Protection & Drainage
Drainage
We offer a variety of drainage products including boards sheeting and channels.
See our full range below.
Benefits of our drainage boards:
- Rot-proof
- Will not pollute the water run-off
- High compression strength
- Dimpled (“egg box”) cup profile available in different sizes, ensuring a constant air gap between the layers of concrete
- Lightweight, easy to transport and install

Protecto-drain 8
Flexible protection and drainage layer
- Made from high density polyethylene (HDPE)
- Lightweight, flexible and durable
- Protects waterproofing membranes from abrasion or puncture
- Dimpled “egg-box” profile giving high compression strength
- High tearing and impact resistant
- Rot-proof, safe for drinking water
- Supplied in rolls of 2x 20m
Suitable for subterranean foundation walls, tanking and basement construction.
The 8mm deep cups provide an air gap between the concrete structure and the backfill. Water runs down the outer surface towards a drain at the bottom of the structure.
Creates a permanent air gap when fixed to surface walls and floors, preventing hydrostatic pressure and helping to ventilate the structural wall.
Fixing
- Nails pass through the membrane and don’t split the material
- Plugs seal the cups
- A cover profile fitted at the top prevents particles dropping behind the membrane
- Sheets can be bonded to the structural wall using bitumen based adhesive tape or fixed with nails and plugs
- Each sheet must overlap each other by at least 20cm for secure installation
Bonding sheets
- Can be bonded together to create one seamless watertight layer
- Can be fitted to floors to act as a vapour barrier and a damp proof layer
Storage & Handling
Protect against prolonged exposure to direct sunlight and temperatures over 25°C

Protecto-drain 20
Heavy Duty dimpled drainage sheeting for use in foundation walls, tunnels, bridges and civil engineering projects.
- Made from strong, flexible HDPE
- High compression strength with a dimpled (“egg box”) 20mm cup profile
- Cupped profile ensures a constant air gap between the layers of concrete
- Copes with larger quantities of ground water and drainage easily
- Used in both vertical and horizontal planes
- Does not pollute the water run off
- Rebar can be laid directly onto the membrane without damage and concrete can be poured directly onto it.
- Multiple sheets can be clipped into place by overlapping the cups and sealing joints with adhesive tape
Uses
- Heavier groundworks including tunnel lining and road construction
- Waterproofing and protection layer between layers of concrete
- To seal building envelopes on new build including foundations
- To manage and control subterranean water by channeling to effective drainage
By sticking to simple principles of not stopping water but redirecting it, hydrostatic pressure points are prevented.
Fixing
- Sheets are bonded together by overlapping cups and sealing with tape
- Can be taped with double sided tape or mechanically fixed with nails and special waterproofing plugs
Storage & Handling
Protect against prolonged exposure to direct sunlight and temperatures over 25 °C

Protecto-drain 20P
Heavy duty HDPE dimpled drainage board with drainage holes – suitable for green roofing
- Suitable for extensive green roof systems including sedum roofs, wildflower and biodiverse roofs, grasses and dwarf plants, with substrates up to a depth of 200mm
- For use on structural decks which have been fully waterproofed, protected and are capable to holding the weight of a saturated green roof
- Lightweight, tough yet flexible and can be shaped around objects
- Holds water within its profile to nourish vegetation above the filtration layer (5 litres per m2)
- Does not pollute the water run off
Application
- Laid horizontally onto geotextile filtration fabric beneath, with cups facing up
- Membrane overlapped and covered with loose laid geotextile filtration layer above, separating substrate from HDPE membrane
- Growing medium / substrate is laid on top
- Provides air gap to allow free-drainage of water
- Slows run-off of water but prevents waterlogging
- Water held in reservoir cups can be drawn up back into the substrate in dry periods
- Excess water dissipates through the perforations between each cup and through the drainage channel out into the outlet
Handling
- Supplied in rolls 2 x 20m
- Easy to transport and install
- Multiple sheets can be clipped into place by overlapping the cups and sealing joints with adhesive tape
Part of a comprehensive drainage system for roll-out extensive green roof systems. Designers need to be sure that the storage capacity and drainage flow rate is sufficient for the green roof type being constructed.
It is important to remember, however, that these materials do not alone provide a drought resistant system. Irrigation in dry or hot weather and regular maintenance is required for all roof gardens and green roofs.
Storage
Protect against prolonged exposure to direct sunlight and temperatures over 25 °C
Please see our green roof pages here Green Roof Systems for more details.

