Offline System AttenuationHere’s a summary of the regulations for the installation of soakaway crates: Should be located at least 5 metres from the wall of any building. Carlow Concrete are one of the leading specialists in Stormwater Attenuation in both the UK and Ireland. 3 StormCrates per 1m³ storage capacity • Lightweight and easy to install in up to 10 layers • High strength crate with lorry bearing of up to 60 tonnesAt Moore Concrete we can design and install this product based on your desired needs and specifications. A few pointers are noted as follows:EcoBloc Flex is a modular geocellular unit which is used as a below ground stormwater attenuation or soakaway tank. We recommend that your groundwork contractor undertakes a percolation test on your soil to calculate the correct number of. It enables engineers to create a blue or green roof drainage layer that gives architects the design flexibility required to create imaginative, multi-functional open. The CORE WATER crate is a step forward in drainage technology; advancing from the old-fashioned, inefficient soakways filled with hardcore and building waste, the crate provides a safe and intelligent solution to rainwater management. Rainsmart's Terravault is a modular cellular confinement crate system that protects tree roots from both vehicular and foot traffic. Attenuation crates work using a very simple process, very much in a similar way to attenuation tanks. • Project Explore, Steetley - Attenuation Pond Lining (15,000m²) Stormwater Management Limited Fleming Road Harrowbrook Ind Est Hinckley Leicestershire LE10 3DU Tel: 01455 502222 Fax: 01455 502223 Email: sales@storm. Maximum installation depth of 4m. 99 GBP. The system has an exceptionally high compressive and tensile strength and bending resistance with a proprietary. Attenuation. 4m (400 litres/0. 5m x 0. Ireland: +353 (0)14378831. 25 metres. Attenuation Tanks. Increase in linear attenuation coefficients was observed, showing that changing crystal structure changes linear attenuation coefficient of a material. VAT. FREE delivery 8 - 9 Nov. The modular cells combine to provide water storage structures to help with localised flood. noun. Add to Compare. The rigid crates are made in black polypropylene (PP) and measure 1200mm (l) x 600mm (w) x 420mm (h) and will hold a maximum capacity of 300 litres gross or a working volume of 285 litres. This enables Polypipe to supply fully integrated below ground drainage elements, which may be composed of a number of differing systems, each chosen to suit the proposed location. Access for inspection and maintenance is via Stormbloc ® Inspect. Water directly impacts us and our planet’s ecosystem. Find out below some of the innovative ways engineers, contractors and local authorities have designed, installed and maintained StormBrixx solutions in unique configurations including the narrow verge-side. 17. Dimensions: 1000mm x 500mm x. see more. 300 to +. At present FreeFlush is proud to brought two Soakaway crate alternative, comprising two models of Rainwater Soakaway Attenuation Crate Packages. attenuation; axe; boil; contraction; damp; fall off; fall off a cliff idiom; falling; falling-off; foreshorten; rightsizing; roll back something; rollback; run someone/something down;. Explore our wide range of durable and efficient products and make your selection today. Features & Benefits: Graf Rain Bloc Stormwater Attenuation Crate - 3. Inc. This below ground Rain Bloc crate is a simple an effective way to form a Soakaway or attenuation tank. ON BACK ORDER - Please contact us for availability and alternatives. Designing attenuation storage for redeveloped sites The authors This factsheet has been prepared by Anthony McCloy of McCloy Consulting. If purchasing in bulk give us a call so we can offer you the best price. The crates are manufactured from durable plastic which clip together easily to form a box structure. 3 Crates per m3, 60 Tonne Rated. 19m3 per crate. Add to basket. This crate is supplied with 4 x clips F. Add to Compare. Description. As part of a heavy water or. £60. Select the right Modular Cell. The attenuation coefficient, backscatter term, and the image intensity are further analyzed in regions of interest, which have been delineated referring to their pathology counterparts. Stormbloc ® Extra. 11. 00 £68. Effective stormwater attenuation relies on the ability of a product to trap and store. Soakaway Crates: AquaCell Core-R 60 Tonne Wavin Soakaway Crate - 200 Litres. 