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. It adjusts to suit a door thickness from 1-3/8" to 1-7/8". 200. 008 0. Non-Vision Transfer Grilles Single & Double CoresType DTG/WTG Core Only. ) Ak Factor Core Velocity Velocity Pressure Neg. 1H 1V 2H 2V. Carnes also offers a line of Door/Transfer Grilles to allow airflow from one area to the next while maintaining privacy with Light Tight construction. AG20 Bar Grille. ArchiExpo offers ventilation grates and transfer grilles in aluminum, steel, stainless steel and other materials. Floor diffusers. Domestic Warm Air Heating Grilles. Domestic Warm Air Heating Grilles. Actuator (location varies) 8. The problem is that sound (and a small amount of light) pass freely through the vents negating all privacy of closing the door. Transfer Grilles offer the largest free area possible with the option of a sight-proof or light-proof core. 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. 6" Inch Door Air Vent Grille Two Sided Ventilation Cover - White - Overflow Ventilation Grill - Door Vent Cover -. 010Security Grilles Direct have fitted window protection for commercial sectors such as retail organisations, IT companies and schools, providing effective deterrents against potential intruders. Gilberts Non-Vision Louvred Grille | Air Transfer Grille Cover. Allows for air transfer through doors or walls. Maybe you can have transfer grilles installed to those rooms verse ducted returns. We are also able to custom fabricate products to suit your specific architectural requirements. Transfer grilles shall use 50 square inches (of grille area) to 100 cfm. Series GP Security Grilles. See the crime statistics in your area here. Send us a messageDG-3 - Double Flange Door/Transfer Grille. 10 Wigford Road Masons Mill Pietermaritzburg Tel. Door undercuts are often obstructed by carpets further reducing return pathways. 0006 0. 7 Curved Blade Register ACB 29 1. 4 Return Air Grille ARG 19 1. New Fire Resistant Door Hardware brochure. THE name in air distribution products, providing engineered solutions to air distribution projects for over 60 years. 0 ( 0) From £45. 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. Countersunk holes. Uniclass Code : Pr_70_65_04_03. Our combined intumescent fire & smoke air transfer grilles can be used in applications where cold smoke containment is required. Supply you have the fan to move air the returns are all low air pressure and do not work as well. Series FB Air Transfer Grille. 6 SERIES GP Security Grilles 150 200 250 300 400 500 600 PIVOT LINE GRILLE HEIGHT - mm ALTERNATIVE SIZE FROM PIVOT 150 POINT 200 250 300 400 500 600 GRILLE WIDTH - mm 100 50 40 30 20 10 5 4 3 2. to return. Our range of combined intumescent fire + smoke air transfer grilles can be used in all applications where cold smoke containment is required. Available Accessories 3. 4. Series L Linear Bar Grilles. 012. H Nominal grille heigh t. 5mm Pitch Neck Size = List Height - 15 50mm Opening Size = List Width x Height Introduction Gilberts SS-GE Series provides a comprehensive range of stainless steel Eggcrate type grilles to suit all types of extractTRANSFER (OR) DOOR GRILLES TRANSFER GRILLES TECNALCO 4 DGT-1 DGT-2 Engineering and Performance Data Transfer Grilles The tabulated performance data includes Volume of air, Area factor and Discharge velocity. 6171Revision: Date: Units: Page: Model: ® OF Submittal: XG-DGDFSS Stainless Door Grilles Door. Steel Maximum Security Suicide Deterrent Grille. Aluminum Construction. NR Ratings and Core Areas Air Volume m3/s Face. 7" x 3. This gives good room ventilation as a result of mixed ventilation. wait: 1 min. 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 contentThe IFD-D intumescent door grille kit is suitable for new or existing Proprietary fire resistant doorsets that may require air transfer or pressure relief. 170 in stock for next day delivery. 452 likes. IMG_0186. DSR units may be used in series to increase transmission loss. Non-vision air transfer grilles, made of aluminium, with fixed horizontal blades. Door and Transfer Grilles Allows for air transfer through doors or walls. PERFORMANCE DATA STG Core Area (sq. Returns are complicated much more so that the supplies. NV1 Grille. Single Deflection grille with horizontal fixed vanes. 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. CERTIFICATIONS. 