Make your expertise uniquely valuable. Duct Smoke/Fire DampersCombined smoke and fire damperssuitable for use in all types of HVAC ductwork. 1 KB Views: 234. DG-3 - Double Flange Door/Transfer Grille. When posting in certain forums, knowing your location will. We are ready to support all customer inquiries: Customer service: [email protected]. The Waterloo fire rated ventilators are suitable for 1 hour rated doors and partitions. Day-to-day this enables efficient ventilation but during a fire will seal shut, stopping the fire spreading further. 4. Door, Wall or Partition Mounting. fitting a conventional grille to a wall or door will totally negate other measures taken to prevent the spread of fire, hot smoke andGRILLES 2 JUNE 2018 PUBLICATION Features - Single or Double Deflection. Typical Building Sector : Commercial,Dom. James Gilbert grilles can be made in all of the above metals. This is partly due to a privacy issue. Transfer Grilles offer the largest free area possible with the option of a sight-proof or light-proof core. BBB Accredited Door and Gate Operating Devices near Victoria, BC. Door/Transfer Grilles. testregistrierung. Take a flow hood and check cfm with the door open and the door closed, with a 1" undercut on a bedroom door you will have a serious cfm drop. Est. com 0344 856 0590. 600 Series 5600 - Aluminum Transfer Grille with Single Flat Frame 5600A - Aluminum Transfer Grille with Single Flat Frame (Auxiliary Frame) 600 - Steel Transfer Grille with Single Flat Frame 600A - Steel Transfer Grille with Single Flat Frame (Auxiliary Frame) 600C - Steel Transfer Grille with Channel Frame. GILBERTS Head Office and Works GILBERTS (BLACKPOOL) LTD Gilair Works, Clifton Road, Blackpool. Designed for door mounting. Horizontal and vertical moving slats for an individual regulation as they adapt the air range and the air stream to the needs of the zone. 1 800 222 5932. Also, there is NO indication of the how to determine the required size of the permanent openings of any type. Brass is one of the most popular materials for decorative grilles but most often brass grilles are used internally where the finish on the woven lattice or decorative screen will be more stable. That does not even come close to the negative pressure issues it throws the rest of the home into. Formed in 1987, DBA Air Solutions have provided advice, support and a wide ranging source of knowledge within the HVAC industry for over 30 years. Established in 1972 in the family garage, HVC Supplies has developed steadily over more than 45 years to become the industry leading company it is today. Transfer ducts may achieve this by increasing the return transfer 1 1 / 2 times the cross sectional area (square inches) of the supply duct entering the room or space it is serving and the door having at least an unrestricted 1-inch undercut to achieve proper return air balance. Narrow 40mm and 44mm Thickness. Sort by. 005 150. Download the pdf to learn. We are committed to clarity in pricing which is unambiguous although this Site does not contain any pricing information. Length : 80 mm. Catalog. Discreet, but attractive, this robust extruded aluminium grille incorporates a slotted, linear airway across its length and locates at the bottom of the door single doors, double doors and louvre screens. The Perfect Balance In-Door Return Air Pathway is a Durable ABS plastic grille with a noise and light dampening baffle that is installed into the bottom of interior doors. uk. Registered in England and Wales: 673483. The above-door transfer grille simply has two grilles located above the door between the room and common space, one on each wall, with offset baffles to limit sound transmission. with a door sleeve and electrical door wiring loop for a 45mm or 54mm door or a wall sleeve only, for a wall/partition. Over the last 135 years we've produced architectural quality metal works for some of the biggest brands on the planet, yet we don't forget our. H Nominal grille heigh t. Volume Control DampersStandard and large format air volume control dampers for ducted air systems. Career. The LVH intumescent air transfer grilles available from Lorient Pty Ltd are specifically designed for use in fire rated door assemblies where pressure relief or extra ventilation is required. View Product. The 61DG Series Door Grille may also be used as a transfer grille and in place of standard design exhaust and return air grilles where it is important that the interior of the plenum or duct be concealed. Table 1RCM PRODUCTS, 12-14 Sunbeam Road, Kempston, Bedford, MK42 7BY T: 01234 843303 F: 01908 483930 E: [email protected]Transfer grilles are designed for use in doors and partitions to allow for smooth transfer of air between spaces. It adjusts to suit a door thickness from 1-3/8" to 1-7/8". Du ctodamp esl v ni 7. Installation is simple and should only take 30-45 minutes with the right tools. Model Series 51DG offers the largest free area possible (average > 50%) with a completely sight-proof. 