Protecto-Drain G8

Protecto-Drain G8 2017-12-20T02:22:34+00:00
Protecto-drain g8 is used for subterranean applications and foundation walls where a greater degree of drainage and protection is required on the vertical plane.

It creates an air gap between the structure and the earthworks, ensuring complete protection to the waterproofing membrane on the structural wall after backfill.


Protecto-drain G8 is made from the same HDPE (high density polyethylene) material, but has a geotextile fabric bonded to one side. It is designed to protect vertical surfaces from damage with the laminated non-woven geotextile layer separating the soil from the membrane, giving greater protection to the subterranean waterproofed surface. It is also lightweight and simple to install.



c3Protecto-drain G8 is installed with the geotextile fabric facing towards the soil backfill. Water will pass through the geotextile but the HDPE cupped membrane prevents further ingress. The water will fall down the face of the HDPE membrane with the force of gravity. The specially designed profile and the high compression strength of the cupped HDPE means that a constant air gap is maintained, preventing clogging of the drainage channel.

The HDPE is very lightweight and easy to handle. This makes it ideal for fixing to the vertical plane.

See a clip of installation by clicking here.



The area immediately behind the Protecto-drain G8 should be filled with free-draining material such as shingle to improve drainage. Since effective drainage occurs but the soil remains in place, the earth will not become eroded or saturated near the drainage areas. Therefore, common problems such as subsidence, waterlogging and rising damp are avoided.


The geotextile filters out particles but allows the water to run through the fabric and horizontally down through the 8mm air gap. At the bottom of the surface an effective drain should be constructed – the water needs a place to escape.

Click here for a clip on how to install a French Drain.



A perforated pipe (French drain) should be installed at the bottom of the vertical surface on a gradient, and Protecto-drain G8 wrapped around it so that the HDPE membrane is on the underside and the filter fleece is across the top. The channel should be covered with free draining gravel.


Protecto-drain G8 is ideal for lining planters and vegetated areas.


The membrane is easily shaped around corners and details such as drainpipes and outlets without risk or breaking. These are the areas where clogging is most likely to occur, so applicators can lift the geotextile backing away easily from the membrane in order to wrap around outlet pipes, thus maintaining complete separation and preventing clogging.


The area can then be backfilled with soil and planted up. The vegetation will not become waterlogged and any excess water can be directed and channelled properly into the drainage system, for recycling if required.



Effective drainage of block paving can also be achieved with Protecto-drain G8. The membrane is laid onto the podium deck above the waterproofing and beneath the block paving with the geotextile on the upper side, in exactly the same way as tanking. The blocks are either suspended on Wallbarn support pads and laid onto Protecto-drain G8….


….or laid directly onto the membrane, butted together, and the gaps filled with fine sand. Please click here for a video clip . The cavity between the geotextile and the HDPE means that rainwater can escape downwards faster and none of the sand will be lost to erosion. Therefore more stable, puddle-free block paving is created.

When installing onto a vertical surface, Protecto-drain G8 can be fixed with double sided bitumen tape. Click here for a video clip showing how the membrane is fixed to the wall.



Or by using nails and plugs with a cover profile secured at the top….


….while on a horizontal plane the membrane can be secured together with bitumen tape, ensuring a 20cm overlap.

Technical Data
Technical features Technical data Test Method
Membrane material High density polyethylene (HDPE)  
Filter material Polypropylene geotextile (100gsm)  
Roll width 2 metres calibrated measuring tape
Roll length 15 or 20 metres calibrated measuring tape
Roll weight 650 gsm (±10%) calibrated thickness
measuring tape
Rolls per pallet 6  
Height of cups 8mm MDV
Number of cups 1500 pieces per m2 MDV
Resistance to water penetration W1 EN 1928
Compression strength 250kN / m2 MDV
Tensile strength MD = 330 N / 50mm EN 12311-2
Tensile strength CMD = 335 N / 50mm EN 12311-2
Elongation MD = 28.7 N EN 12311-2
Elongation CMD = 26.2 N EN 12311-2
Resistance to tearing MD = 332 N EN 12310-1
Resistance to tearing CMD = 349 N EN 12310-1
Resistance to static loading No perforation at 200 N in 24 hrs EN 12730
Durability waterproof / passed EN 1296 & EN 13984
Exposure to liquid chemicals waterproof EN 1847
Air volume between the cups 5.5 litres per m2 MDV
Water drainage capacity 4.6 litres per m2 MDV
Temperature tolerance – 30°C to + 80°C MDV
Reaction to fire B2 (B1 available by special request) DIN 4102
Physical characteristics Rot-proof, resistant to fungus and bacteria. Will not leach chemicals. Not harmful to drinking water. No health hazards under normal use


Used as a mechanical protection against soil and root movement along foundation walls. It can be installed with a 20cm overlap and fixed with nails and sealing buttons 5 cm from the top edges of the roll and 20cm from each roll. Edging profile is installed to prevent soil ingress into the cavity. Maximum build-up 8 metres high.

Laid horizontally and fixed using sealing tape in the overlapping areas the sheets protect concrete flooring form rising damp and keep reinforcement mesh in place firmly during the concrete works.

Protect against prolonged exposure to direct sunlight and temperatures over 25 °C

When used in the correct manner and application, the material will be rot proof for 20 years. Wallbarn application rules and proper site storage, handling and installation practices must be carried out as a prerequisite for any possible future warranty claims.

No known dangerous substances

This datasheet represents the current knowledge of the product, but may be revised by Wallbarn in the future. It is the duty of the customer and installer to be clear that this product is suitable for the purposes it is used for.

This technical datasheet may be revised or changed at any time without prior notice. It is the duty of the customer and installer to be sure they possess the latest version of the datasheet.

To download our current brochure (in Adobe Acrobat PDF format) please click here.

Wallbarn Protecto-drain is high density polyethylene (HDPE) cupped drainage sheeting which acts as a protection and drainage layer for waterproofed surfaces.