6 SERIES GP Security Grilles 150 200 250 300 400 500 600 PIVOT LINE GRILLE HEIGHT - mm ALTERNATIVE SIZE FROM PIVOT 150 POINT 200 250 300 400 500 600 GRILLE WIDTH - mm 100 50 40 30 20 10 5 4 3 2. The LVN20S provides a unique solution to the problem of containing both fire + smoke in emergency conditions yet offering good air transfer through doors in everyday use. Also, if the crawlspace access door is left open, it may not be discovered for some time. London’s Decorative Metalwork and Metal Grille Specialist. The transfer grill comes in 2 halves and is flexible as it is aluminum similiar to duct work. Introduction<br /> <strong>Gilberts</strong> FB700 Series presents a range of Mild Steel<br /> Louvred Grilles designed to satisfy all types of air transfer<br />. - Quality 0. The sight–proof blade configuration and unobtrusive appearance make Krueger’s 9700 series grille an ideal choice for wall or door air transfer from room to room. - Economic Stock Availablity. Mm Craft Mill Finish Designer Ss Door Grill, For Home ₹ 1,050/ Square Feet. press machinery and production techniques the FB700 is<br />. Door grilles provide visual security and limits light while allowing air transfer through doors or walls. 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. Gilberts (Blackpool) limited is one of the largest UK manufacturers of Grilles, Diffusers, Louvres, Smoke/Fire Dampers and Natural Ventilation Systems for the Heating, Ventilating and Air Conditioning industry. Envirograf Firoblok | Intumescent Sleeve for Services - Silver, 360 X 204 X 60mm. Operation: The units are operated by a 24V DC electrical supply. 002 0. A transfer grille or grate is a panel or fitting with an opening allowing air or sound to move from one room to another. 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. With high quality and competitive pricing these grilles form the back bone of a standard offering that will meet any application requirements. HVAC OV 17. Our intumescent grilles and fire dampers combine air movement with fire protection. The 2 most practical options are soundproof blankets and soundproof curtains. The DGC is manufactured as per the DG but in a channel frame. NV3 is a Vision proof core in 32mm flanged border with matching telescopic back flange. We can supply vents in a bespoke design to suit your requirements. Aluminum Construction. Available in nominal 2" (51) increments. 005 150. Air Ventilation Grilles, Fixed Blade & Adjustable Louvres, Ventilation Diffusers, Air Supply & Air Exhaust Valves, HVAC Grilles, Air Security Grilles, VAV & CAV Units, Radiant Panels and Trench Heating supplies from the industries leading manufacturer. The Perfect Balance In-Door Return Air Pathway is a grille installed into the bottom. Pyrogrille air transfer grille allows free air flow and provides up to 60 minutes fire protection. 5m/s and NC level less than 15. Volume dampers or other means of supply air adjustment shall be provided in the branch ducts or at each individual duct register, grille or diffuser. Aluminum door grilles. Designed for. Grille face made of aluminium with anodised finish 30 mm wide front border Countersunk holes Optional equipment and accessories Grille face in RAL CLASSIC colours Installation subframe Matching rear frame for door installation. Blades are chevron in configreation and are mounted in a fixed position ina rigid PVC track in an integral part of the frame. Nailor 51DG and 61DG Series Door Grilles are designed to be completely sight proof and unobtrusive in appearance. Alternatively, secure the system using self-tapping screws. e. One grille is located high on the wall on. Applications. Uniclass Code : Pr_70_65_04_03. Learn More > Hushon UK Ltd. From the family garage to 70,000 square feet today. 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. frame: telescopic frame suitable for doors or partitions from 25 – 55 mm thickness (fixed on both sides of the door) material: extruded aluminium profile for frame and blades: sizes:Above door transfer grilles. Designed for door mounting. ) 0. Visit the Quietcool Store. Model DG-FC Louvre Grilles are available in stock sizes and can. Suitable for use in doors, walls or partitions the dampers are fabricated from thin Our range includes circular cast louvres, which are ideal for bathroom extractor fans, penthouse/turret weather louvres for roof mounted ventilation, weather louvre cladding for easy assembly on-site. 4. ft. Jet diffusers. 020 inch water column) is acceptable for rooms with a design airflow ≥150 cfm. Catalog. Height : 1005 mm. Adjustable from 1-3/8" to 2 1/4" door thickness. Volume Control DampersStandard and large format air volume control dampers for ducted air systems. Any guidance the committee could provide in this area would be most helpful. Our grilles have high quality paint finishes and accessories to suit your individual requirements. . TROX Services. 