6 104 ratings. To contact us please call: +44 1253 766911. NV3 is a Vision proof core in 32mm flanged border with matching telescopic back flange. These are specially designed which also giving a pleasing appearance to suit architectural needs. Download. From standard grilles and registers, to its architectural line of Formations® linear slot diffusers, along with a newly released series of displacement. Intumescent air transfer grilles to satisfy air transfer application in doors or walls. GRILLES 9 OCTOBER 2021 PUBLICATION Features - Door or Wall Mounted. These airflow volumes are then used to size and lay out the ducts. ft. 9% and improve hygiene. Manufactured using modern<br />. 3. 1"x3. Go to. All manufactured from 1. 005 150. 10 Wigford Road Masons Mill Pietermaritzburg Tel. 020 inch water column) is acceptable for rooms with a design airflow ≥150 cfm. London’s Decorative Metalwork and Metal Grille Specialist. Width : 1025 mm. Duct diffusers. Air transfer grilles. NV3: Double layered grille intended for dark rooms (supplied as two modified NV1 grilles). 006 0. Gilberts Non-Vision Louvred Grille | Air Transfer Grille Cover. SCHAKO sight-proof transfer grilles are overflow grilles for walls and doors and are used between two adjacent rooms for pressure compensation. PAGE 132 Door/Transfer Grilles GREENHECK offers a complete line of door and transfer grilles with a variety of options for sight proof or lightproof applications. The DG door transfer grilles are designed for use in doors where constant air transfer with non-vision is required. Table 1 shows the sizing specifications for using 10”, 12” or 14" wide transfer grilles with 70% free area as a function of room supply air flow. Series SK Heavy Duty. AG60 Bar Grille. Titus Door transfer grilles are great for use indoors and partitions. 008 0. 2. 2. Fabricated in a plain industrial grade 304 and 430 stainless steel the units are very robust and are suitable principally for Acoustic, smoke + fire containment systems. Such spaces include storage rooms and restrooms. Therefore: Total No of Grilles = 10m3/s = 57. The Perfect Balance and Return Air Pathways. 53. NV1 Grille. Used to allow for air movement between two conditioned spaces while preventing vision. The damper units are slimline with an overall thickness of only 35mm, allowing these kits to be flush fitted within the conventional 35mm & 45mm nominal fire door leaves. AG50 Bar Grille. Allows for air transfer through doors or walls. ) while at the same time offering effective protection against flames, smoke and gases in case of fire. The standard finish will be RAL9010 or polyester powder coated to. In many cases, pipes and ducts. Door / Transfer Grille Extruded Aluminum 10/19/2022 Inches 1 1 DGSF Single Flange Frame 1. 2. Note: When framing both sides of the door or partition opening, use the TGF frame with the TG Grille. Get Quote. Steel Maximum Security Transfer Grille with Rounded Perforations. Non-vision air transfer grilles, made of aluminium, withRETURN GRILLE DOOR/TRANSFER GRILLES MODELS: DG-I, DG-2, DG-3 DG-I CORE ONLY 11/16" 5/16" DG-2 Single Flange SUSTATNABLE EXTRUDED ALUMINUM Dimensions are in inches (mm) a DG-I Core only Door Transfer Glille a DG-2 Single Flange Door Transfer Glille a DG-3 Double Flange Door Transfer Glille OPTIONS: 11/16". The Perfect Balance is typically installed in a bathroom or mechanical room door for the purpose of providing make up air for the exhaust fan. The LVN20 is a non-vision intumescent air transfer grille. * Note: 30mm protrusion with minimum depth of door DSR/425/285/9010-Matt Type Nominal width Nominal height Finish ORDER EXAMPLE Nominal W x H + 51 Nominal W x H - 25 60 Nominal W x H 40. Transfer grilles shall use 50 square inches (. Air transfer grilles are vents that are fitted into doors or walls to allow air to move freely around a building, helping it to stay ventilated. VAT Number: GB 154 1026 07. Carpets will filter the air and remove all the candle soot and other airborne particulate, as it is forced under the bedroom door due to a high pressure difference. V-shaped Deflection Vanes Set on 1/2” Centers. Envirograf Firoblok | Intumescent Sleeve for Services - Silver, 360 X 204 X 60mm. Such spaces include storage rooms and restrooms. GRILLES AND REGISTERS