Geocellular Solutions For Shallower Depths
Our latest geocellular system extends the choice and flexibility of the Polypipe range by providing robust, effective source control through attenuation or soakaway at shallower levels.
Permavoid Modular Cell 95% void ratio
Traditional Aggregate 30% void ratio
Why a shallower application?
Shallower attenuation or soakaway structures are often necessary because the ground at greater depths presents a construction challenge of one kind or another. This could be the presence of chemicals or contamination left over from previous land use, underground watercourses or an unusually.
Shallower attenuation or soakaway structures are often necessary because the ground at greater depths presents a construction challenge of one kind or another. This could be the presence of chemicals or contamination left over from previous land use, underground watercourses or an unusually.
Some drainage engineers prefer a shallower approach because it does not rely on expensive pumping equipment. Shallower methods also have a reduced environmental impact because they require less excavation and fewer trips to transport infill and rubble to and from the site.
Shallow and deep working together
We are the only manufacturer who can offer both shallow and deep solutions. By talking to us at the early stages of your project you may find that a combination of both shallow and deep systems installed in different areas across the site may provide cost savings to your projects.
Where can Permavoid help
With high water tables High water tables and even perched water at shallow depth require specific design and construction measures to avoid issues such as flotation of attenuation structures and often prevents the use of soakaways. Anti-flotation and temporary dewatering measures are invariably very expensive, but Permavoid can often provide the attenuation or infiltration solution by avoiding groundwater issues.
In contaminated sites Redevelopment of brownfield sites is common-place and issues of ground contamination often come hand in hand. The use of Permavoid shallow attenuation or soakaway structures can very often avoid the need to excavate into contaminated soils that invariably incur significant abnormal costs in either on-site remediation or off-site disposal and the numerous associated environmental issues. Thus, the use of Permavoid systems can often avoid substantial costs and reduce overall construction time.
On podium decking On podium decks, key design, construction and cost issues usually involve issues of weight of overlying construction, creation of falls for drainage layers, pipe penetrations through the deck and loss of headroom within the underlying basement due to the need to suspend drainage beneath the overlying deck. Permavoid systems can avoid all of these issues as it can provide an effective drainage and attenuation layer without the need of falls or outlet penetrations through the deck; is lightweight and can accommodate a wide range of finishes including soft
Avoidance of pumping stations Shallow Permavoid systems can very often avoid the need for pumping that might otherwise be required with conventional drainage or deep attention tank solutions. Pumped solutions can be costly to install and maintain and considered to be environmentally unsustainable.
Over hard rock Excavation of hard rock is usually expensive and slow. However, Permavoid is ideal for use on sites that are underlain by hard rock at shallow depth, as the systems can be incorporated into the pavement construction invariably avoiding any net additional excavation for the drainage system.
Difficult site access In narrow, restricted or otherwise limited access sites, Permavoid can be easily manhandled into place without any heavy lifting or off-loading gear. With a 95% void ratio space for maximum water retention, the lightweight cells can be carried and installed by a single construction worker.
Product information
- Designed and tested for attenuation or soakaway at shallower depths
- Provides effective source control
- Interlocking raft for rigidity and a high compressive and tensile strength under load
- Can be installed above a high water table
- Allows water to be spread across a wide area
- Suitable for use beneath porous and non-porous surfaces
- Ideal for brownfield or contaminated sites
- Removes the requirement for pumping stations
- Reduction in excavation depth and cost
- No need for trench supports or plant to deliver and remove trench support panels
- Provides treatment to remove silt and hydrocarbon deposits
- Oil interception at source â no need for petrol interceptors
- Can be used in combination with the full range of Polystorm Geocellular solutions for deeper applications