57 (29 grilles required) 0. Both the Halton TVC grille and opposite frame are screwed to the wall or door. 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. Program. HVAC OV 17. 3. air transfer grilles can be used in all applications where cold smoke containment is required. For both fire and smoke protection, see the Lorient LVN20S Air Transfer Grille. It's annoying that you can hear everything that goes on in the house due to the transfer grilles above the door. Install the Air Transfer Grille into the aperture. #2 · Sep 12, 2012. uk . Because transfer grilles connect two rooms or a room and a hallway, there is nothing that is blocking sound between the two areas. A. 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. In the event of an alarm condition, or power failure, the smoke shutters shut, preventing the passage of cold smoke. g. 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. My question is, can you essentially install a duct from the location of the grille, to somewhere else inside the house? (for instance down a hallway, it will still have a vent for air return, just moving that away from my actual. NV1 is the Vision proof core only. Introduction 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. 5mm. The Perfect Balance is a transfer grill designed to fit in the door. This is partly due to a privacy issue. 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. In many cases, pipes and ducts. One grille is located high on the wall on. Door, Wall & Partition. Introduction. Our Acoustic Transfer Grilles are available in a range of sizes and finishes to suit your requirements. transfer grills over doors to bedroom/office. 65mm thick Zintec mild steel with Zintec clips. 5 inches (38 mm) or the closet shall include a louvered door or transfer grille with a minimum net free area of 30 square inches (194 cm 2). 175m3/sGilberts’ NV/6 non vision transfer grilles are surface mounted into doors and blockwork, allowing the passage of air and light whilst obscuring vision, whilst the Smokeguard dampers allow ventilation view a drive mechanism that enables airflow in normal circumstances, closing to prevent smoke and flame penetration in the event of a fire. Door Transfer Grille Ordering Specification Sizing Finish Introduction Gilberts AV1601 Series presents an attractive alternative to traditional vision proof door mounting air transfer grilles. Introduction Gilberts AV1601 Series presents an attractive alternative to traditional vision proof door mounting air transfer grilles. Favorite. 20 Patterson Brook Road – Suite #7 West Wareham, MA. FGS - fire resistant and cold smoke control mechanical air transfer grille (type MMS) are designed and certified in accordance with EN 1364-1 and ETAG 026 part 4,View Our Presentation. 2. And with an experienced team of Sales. Nominal sizes 150 × 105 – 1500 × 985 mm. We are the world's oldest manufacturer of decorative metal grilles. Grille face made of aluminium with anodised finish. Polyaire Product Catalogue - Door Relief Grille. EI rating of 120 minutes when used. uk HomeDoor grilles are seldom used nowadays for two reasons 1. The Perfect Balance and Return Air Pathways. Door Furniture; Drawers and Drawer Runners; Eyes; Feet; Fixings Fasteners; Formed Section; Gastronorm Containers; Gates; Glass Canopy; Handles. duct or transfer grille), and perimeter walls insulated in accordance with Section N1102. Also, there is NO indication of the how to determine the required size of the permanent openings of any type. Countersunk holes. Ventilation grille with angled blades. Model DG-FC Louvre Grilles are available in stock sizes and can. Displacement diffusers. A collection of intumescent air transfer grilles offering protection against fire. We are the world's oldest manufacturer of decorative metal grilles. Gilberts are a local, trustworthy company based in Gosport who have been offering a wide range of services. NV2: As NV1 but with a spare backing frame for fitting into doors. robustly fabricated from 20swg mild steel and comprises of<br />. Series PE Perforated Face Extract Grilles. Smoke, Fire and Volume Control. Minimum size is 6" x 4" (152 x 102). 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. Door / Transfer Grilles Products Matching Your Selection METALAIRE is the flagship brand of Metal Industries Inc. December 19, 2020 ·. 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. Air Flow : 21 m3/h. 