F DOOR/TRANSFER GRILLES PERFORMANCE DATA: DOOR/TRANSFER GRILLES – 5100 AND 6100 SERIES MODELS: 51DG, 61DG Listed Duct Size (inches) Alternate Sizes (inches) Core Area (sq. Air transfer grille FGS - type MMS represent passive fire protection, designed with the help of compartmentalization to prevent the spread of toxic gases, smoke and fire. 012. The Perfect Balance is a transfer grill designed to fit in the door. It's annoying that you can hear everything that goes on in the house due to the transfer grilles above the door. Aluminum Transfer Grille (ATG) Overview. This gives good room ventilation as a result of mixed ventilation. fitting a conventional grille to a wall or door will totally negate other measures taken to prevent the spread of fire, hot smoke andGrilles Type AH · WAP · AF Installation situation Type AH, AF ≥X Nomenclature ‡ in l/s/m based on 1000mm nominal grille length . DESCRIPTION: Construction: Frame and blades are 6063 extruded aluminum alloy with 200-R1 satin anodized finish. • Height in 85 mm steps (blade pitch) • Door thickness: from 37. We can accommodate bespoke sizes or larger quantities – please get in touch with our team on 02920 857. The negative pressure on that duct of your HVAC system will mess with the air distribution in weird (bad) ways, and it's almost certainly not big enough for what the dryer will be trying to pull. NV2 is a Vision proof core in 32mm flanged border. Door Transfer Grilles. We take great pride in offering an exceptionally high level of customer service and in building long-term relationships with our clients, whether they be consultants. Genuine Comfort find that air return grilles tend to be the better choice between transfer grilles and air return grilles. Return Air Pathway In-door vent, In-wall vent, and also specified in as a Transfer Grille. Used to allow for air movement between two conditioned spaces while preventing vision. Blades are chevron in configreation and are mounted in a fixed position ina rigid PVC track in an integral part of the frame. Gilberts’ NV3 door transfer grilles allow Regulatory flow of fresh air whilst being vision proof. wait: 1 min. SG-PS. Clearance dimension 430x75 mm. Construction is from all aluminium extrusion with fixed full chevron blades. Available lengths: 72, 97, 147, 197, 222, 247, 297, 347, 397, 447, 497, 547, 597, and 1000mm. A typical bedroom door would be 28”-30” wide, very good chance there’s a little stud somewhat in the middle to hold up the drywall (they’re usually at every 16”). 1. 200. Engera Bathroom Door Air Vent Grille Two Sided Ventilation Cover for Restroom, Warehouse, Storage Doors | Interior Door Transfer Grill 453mm x 91mm (18. Aluminum Construction. 4. Series GP Security Grilles. where air transfer is desirable but fire requirements must be met. Any guidance the committee could provide in this area would be most helpful. Series FB Air Transfer Grille. ) Ak Factor Core Velocity Velocity Pressure Neg. 02576. Coat Hook Remove all hooks behind doors, in wardrobes, etc. Construction is from all aluminium extrusion with fixed full chevron blades. 001. Air Distribution | GDL Air Systems Limited | England ATG. This air transfer grille cover is suitable for both standard air transfer and fire rated applications. In line with the smaller Louvres this series offers a high resistance to weather ingress combined with a good 50% free and both flanged and recessed channel frame options can be selected along with standard bird guard and insect screen accessories. NV2 Grille. Door/Transfer Grilles. 001. ls in m = Throw distance to a bmaximum time averaged air vel ocity of 0. Door Transfer Grilles. 3. 7 m2) of under-floor area, including a return air pathway to the common area (such as a duct or transferAcoustic, smoke + fire containment systems. TAMARACK R. Minimum size is 6" x 4" (152 x 102). For installation information not covered in this sheet, refer-ence appropriate damper basic installation instructions. Original plan was to take my central air return in the hallway and stub ducts in the attic to get individual air returns to each bedroom. : Bedrooms with a design supply airflow ≥ 150 CFM are specified with any combination of transfer grilles, jump ducts, dedicated return ducts, and/or undercut doors to achieve a Rater-measured pressure differential ≥ - 5 Pa and ≤ +5 Pa with respect to the main body of the dwelling unit when all air handlers are operating. Apply a bead of Pyroplex Intumescent Acrylic Sealant centrally and spread the acrylic across the full width of timber liner, to achieve a thickness of 0. Intumescent air transfer grilles to satisfy air transfer application in doors. Really Helps with transfer air and the rooms feel more comfortable when the door is closed since the air pressure is not building up without a way to return to the air handler. Standard finish is natural anodised while other finishes including powder coat are available to suit the interior and architectural design requirements. Available in either steel or aluminum construction with either single or double flange frame options. Air Velocity : 75 m/s. High – low transfer grilles. 