30. Efficient pallet stacking provides quick construction and installation. Visual and maintenance access can be achieved when used in conjunction with Polystorm Access & Polystorm Inspect. Flooding can cause significant financial losses and damage. Account. Rated 5 out of 5 stars. The key element is a flow control chamber to regulate the amount of water. Stormwater Management Brett Martin’s StormCrate55 modular cellular crates are used in storm water retention, attenuation and infiltration applications. £204. Ordered terram t1000 Good price Good communication Delivered on time Would recommend. Buy it now. This crate has a compressive strengh of 61 tonnes/ m2. The inlets/outlets are located in different positions and the crate structure fills when the flow rates exceeds the agreed discharge rate. 2018 various@a3 do not scale - if in doubt ask this document is supplied in strict confidence and must not be lent, reproduced or disclosed to any third party without the written consent of graf uk limited notes:-Permavoid. Attenuation Tanks. Brett Martin Storm Crate 55 Tonne 1200mm x 600mm x 347mm (0. 00 10,000 litre SuDS Rainwater Attenuation Tank with integrated flow regulator. Inc. 90. Attenuation Tanks are preferred over alternative methods such as soakaway crates. High compressive strength – can be located under all roads,Rain Bloc 60 Tonne Soakaway and Attenuation Crate - 0. 00 each. Incredibly strong and durable modular polypropylene construction. This product can bear up to 62 tonnes and is 1m x 0. 00 £68. The collected storm water then drains away slowly into the drainage system when the crate is used for attenuation, or, soaks away slowly into ground water table when the crate is used for infiltration. It can also be a useful way of harvesting water for other uses such as gardening, car washing and toilet flushing. 65 Incl. An attenuation tank is used to capture surface water run-off that occurs during prolonged periods of rain, reducing the risk of localised flooding. The key difference is the lack of impermeable geomembrane liner. Number of Rainsmart Ellipse Double Crates Required:. Our industry leading products can be deployed in Infiltration / Soak-away, Permeable and Impermeable Attenuation systems, which makes their range of applications incredibly. 5m x 0. 3 Cubic Metre . 82’ (800 x 490 x 250mm) Material: 100% Recycled PP, or Virgin Materials Load Capacity: 40T/m2 Tanks: 10 tanks/cbm Void ratio: 94% Water Storage:. Buy Polypipe Polystorm R (PSM1A) Soakaway Crate / Attenuation Cell Online at an Amazing Low Price From Easymerchant. Hydrocell soakaway crates are used in soakaways, stormwater retention, attenuation or infiltration applications. The ability of a medium to attenuate sound waves at a given frequency is called its attenuation coefficient (denoted by the Greek letter alpha (α). Register | Login. 54 Excl. This below ground Rain Bloc crate is a simple an effective way to form a Soakaway or attenuation tank. This removes the. The Wavin Core-R Modular Unit is part of the AquaCell range of geocellular systems that is a fully tried and tested, BBA approved, modular technique for managing excessive rainfall. Ecomerchant Aquacrate is designed for the storage (attenuation) of stormwater in both attenuation and infiltration schemes. A robust yet lightweight soak-away solution that gives the product a long life as well as making yours easier when it comes to installation. Weight. See the illustration. Underground storage requires a lot of strategic planning to accommodate the many infrastructures that are already in place (piping/cables etc. Both are used to create a geocellular interlocking system designed for shallow groundwater storage or infiltration, replacing the traditional aggregate sub-base. JFC’s Attenuation Water Management solutions help control the rate at which water enters the watercourse or storm drain. . 03. Soakaway & Attenuation Crates Silt Filter Chambers Stormwater Attenuation Tanks. ACO RainDrain Channel and Galvanised Grating A 15 - 118mm x 97mm x 1000mm. Rain Bloc Stormwater Attenuation/Soakaway Crate. Crate size 1200mm (L) x 600mm (W) x 420mm (D) (3. Modern attenuation crates offer more flexibility when it comes to installation. 50 each. To work this out measure the areas your property covers consisting of the external hard surfaces — such as roofs and garages down towards your patios, driveway and paths. 00 Graf Infiltration Tunnel Kit for Soakaways, Attenuation and Wastewaster. Compressive Strength: Maximum 55 Tonne. 99 (£37. It can be easily installed without heavy machinery one EcoBloc Inspect flex module weighs just 8 kg. Brett Martin has provided its StormCrate55 modular crates for an underground attenuation tank designed to control stormwater and address excessive rainwater run-off as part of a prestigious development of homes in central Scotland. Add to Compare. Product Description. £103. 2m3 per crate. 300 to +. Experts recommend that the bedrock should not be within one metre of the drainage piping, in order to maintain proper filtration levels. Description. £54588. Our soakaway crates clip together to form a load-bearing underground water storage/attenuation system. 