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. All manufactured from 1. James Gilbert & Son specialises in high quality decorative metalwork. ALN, ALM, ALF, ALG, ALJ Airline Linear Grilles 14 APF, APG, APJ, APN, APM Plasterline Linear Grilles 16 UC / UF / UE Urban Grilles 17 Door / Sidewall Grilles NS, DV, NSNL Air Transfer Grilles 18 DSR, DSRX Acoustic Air Transfer Grilles 19 T P W Ss e l l i r G l l a w e d i 20 WFV, WFVG Fire Rated Air Transfer Grilles 21 Floor GrillesWaterloo transfer Grilles are suitable for mounting in doors, partitions and Walls to allow ventilation air to pass between adjacent rooms. Acoustic, smoke + fire containment systems. Save4. With a class leading range that includes a mix of both leading edge & traditional designs, as well as standard or bespoke, we have the product to suit your project and your budget. £7. To contact us please call: +44 1253 766911. Gilberts FB700 Series presents a range of Mild Steel Louvred Grilles designed to satisfy all types of air transfer application in offices, shops, schools, hospitals and many other. Air Flow : 21 m3/h. Single & Double Deflection Grilles. AG40 Bar Grille. TYPE GPS3 & GPP3 -Air transfer grille arrangement comprising of a high security bolt fixing unit on one side and a lower security clutch screw unit on the other. The units, which satisfy BS 476 Part 22, incorporate intumescent elements which expand and carbonise when exposed to temperatures in excess of 150 C, thereby sealing off the ventilation opening. O. Series AV Door Transfer Grille. View Product. Showing 11 of 122 products. The face velocity through return grilles with 'V'core should not exceed 2m/s. 006 0. Both the Halton TVC grille and opposite frame are screwed to the wall or door. 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 . Aluminum door return grille with sight-proof blades parallel to short dimension. ft. The frames are of 0. heating and cooling load) calculations typically yield the airflow requirements to the various rooms to meet those design loads. 001. Bespoke designs, priority order and guaranteed delivery dates. 11 of this code. 54 KB: Preview: waterloo-air-products-plc_ns-non-vision-transfer-grilles_photo_1_a22cec27-d4cd-42c6-aff5-75aabd21432a. Pressure drops for ‘L’ core include entrance loss as well as resistance due to two cores placed side to side. Gilberts Blackpool. Blades are chevron in configreation and are mounted in a fixed position ina rigid PVC track in an integral part of the frame. Door/Transfer Grilles. The grilles are carefully constructed to be unobtrusive in appearance for architectural excellence. 8 m 2), the closet door shall be undercut a minimum of 1. Where was Gilles Gilbert born? Gilles Gilbert was born in St-Esprit, Canada. 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. LVH20S intumescent fire + smokeThe Ligature Resistant Retrofit Exhaust/Supply Grille is designed to replace existing grilles that are not ligature resistant. Transfer units. Width : 1025 mm. Available in either steel or aluminum construction with either single or double flange frame options. These are particularly suitable for doors to staircases etc. Air volume q v: Discharge velocity V k : Outlet size : Effective Pressure Area A k : Air volumes are given in mt3 / sec. Door Transfer Grilles. The damper can be suitably masked on both sides either with steel type A grilles or aluminium non-vision type B grilles. Catalogue DIFFUSER. dimensions: 788 x 788 mm H • Fitting dimensions: 7 mm more than the grille dimensions. They can be used for providing dampers in ductwork. Designed to be fitted in doors, walls and ducts they provide a cost effective solution in allowing free air movement and yet maintain the integrity of the door or wall in a fire situation. Single Core with Flat Frame. co. 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. 5 to 92 mm. Static Pressure 100. Reliable. co. Door controls. DL. Inverted V type grille bar for best vision proof quality and airflow. For Enquiries contact us on +44 (0)1384 376555; Recently viewed items ;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. 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. Air Distribution | GDL Air Systems Limited | England ATG. The only place I can install transfer grilles is above the doors. ) 0. Minimum size is 6" x 4" (152 x 102). It's annoying that you can hear everything that goes on in the house due to the transfer grilles above the door. 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. Transfer grilles are designed for use in doors and partitions to allow for smooth transfer of air between spaces. Lorient offers a range of cover grilles for its intumescent air transfer grilles. NV1 Grille. Series GECA-RC Removable Core Eggcrate Grilles. 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. 