57 (29 grilles required) 0. 1 800 222 5932. Gilberts NV Series provides a comprehensive and traditional range of vision proof grilles to suit all manner and type of air transfer application through doors, walls and partitions. A jump duct is a short piece of insulated flex duct. Designed for installation into fire resisting doors, walls and ducts. Your guide to trusted BBB Ratings, customer reviews and BBB Accredited businesses. Such spaces include storage rooms and restrooms. Series XG-DG extruded aluminum door grilles are designed to transfer air through doors or walls. Standard and bespoke aluminium louvres offering excellent functionality and rain defence. 004 0. Alternatively, please contact TENMAT for details of suppliers of finished grilles complete with steel frame and steel faceplate louvres. DSR units may be used in series to increase transmission loss. X. Downloads. Transfer units. . Custom designed to meet all architectural and HVAC industry standards, our linear bar grilles will provide you with optimum durability and performance in any environment without sacrificing aesthetic appeal. The above-door transfer grille simply has two grilles located above the door between the room and common space, one on each wall, with offset baffles to limit sound transmission. 01457 861 538. The Waterloo fire rated ventilators are suitable for 1 hour rated doors and partitions. Attenuators, Acoustic Louvres/Enclosures, Acoustic Transfer Grilles, Acoustic Fire Doors, Anti-Vibration Springs and Hangers. TRH-A series grilles have a simple design which makes them useful for incorporation in all styles of architecture. 450x92. My 1st choice would be jumper ducts for aesthetics and better air volume capabilities. Envirograf Firoblok | Intumescent Sleeve for Services - Silver, 360 X 204 X 60mm. transfer of room air to another, i. Transfer grilles are designed for use in doors and partitions to allow for smooth transfer of air between spaces. AGS. w. It's a return grille, most likely. Easy to assemble. 40 + VAT. They can be used for providing dampers in ductwork. Door grilles are required for the transfer of air from one room to another Material Door grille manufactured from. 00 - $80. Standard finish is natural anodised while other finishes including powder coat are available to suit the interior and architectural design requirements. Still family owned Gilberts operates from its 120,000 sq ft manufacturing base in Blackpool, Lancashire with an annual turnover in excess of £20 million. There is an HVAC register in the ceiling, so maybe it can pull the fresh air in through the ductwork? Or should I add a transfer grille in the drywall above the door to let air pass more freely?The air transfer grilles are connected, via a control panel, to a standard fire alarm system. Also associated with high pressure. If it’s a load bearing wall with a big header above the door jamb leave it as is, if it’s just to hold the drywall you can reframe accordingly. Static Pressure 100. It may be surprising that just these three systems — mechanical, electrical and plumbing (MEP) — can make up as much as 15% of the total environmental footprint of a building's materials. 002. 25. Uniclass Code : Pr_70_65_04_03. 5m/s and NC level less than 15. Gilberts NV Series provides a comprehensive and traditional range of vision proof grilles to suit all manner and type of air transfer application through doors, walls. Still family owned Gilberts operates from its 120,000 sq ft manufacturing base in Blackpool, Lancashire with an annual turnover in excess of £20 million. 0006 0. I just finished building a new home and as part of the Energy Star rating transfer grilles were installed above each of the bedroom doors to allow air exchange when the doors are closed. Yes, you should absolutely install a dedicated grille. . 