Protecto-drain G8
Flexible protection and drainage layer with geotextile bonded one side
- Made from high density polyethylene (“HDPE”)
- Geotextile fabric bonded to one side
- High compression strength with a dimpled (“egg box”) profile
- Protects vertical surfaces from damage whilst allowing free drainage of groundwater
- Used on the vertical plane for foundation walls
- Used as lining for planters
- Used on the horizontal plane for effective drainage of block paving
- Geotextile layer separates soil from the membrane whilst giving protection to the membrane
- Creates an air gap between the structure and the earthworks
- Lightweight and simple to use, easy to fix
For Foundation Walls
HDPE dimpled membrane with bonded geotextile fabric allows water to pass through the fabric but keeps soil particles in place. Water will drain downwards along the surface of the HDPE membrane towards the drain beneath.
- Protecto-drain G8 is installed with the geotextile fabric facing towards the soil backfill/shingle
- Water passes through geotextile and down through the 8mm air gap around the dimpled cups
- 100gsm geotextile membrane ensures consistent flow rate of water, prevents deluge
- Constant air gap is maintained, ensuring free flow and preventing clogging of the drainage channel beneath
- An effective drain – such as a French Drain – should be constructed at the bottom of the surface to allow water dissipation
- Prevents waterlogging, subsidence and rising damp
- Individual sheets can be fixed with double sided bitumen tape when installing on a vertical plane to ensure a seamless, water tight membrane
For Planters
- Ideal for lining planters and vegetated areas
- Installed with the geotextile fabric facing towards the soil
- Membrane is easily shaped around corners and details such as downpipes and outlets
- Can be cut and bonded easily to create seal around inside wall of planter
- Excess water passes through geotextile fabric to 8mm air gap and is channelled away
- Prevents clogging of the drainage outlet
For Use on the Horizontal Plane
- Used for effective drainage of block paving
- Good flood management on pedestrian areas
- Membrane is laid between the waterproofing and the block paving with the geotextile membrane facing upwards
- Paving slabs can be suspended on Wallbarn pedestals
- or Blocks can be laid directly onto the membrane and gaps filled with fine sand
- Water passes through geotextile fabric onto HDPE membrane below and along the top of the membrane towards the drain
- Sand filling on block paving is held in place on the geotextile and not washed away
- Prevents clogging of the drainage system and allows puddle free paving
Fixing – Vertical Plane
When installing onto a vertical surface, Protecto-drain G8 can be fixed with double sided bitumen tape . Always ensure each sheet is overlapped by at least 20cm to ensure a watertight seal.
Fixing – Horizontal Plane
Lay membrane down with geotextile side facing up and overlay with sand / backfill. Seal each sheet securely with double sided Protecto-tape, ensuring a 20cm overlap, to ensure a watertight seal.
> See how the membrane is fixed to the wall
Storage & Handling
Protect against prolonged exposure to direct sunlight and temperatures over 25 °C

Drainage Channel
- Includes anti-slip galvanized steel grate
- Channels surface water to outlets
- Quick and easy installation
- 1m sections simply join together to create seamless channel
- Spring-loaded clips lock/release grate for easy maintenance
- Suitable for pedestrian and lightly trafficked areas
- CE marked and fully certified to Load Class A15 BS EN 1433
- Eco-friendly and 100% recyclable
- Accessory pack available for drainpipe connection (see below)
Applications:
- Domestic applications: driveways, gardens & patios
- Public areas: pedestrian walkways, recreational areas, schools, parks and playing fields
Dimensions
- Outer dimensions: 120mm high x 135mm wide
- Inner dimensions: 90mm high x 100mm wide
Material
- Channel: High Density Polyethylene (HDPE)
- Grate: galvanised steel
Connect individual channels together using tongue and groove section at each end to create longer drainage trenches
Locking clips
The locking clips make Wallbarn’s Protecto-drain Drainage Channel ideal for easy access and cleaning. The clips keep the steel grate securely in place but allow for easy access to the gutter section.
- There are two points in the steel grate where a pointed implement can be pressed down to release the spring-loaded side locking clips
- The steel grate can be lifted away from the channel easily
- No screws or fixings are involved
Accessories
- 2 x side bars to close the channel
- 1 x Ø110mm circular connecting bracket for underside of channel to link channel to drainpipe