21 inc VAT Was: £0. GEOlight® provides green residential amenities with additional run-off capacity – The Quarry, Erith. Surface water attenuation is one of the key actions to move in this direction. The plastic driveway grid, with its stability and adaptability, revolutionises the way we approach these projects. The store will not work correctly in the case when cookies are disabled. McAlpine Plastic Inlet Soakaway For Condense Drainage SOAK1GR 110mm x 300mm x 22mm. The modular cells combine to provide water storage structures to help with localised flood. VAT. Paired with quality construction supplies, it ensures a foundation that withstands the test of time. Attenuation is an intrinsic property of a medium. A stormwater attenuation system provides a cost-effective solution but not all companies have the. 49 ex VAT) Est. For both commercial and domestic properties. It has a 61 tonnes/m² compressive strength and is manufactured from over 90% recycled material content. Contact Us today 01616671241. Hydrocell Soakaway Crate 62 Ton. From £ 0. COMMERCIAL SEWAGE TREATMENT PLANTS. £69. Contact Us today 01616671241. The HydroChamber is an arched chamber attenuation system designed specifically for building underground storage tanks for stormwater runoff in attenuation and soak away applications. Its versatile design allows the system to be used in configurations and applications across all construction environments as a standalone solution or. Soakaway and Attenuation Crates PSM1A. Brett Martin Cellular Storm Water Crate 55 Tonne - 1200mm x 600mm x 347mm. Code G4110M3K; Brand Graf; £415. Please visit our Geotextile page to find out more. This is where our soakaway crates come in. Polystorm-R is designed to offer a solution in issues of surface water attenuation, surface water retention or surface water infiltration. Features & Benefits: AquaCrate Stormwater Soakaway and Attenuation Crate 20 Tonne - 2. A soakaway crate is designed to send water into the soil, while an attenuation tank stores and redirects it to a watercourse (river, lake or reservoir). Install IBRAN Gravel Grids for assured quality, consistency and confidence. The level of released water must be calculated to flow at the correct rate as this. What is the difference between a soakaway and an attenuation tank? A soakaway, as the name. Hewitech design, manufacture and install Attenuation tanks. Out of Stock. It allows rainwater run-off to be temporarily stored and then released gradually. 8')Even under very heavy loads, GRAF EcoBloc Inspect flex modules can be installed at a depth of. All penetrations are sealed to ensure one-hundred-percent waterproofing integrity, using stainless-steel bands or special components provided by the crate/block Manufacturer. The modular cells combine to provide water storage structures to help with localised flood. If the CTAC could be used for calcium scoring, the acquisition of CSCT scan could be omitted, which would decrease the radiation dose to the patient and increase time and cost. These. Engineered from top-tier recycled polypropylene, this module boasts exceptional strength and remarkable water permeability while offering an expansive storage capacity. Stormwater Attenuation Crates for Stormwater Attenuation Tank System. The Polystorm geocellular range is ideally suited to deeper applications and can accommodate a wide range of traffic loadings, from pedestrianised areas to large HGV parks. Soakaway crates can be used for rainwater attenuation or soakaway purposes in commercial and domestic projects. This top hat connects to JFC CorriPipe twinwall drainage pipe. It is ideal for source control and surface water treatment applications, and can easily overcome problematic site conditions such as high. excl VAT (Each. A system of 60 attenuation crates, stacked 400mm high, is capable of storing 11,500 litres of water and can withstand up to 62t/sq m of weight above. Rainsmart Ellipse Soakaway Crate. The EcoBloc Flex crates are designed to be stacked together to create a holding tank or to allow the infiltration of storm water into the ground. Attenuation Tanks. It can be easily installed without heavy machinery one EcoBloc Inspect flex module weighs just 8. Polypipe Civils Charnwood Business Park, Loughborough, Leicestershire LE11 1LE Tel: +44 (0) 1509 615100 Fax: +44 (0) 1509 610215 Email: civils@polypipe. Product Details. Anthony is a Chartered Civil Engineer with considerable experience in water, hydrology, flood risk and drainage, particularly in relation to SuDS design and hydraulic modelling. 00. 