6 inches : If the free area of grille is %, and side (a) is" , side (b) should be: 3. Published by Raúl Galdrán from BIMETRICAL on 1/8/2018. DG-3 - Double Flange Door/Transfer Grille DESCRIPTION: Construction: Frame and blades are 6063 extruded aluminum alloy with 200-R1 satin anodized finish. For more friendly and professional advice on air grilles, please get in touch via our contact us page or give us a call on 01842 765657. Pyrogrille air transfer grille allows free air flow and provides up to 60 minutes fire protection. air transfer grilles to satisfy air transfer application in doorsor walls. Wrapping up smoke and fire protection with our range of Fire Dampers, Smoke Dampers, Smoke/ Fire Dampers, Intumescent Air Transfer Grilles and Air Volume Control Dampers all developed to the latest test standards. This may cause the damper to scream. Send us a messageDG-3 - Double Flange Door/Transfer Grille. TRH-A series grilles have a simple design which makes them useful for incorporation in all styles of architecture. Operation: The units are operated by a 24V DC electrical supply. Download. SERIES OPTIONS WGF/75:Comprises of 16 SWG LouvresThe grille is also suitable as a general replacement for 600sq floor tiles where areas of heavy foot traffic and equipment would be experienced. Supply and extract grilles for all building types including double and single deflection grilles, egg crate cores, security grilles and data centre floor grilles. 6145H - Steel • 45° Deflection. Clearance dimension 430x75 mm. Login / Register; 0117 9372846;. The DV series are large format grilles for door ventilator applications. Available Accessories 3. Our range of Non-Vision Grilles models include: NV1: Standard flanged grille. 3 Slimline Floor Grille ASGF 15 1. The LN linear bar grilles have bars fitted flush with the flange face, angled at Capital Building to 15degrees to ensure airflow without draughts. Manufacturer : Madel. As Featured On. And with an experienced team of Sales. T. AG20 Bar Grille. View an intumescent ATG fire test here. Duct Smoke/Fire DampersCombined smoke and fire damperssuitable for use in all types of HVAC ductwork. 452 likes. Air Velocity : 75 m/s. Door Transfer Grille Ordering Specification Sizing Finish Introduction Gilberts AV1601 Series presents an attractive alternative to traditional vision proof door mounting air transfer grilles. . Over the last 135 years we've produced architectural quality metal works for some of the biggest brands on the planet, yet we don't forget our. Width : 1025 mm. 012. Actuator (location varies) 8. jpg. 3. A high performance, standard vision intumescent air transfer grille for walls, doors and ventilation ducts. HVAC OV 17. Download. GRILLES AND REGISTERS F DOOR/TRANSFER GRILLES PERFORMANCE DATA: DOOR/TRANSFER GRILLES – 5100 AND 6100 SERIES MODELS: 51DG, 61DG Listed Duct Size (inches) Alternate Sizes (inches) Core Area (sq. 6" Inch Door Air Vent Grille Two Sided Ventilation Cover - White - Overflow Ventilation Grill - Door Vent Cover - Free AIR Flow Between Rooms -. Allowing air movement through a door or wall without compromising fire integrity. Construction Details All Dimensions ±1/16" Standard Finish: 01 White Finish 24 Mill Finish Optional Finish 02 Satin Silver 03 Black 28 Custom Color Extruded Aluminum Constructionjinteriordesignonline. TransShield ACS is a slimline non-vision intumescent fire and smoke damper with a unique sliding plate smoke control system. Long throw, high capacity supply grille with rotating drum. Model DG-FC Louvre Grilles are available in stock sizes and can. DL. Grille face made of aluminium with anodised finish. GILBERTS DAMPERS 8 MAY 2005 PUBLICATION Features 60 or 120 Minute Fire Rating. Both the Halton TVC grille and opposite frame are screwed to the wall or door. London’s Decorative Metalwork and Metal Grille Specialist. supplied by Gilberts with each Grille batch. HVC Supplies offer one of the widest ranges of grilles, diffusers, louvre systems, volume control dampers and fire dampers available from any UK manufacturer, with our range being constantly expanded to suit new industry requirements and customer demands. 61EC - Steel Frame, Eggcrate. The air transfer grilles are connected, via a control panel, to a standard fire alarm system. The Halton TVC transfer grille can also be used together with an opposite frame accessory (OF) to complete transfer unit for 25 to 50 mm thick doors or partition walls. application. The only place I can install transfer grilles is above the doors. Acoustic, smoke + fire containment systems. ×. 05 m 3 /s) (of supply air ) for sizing through-the-wall transfer grilles and using an unrestricted 1-inch (25 mm) undercutting of doors to achieve proper return air balance. In the event of an alarm condition, or power failure, the smoke shutters shut, preventing the passage of cold smoke. The DGA4 vents in the toilets feature a louvred face for a horizontal air pattern. Curtain Rails Collapsible rails and safety track Curtain Tracking Avoid gaps in fixed tracking Curtain Wires Avoid use of curtain wiresThe Advanced Air Model Series 51DG Door Transfer/Non-Vision Grilles are designed to meet the demand for top quality andcompetitive prices. 