Pro-drain 20G
Coming soon…

Pro-drain 40P
Coming soon…

Pro-drain 60P
Coming soon…
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.
Protecto-Drain 8 Technical Data
Technical features | Technical data | Test Method |
---|---|---|
Material | High density polyethylene (HDPE) | |
Roll width | 2 metres | calibrated measuring tape |
Roll length | 20 metres | calibrated measuring tape |
Roll weight | 550 gsm (±10%) | calibrated thickness |
measuring tape | ||
Rolls per pallet | 12 | |
Compression strength | 250 kN per m2 | MDV |
Height of cups | 8mm | MDV |
Number of cups | 1500 pieces per m2 | MDV |
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 |
Protecto-Drain G8 Technical Data
Technical features | Technical data | Test Method |
---|---|---|
Membrane material | High density polyethylene (HDPE) | |
Filter material | Polypropylene geotextile (100gsm) | |
Roll width | 1 metre or 2 metres | calibrated measuring tape |
Roll length | 15 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 |
Protecto-Drain 20 Technical Data
Technical features | Technical data | Test Method |
---|---|---|
Material | High density polyethylene (HDPE) | |
Roll width | 2 metres | calibrated measuring tape |
Roll length | 20 metres | calibrated measuring tape |
Roll weight | 1,000 gsm (±10%) | calibrated thicknessmeasuring tape |
Rolls per pallet | 5 | |
Compression strength | 180 kN per m2 | MDV |
Height of cups | 20mm | MDV |
Air volume between the cups | 14 litres per m2 | MDV |
Water drainage capacity | 10 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 |
Protecto-Drain 20P Technical Data
Technical features | Technical data | Test Method |
---|---|---|
Material | High-density polyethylene (HDPE) | |
Roll width | 2 metres | calibrated measuring tape |
Roll length | 20 metres | calibrated measuring tape |
Roll weight | 550 gsm (±10%) | calibrated thickness-measuring tape |
Rolls per pallet | 5 | |
Compression strength | 180 kN per m2 | MDV |
Height of cups | 20mm | MDV |
Air volume between the cups | 14 litres per m2 | MDV |
Water drainage capacity | 10 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 | |
APPLICATION |
A15 Drainage Channel Technical Data
General properties | Technical Data | Test Method |
---|---|---|
Width of channel (inside/outside) | 100mm / 135mm | Manufacturer’s declared value |
Height of channel (inside/outside) | 90mm / 120mm | Manufacturer’s declared value |
Free cross-section of the channel | 100 x 90 mm | Manufacturer’s declared value |
Length of channel | 1000 mm | Manufacturer’s declared value |
Unit weight of channel | 1,250 kg | Manufacturer’s declared value |
Width of grid | 124 mm | Manufacturer’s declared value |
Height of grid | 20 mm | Manufacturer’s declared value |
Unit weight of grid | 1.3 kg | Manufacturer’s declared value |
Cross section of the outlet | ø110 mm | Manufacturer’s declared value |
Load class | A 15 (15kN = 1500kg test load) | EN 1433 |
Storage: | On pallets under dry conditions, protected against atmospheric exposure and heat sources. |
---|---|
Health & Safety: | No labelling required in accordance with the relevant regulation (EC) No. 1907/2006 of the European Parliament and of the Council (REACH). |
Specification: | EN 1433 |
Guarantee: | In accordance with the current legislation and the conditions of the distributor. The observation of the applicable rules of the product and presentation of the invoice constitutes a prerequisite for possible future warranty claims. |
NBS Source
- Protecto Drain 20
- Protecto Drain 20P
- Protecto Drain 8
- Protecto Drain 8 Lightweight
- Protecto-Drain – A15 Class Drainage Channel
- Protecto Drain G8