40 Save 20% . If you live close. View details. The crates are ideal for soakaways and attenuation tanks specified by planning and building control. (1) From £ 0. IBRABASE Plastic Grids. It's. 42m3 StormBrixx crates (in four pieces) 8 x side panels for lateral support. Open an account E-Billing Sustainability About Help Contact us. 5kg. These soakaway crates (Polystorm) clip together to form a load-bearing underground water storage/attenuation system. An online attenuation system means the total volume of rainwater passes through the crate structure. Our skilled site crews offer many years installation experience with a wide range of attenuation tank units including Aquacell, Graf and Polystorm. Rainwater Soakaway Attenuation Crate Package - EcoBloc Maxx is one excellent option using which you can stock water either for own use or release the same later based on your choice and requirement. Soakaways are generally designed for small usage, like isolated residential properties and permeable ground conditions, like sand or gravel. Rated 5. In contrast to soakaway crates, which allow rainwater to directly soak back into the soil, attenuation tanks temporarily store rainwater during a heavy spell of rainfall and release it at a controlled rate into drainage systems or a natural body of water. Easy to assemble and install. The StormMaster Heavy Duty Crate is suitable for car parks, general duty and traffic use. The AquaCrate decreases the inconvenience of flooding during heavy rainfall, with rainwater “cleaned” by the geotextile surround. Latest Case Study: Severn Trent Water Following an evaluation from the New Products CoP Group Waste team of Severn Trent the stormwater management system by Triton Stormwater Solutions has been approved for use within Severn Trent on both AMP 6 Capital Projects and Developer Sites. Shop our collection of soakaway crates, attenuation crates & tanks here today from reputable brands like Aquacrate, Polypipe, Graf, Marsh Industries & more!. The Polystorm geocelluar system can also be integrated with Permavoid systems. Step 2 – Prepare the crates. Stackable stormwater attenuation crates offer a modular design that give you more flexibility over how the system is installed and set-up in the ground. Use the look up table to select the number of crates required using the Nett volume per crate (0. Soakaway / Attenuation inspection and maintenance. weakening in force or intensity. Easy to handle and install. The crates are a single piece and can be easily maneuvered, stacked and placed. Features & Benefits: Storage capacity of 290 litres. Soakaway crates can be used for rainwater attenuation or soakaway purposes in commercial and domestic projects. Rainwater Diffuser: The rainwater diffuser collects surface water into the voided subsoil aggregate in a permeable or impermeable infiltration system. g. Designing a Crate System for Attenuation. 5. One of the key benefits of this type of system is the modular construction, which allows multiple crates to be built to suit the immediate environment. Select the right Modular Cell Polystorm Lite – PSM2 Polystorm Lite has been specifically designed for non-trafficked applications. DOMESTIC SEWAGE TREATMENT PLANTS. 4 crates and would require 750mm of cover for traffic or 500mm for non-traffic use. 84 ex VAT £2. The effects of climate change are creating an unprecedented demand for Sustainable urban Drainage Systems (SuDS). The crates are designed to be easily stacked together to create a below ground storm water holding. g. ALL. Each soakaway crate is a different size, therefore the brand you choose can determine the number of crates required for your attenuation system. 00 ex VAT. For attenuation systems: Position the inflow and outflow connections level with the base of the Aquavoid-Metro structure. Simple and quick installation method. Quantity: 25 Year Guarantee. If creating a larger soakaway through butting and stacking, we recommend connecting using cable ties until the side fill is introduced. 3 Cubic Metre . synonyms: fading. Code G4110SC; £45. Integrated inlet and outlet. Our crates are a step forward in drainage technology; advancing from the old-fashioned, ine˛cient soakways ˚lledA flow straightener can be a tube bundle or an “egg crate,” as shown in Fig. Durable and long-lasting. If you have a special requirement or any questions, please contact us on 01430 430 529 or email enquiries@gwapipes. O. excl VAT (Each) Buy Now. 50 each. Crates come in different strengths. The high void rate (>95%), high compressive strength (to 1000KN/m2) and low resistance to water flow makes SDS GEOlight® an ideal material for cost efficient and maintainable underground water storage during storm conditions. George Bethell, Largest range of Soakaway Crates and Attenuation Cells for Drainage in the UK. With a 20 tonne per square metre compressive strength it willWhat are the different types of attenuation crates? There are several types of attenuation crates that can be used for different applications: Single piece crates. Whether we have too much or not enough, it is as much a life giving resource as it can be life threatening. 