18 Registers, grilles and diffusers. Supply you have the fan to move air the returns are all low air pressure and do not work as well. Height : 1005 mm. 4 Dimensional Data Hole - 4mm dia. - Quality 0. ) Nominal Size Core Velocity (fpm) 100 150 200 250 300 350 400 Velocity Pressure (in. XG-DG Series. 7mm Mild Steel Construction. To provide a pathway for air from rooms with closed doors to these central return registers, builders can use door undercuts or install transfer grilles or jump ducts. Trimec. by. On the roof, 3 number penthouses, ranging from 1m x 1. A door or partition non-vision grille incorporating inverted chevron blade…. 55 KB: Preview: waterloo-air-products-plc_ns-non-vision-transfer-grilles_photo_3_d32b8ba8-bdc8. (Matt black finish). - Attractive Slimline Appearance. A. 3 (7) Download. This is partly due to a privacy issue. “While undercutting doors can create part of the return air path, wall transfer grilles or jump ducts should be installed to prevent the return problems,” the Building Science Corporation warns. Gilbert's Delicatessen, Guelph, Ontario. The DGC door transfer cavity grille are the most economical form of grilles for partitions, panels or sliding doors. . GILBERTS Head Office and Works Gilberts FB Series provides a compact, efficient range of intumescent fire dampers designed to satisfy all types of air transfer application in offices, shops, schools, hospitals and many other commercial projects. Type NV6 Vision proof langed grille suitable for surface mounting onto doors, wall or. Available in either steel or aluminum construction with either single or double flange frame options. The aluminium ‘V’ shape chevron blade mounted on a close 8mm pitch renders see through vision impossible and when double banked in a matt Grille Options & Accessories. Save4. Overall Face Height = Specified Door Opening + 1 34 3 3 9 16 XG-DGDFSS - Surface Mount Face View Neck Size MinMax Width448 Depth448 Greenheck Fan CorporationP. Our Acoustic Transfer Grilles are available in a range of sizes and finishes to suit your requirements. In the event of an alarm condition, or power failure, the dampers shut, preventing the passage of cold smoke. Technical support: [email protected]. With. Every intumescent grille contains a moisture-resistant intumescent core held in a galvanised steel frame for security and long-lasting use. 1 Double Defl ection Grille AUR 6 1. Door, Wall & Partition. For example an air transfer grille tested only in a masonry wall or duct termini is not necessarily acceptable for installation in fire doors. 54 KB: Preview: waterloo-air-products-plc_ns-non-vision-transfer-grilles_photo_1_a22cec27-d4cd-42c6-aff5-75aabd21432a. Because transfer grilles connect two rooms or a room and a hallway, there is nothing that is blocking sound between the two areas. Canadian iron main entrance doors gate grill design single door $35. Now I am down to the transfer grille or the jumper duct. There are no doors - just an open stairway leading to the cold air return upstairs? I'm considering converting one of the transfer grille to a cold air return if needed - although hoping I don't need to do the extra work if not needed! Attachments. DSR units may be used in series to increase transmission loss. Nailor 51DG and 61DG Series Door Grilles are designed to be completely sight proof and unobtrusive in appearance. From the family garage to 70,000 square feet today. Stainless Steel Door Grille with Single Flat Frame (Auxiliary Frame, Dual Core) The 9700 series transfer grilles are designed to ensure visual privacy while providing air circulation from one area to another. Air Flow : 21 m3/h. LOUVRES. James Gilbert & Son specialises in high quality decorative metalwork. ft. 0006 0. Blades are chevron in configreation and are mounted in a fixed position ina rigid PVC track in an integral part of the frame. Skip to content The IFD-D intumescent door grille kit is suitable for new or existing Proprietary fire resistant doorsets that may require air transfer or pressure relief. The ATG/BF comes complete with mounting flange plus a loose telescopic rear flange to suit a minimum thickness of 42mm up to a maximum thickness of 110mm door or partition. 98 -9%. pattern: vision proof inverted ‘v’ shape horizontal cross section blades arranged to overlap each other. recent projects include: Harrow Crown Courts Walton Prison (Segregation.