency EFA Baseline School Designs Secondary Type Section BB Typical Curriculum Scale: N/A Dwg. No.: (0) NATURAL VENTILATION 15

16 Tel: +44 (0) Web: INNOVATIVE VENTILATION & HEATING Natural Ventilation Radiant Panels External Louvres Chilled Beams Heat Recovery VAV/CAV Boxes Displacement Grilles & Diffusers Air Handling Units Fan Coil Units Price TWA is a trading name of Price Technical Limited. Registered Office: Unit 1, Smiths Forge Ind Est, North End Rd,Yatton, Bristol BS49 4AU. Registered in England No Price TWA Version.2