001. Login / Register; 0117 9372846;. Shop our great collection of registers & grilles at everyday low prices. LVH20S intumescent fire + smokeAcoustic Transfer Grilles DSR Acoustic transfer grille DSRX Acoustic transfer grille for variable depth DSR2 Back to back acoustic transfer grille. 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. - Wide 33mm Flange Border. 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. ; Transfer grilles shall use 50 square inches (of grille area) to 100 cfm (of. Door, Wall or Partition Mounting. uk. Domestic Warm Air Heating Grilles. In the event of an alarm condition, or power failure, the dampers shut, preventing the passage of cold smoke. Length : 80 mm. Allows air to flow freely between spaces. Steel Maximum Security Grille with Square Perforations. 81 + VAT. Model includes a v-shaped louver providing a sightproof return or exhaust grille regardless of the viewing angle. Easy to assemble. 51DG 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. 5. 004. 5 to 6m x 1m, and each RAL coated to 7047, provide discreet, passive ventilation to the rooftop plant. ) Nominal Size Core Velocity (fpm) 100 150 200 250 300 350 400 Velocity Pressure (in. AG10 Bar Grille. 005 150. Mar 23 2021. 14 (58 grilles required) 0. Begin by selecting a space over a doorway and measure the metal frame. supplied by Gilberts with each Grille batch. ft. other commercial projects. Lorient Intumescent Air Transfer Grilles are suitable for ventilation in fire compartment walls or doors. BBB Start with Trust ®. Engera Bathroom Door Air Vent Grille Two Sided Ventilation Cover for Restroom, Warehouse, Storage Doors | Interior Door Transfer Grill 453mm x 91mm (18. . Those results will be discussed in a future report. 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. Individual grilles, grille bands, multiple grilles, and long throw nozzle grilles achieve different throw distances. Door grilles are required for the transfer of air from one room to another Material Door grille manufactured from. <br><br>The Perfect Balance In-Door Return Air Pathway is designed to maintain adequate air flow between rooms and eliminate pressure imbalancesallowing each room. Door / Transfer Grille Extruded Aluminum 10/19/2022 Inches 1 1 DGSF Single Flange Frame 1. Browse a range of intumescent vents also known as air transfer grilles and fire vents. Reinforced terminals. Return/Exhaust/Transfer Air. - Attractive Slimline Appearance. 02576. 1 (7 reviews) Extruded aluminum grille supply. (Matt black finish). VIEW XG-DG Series. A high performance, standard vision intumescent air transfer grille for walls, doors and ventilation ducts. Duct Smoke/Fire DampersCombined smoke and fire damperssuitable for use in all types of HVAC ductwork. 01924 444 174 sales@briteair. when doors are open. Duct diffusers. 603. 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. See the brief list at the end of some suitable grilles. DESCRIPTION: Construction: Frame and blades are 6063 extruded aluminum alloy with 200-R1 satin anodized finish. 0006 0. A range. It adjusts to suit a door thickness from 1-3/8" to 1-7/8". 0 ( 0) From £4. We can supply vents in a bespoke design to suit your requirements. TRH-A series grilles have a simple design which makes them useful for incorporation in all styles of architecture. Long throw, high capacity supply grille with rotating drum. Battic Door 20 Patterson Brook Road – Suite #7 West Wareham, MA. 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. 25. The LVH44 dampers can be assembled in multi-modules to protect large. A definitive guide to operating theatre diffuser selection in accordance with HTM-03-01. Type NV6 Vision proof langed grille suitable for surface mounting onto doors, wall or. The Waterloo fire rated ventilators are suitable for 1 hour rated doors and partitions. Manufacturer : Madel. NV6 is a Vision proof flanged grille suitable for surface mounting onto doors, wall or partitions. 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. Series GAwith a door sleeve and electrical door wiring loop for a 45mm or 54mm door or a wall sleeve only, for a wall/partition. A door undercut is a space between the door and the floor below it that’s large enough to allow air transfer between rooms. Door grilles provide visual security and limits light while allowing air transfer through doors or walls. grilles, ducts Brackets: remove, box in or chase into wall Grilles: perforations should be a maximum of 3mm in diameter. Enter SIte. 61EC - Steel Frame, Eggcrate. Lorient Intumescent Air Transfer Grilles are used to provide an answer to situations where ventilation is required in fire compartment walls or doors. H Nominal grille heigh t.