Rainsmart Heavy 65T 20 Cubic Metre Shallow Flat Pack

This soakaway set automatically qualifies for 10% off through our spend and save discounts!

Our 20 cubic metre 65-tonne heavy shallow soakaway system coming flat-packed.

You will need 156 shallow crates which we would recommend laying 13 crates wide by 12 crates long. This will give you a complete soakaway of 7.8m (W) x 7.2m (L) x 0.36m (D).

A rubber mallet for assembly and a number of cable ties will also be included to join the crates together and to clamp the membrane around your pipe entry points.

Assembly of this set really is a quick and easy process - full instructions can be viewed in our installation sheet.

Size, load and capacity

The dimensions of the complete soakaway are 7.8m (W) x 7.2m (L) x 0.36m (D)

Rainsmart soakaway crates have a void ratio of 95% - this is the amount of free space within the crate structure that can be used for rainwater storage. The capacity of this 20 cubic metre soakaway is an impressive 19,188 Litres.

The vertical crush load capacity of 65 tonnes per square metre ensures that the Rainsmart 65 tonne heavy can be used in commercial scenarios.

Joining crates together

Clips are not required to hold the crates together. No clips on any crate system are structural it is always the side fill on any soakaway installation which adds the stability needed to hold the structure in place. Cable Ties are included with our 20m Soakaway Sets and these are used to connect two sides of the complete soakaway together in an L formation (the other crates are then jammed into this corner). These ties are used purely to hold the crates in place until the sand or gravel side fill has been added.

Geotextile & Damp Proof Membranes

We stock a number of membranes that will be needed for your installation - depending on the design. A non-woven geo-textile membrane will be needed in order to ensure that no silt or soil particles enter the crate. If you don't want infiltration to occur from the soakaway you will also need to install an outer layer of damp proof membrane - this will prevent water from leaving the soakaway.

Our membranes come in 4.5-metre widths and can be purchased by the metre or in 100m rolls. For this soakaway, we would recommend that you buy a roll, in order to ensure you have enough coverage, but as a guide, you will need approx. 30 metres of the 4.5-metre roll.

Inspection & Cleaning

For best practice, we always recommend that a pre-filter such as our Sentinel Silt Trap is used in conjunction with any modular soakaway system. Emptying the filter on a regular basis (this is only a five-minute job) will maintain the efficiency of the soakaway and greatly increase its lifespan.

All outward-facing crate surfaces of any soakaway should be wrapped in a non-woven geotextile membrane, which allows the free passage of water but prevents any soil or sand particles from entering the soakaway, maintaining its long term efficiency.

Flow Control with Attenuation

With the increase in emphasis on SuDS local planning authorities and specifiers are implementing flow control systems to prevent flooding. Through attenuation rainwater is released back into the network, but in order to ensure you aren't passing any potential issues downstream this is done so at a controlled speed. Check out our Flow Controls page for more information about Orifice Chambers & Valves.

Connecting Pipes to Soakaways

The 110mm (or 160mm) drainage pipe is fed into the soakaway via the entry plate. Geotextile membrane should be installed over the opening first and then a small cross should be cut in the membrane at the entry point with a sharp knife. Carefully peel back the membrane, insert the pipe and tape or clamp the membrane tightly around the outside of the pipe to stop the ingress of any soil particles.

For a closer look at Soakaway Crates in general please take a look at our introductory video.