72 £57. Once installed, they are combined with a geotextile and waterproof pipework to. Rainsmart Soakaway Crate Assembled - Heavy 65 Tonne . Weight : 15. Branch locator. It can be easily installed without heavy machinery one EcoBloc Inspect flex module weighs just 8 kg. 8. from £8. Checkout. Attenuation crates need to be designed to minimize. 25m3). To build the attenuation system, the blocks are connected together into a matrix. 2m3 per crate. Following are the key types of Attenuation systems: Attenuation Pond; Large Size Attenuation Pipes; Attenuation Crates; Rainwater Diffusor. Osma Rainchannel Drainage Channel With Polypropylene Self. 99 GBP. This is provided free of charge from JDP Technical Support. 2019 various@a3 do not scale - if in doubt ask this document is supplied in strict confidence and must not be lent, reproduced or disclosed to any third party without the written consent of graf uk limited notes:-KLARGESTER AQUAHOLD - Surface Water Storage Tanks Range. From £3,669. Rain Bloc 60 Tonne Soakaway and Attenuation Set with Silt Trap & Lid - 0. Let P0 P 0 be the power at z = 0 z = 0. 4m3 per crate. So, what are the differences between stormwater storage crates for filtration and attenuation? Let’s find out. Decreases possibility of flooding during heavy rainfalls. Wavin AquaCell units are a tried and tested modular technique for managing excessive rainfall and can be assembled to create an underground structure as either a temporary attenuation tank or infiltration soakaway. attenuate: 1 v become weaker, in strength, value, or magnitude Types: refine attenuate or reduce in vigor, strength, or validity by polishing or purifying Type of: weaken become. These crates are used in a storm water management system to provide temporary storage for. COMMERCIAL SEWAGE TREATMENT PLANTS. A) CRATE SYSTEM. Depending on environment conditions and the desired storage capacity, these blocks can be installed. Easy-install, interlocking grids suitable for all garden buildings. 200 to 299. Its superior design makes it suitable for building storage tanks under HGV trafficked and car park areas as well as non-trafficked areas (e. Compatible with ACO surface water drainage, downpipes, and roof outlets. 25% Off Sold Out. Soakaway Depth. Features & Benefits: Polypipe PSM1A Polystorm Plastic Soakaway and Attenuation Crate. 12ft x 12ft. Stacked on pallets to save space during transport reducing costs and CO 2 emissions. The installation is warrantied for 30 years as the membrane is wedge welded and the joints air tested. 72 £57. If you are new to stormwater attenuation crates and are not familiar with the different types of systems that are available, it may be difficult to know where to start. Your property's total impermeable area is one of the details you would need to provide to work out how many crates you need. Faulty devices, like a wireless mouse or headset. Both are used to create a geocellular interlocking system designed for shallow groundwater storage or infiltration, replacing the traditional aggregate sub-base. The issue of water attenuation is an increasingly hot topic, with more occurrences of extreme weather patterns being experienced across the UK. The first is the base while the. GT 500 2000 gauge Impermeable Tank Line Membrane. The system facilitates quick and easy assembly on site where multiple configurations can be formed. 190L crates supplied if multiples/ larger amounts ordered e. the property of something that has been weakened or reduced in. Ex VAT Inc VAT. Storage Volume: 190L per crate. From £269. Here are the steps required for undertaking a percolation test for foul water soakaways: Excavate a hole – Dig a hole 300mm square to a depth of at least 300mm below the proposed invert, spacing them along the proposed line of the where the soakaway would be. As you. 00 £498. Q&A. Stormwater attenuation and infiltration/soakaway crates ACO StormBrixx is a unique and patented plastic geocellular stormwater management system for attenuation and soakaway (infiltration) usage. A stormwater attenuation tank is designed to collect and store excess surface water run-off from a large storm event. Quantity. RainCatcher Rain bloc infiltration and attenuation crate system - 300 litre capacity PLUS non woven geotextile for self wrap. In 1996 SDS GEOlight® helped create the foundations on which our company was built, when we completed. Polystorm and Polystorm Lite are lightweight modular water storage cells with a high void ratio that can be used for either attenuation or infiltration of stormwater in residential, commercial, industrial and retail applications. Sadly, there is little we can do to help maintain these installations. £58. Managing stormwater is becoming more and more of a challenge for builders and developers who need to meet the increasing regulation to control its flow. Add to Basket. 15), pull the geomembrane up the sides of the tank, create ‘bedsheet folds’ to the corners and tape into position. This product is designed for below-ground. 00. The void in the crate holds the stormwater during heavy ra. VAT. Documentation. Fig. Not only are they more efficient with a larger void capacity (95%) they also have superior structural integrity. Joining as many crates together as required in order to achieve the specified void. DOMESTIC SEWAGE TREATMENT. From £269. This allows any construction site to release water at a rate that drains can adequately handle, thereby preventing a flood. The void created by the crates can then. 2. Our no-nasty-surprises, easy. It can hold 0. Efficient pallet stacking provides quick construction and installation. Attenuation crates, also known as soakaway crates, are used to control the level of surface water and reduce the risk of flooding. Hydrocell Soakaway Crate 62 Ton. Contact Us. The study of attenuation is important to ensure minimal signal loss in transmission. Soakaway crates are available from our depots in Yorkshire, Cumbria and Warwickshire. 1000 x 1000 x 400mm (0. Call Us. A high-strength option ideal for installation beneath heavily loaded areas such as roads, car parks and warehouse yards. RAINBOX 3S is a geocellular crate that can be used for attenuation or soakaway purposes. Thrilled to have delivered the first instalment from our huge order of over 1000+ soakaway crates to. It is supplied fully assembled, which makes installation much easier to plan and complete. from €1,914. Geocellular crate for soakaway (infiltration) or storage (attenuation) applications for surface and storm water. Size: 2. Each crate has cut-away templates to suit all standard size pipes. Polystorm Crate. Next, scroll down to the Attenuation sections and drag the slider to 0% to disable attenuation. Stormwater attenuation tanks provide a storage system for rainwater and surface water. Stage 2 - The filtered stormwater enters the pre-built geocellular crate system at a size that will hold the required level of stormwater. 285 m3), please also consider the stacking arrangement : No. When using a crate system, be sure to level the bottom of your hole and layer it with shingle or sharp sand that’s compacted down. Complete crate weighs 11. . £44. Reviews. Compressive strength of 83 tonnes/m². Flexible shape, perfect for use in restricted areas, narrow strips or shallow excavation systems. Attenuation Rainwater, which has been collected from impermeable surfaces, is directed to the crate structureStormwater Attenuation Crates I Stormwater Attenuation Tanks I Stormwater Attenuation Lagoons. 69. 3 Cubic Metre . Documentation. So no, they serve different purposes. Spend another £1500 to pay over time with. Rain Bloc Stormwater Attenuation/Soakaway Crate. AquaCell Core-R can also be used in both landscaped and deep. 88 ex VAT. Figure 2: Insertion of attenuation lid on top of the crates. AquaCell NG is designed primarily for landscaped. A stormwater attenuation tank is designed to collect and store excess surface water run-off from a large storm event. Buy online today or call us for more information!Stormwater attenuation and infiltration tanks constructed using modular plastic geocellular units are commonly used as part of sustainable drainage and rainwater harvesting systems. Rain Bloc 60 Tonne Soakaway and Attenuation Crate - 0. Geocellular attenuation or soakaway crates are also extremely versatile, which means they can be configured around site constraints Stormwater attenuation and infiltration/soakaway crates ACO StormBrixx is a unique and patented plastic geocellular stormwater management system for attenuation and soakaway (infiltration) usage. Minimises risk of flooding and stores water (water to SUDS requirements) 400-litre capacity (2. This slowed rate of discharge helps to avoid downstream flooding and the erosion of water ways due. This one will surely meet your need thus relieving you from water logging issues. Come on site with us as we film a large attenuation tank installation for a new housing development - Lakeview Quarry in Somerset. Maximum installation depth of 5m. MWS158 Polystorm-R PSM1A Modular Water Storage Unit 1000x500x400mm (61T/m2 Loading) c/w PSMCLIP. 00 10,000 litre SuDS Rainwater Attenuation Tank with integrated flow regulator. 00 incl VAT. 00 incl VAT. uk. As the crate structure fills, water begins to exfiltrate from the tank into the surrounding ground. Attenuation is measured in decibels (dB) or voltage. ACO RoofBloxx is a complete roof attenuation system for blue, green and blue/green roofs. The honeycomb design is extremely strong allowing vehicle loading with minimal cover.