STP ShaliDrain 08
An 8 mm dimpled HDPE drainage and protection board that shields your waterproofing membrane and channels ground water away from the structure.
What is it?
A one-side dimpled (cuspated) high-density polyethylene board with 8 mm studs from STP Limited, used as a combined drainage layer and mechanical protection over waterproofing membranes.
Where is it used?
Basement and retaining walls, raft edges, podium decks, terrace and roof gardens, and tunnels — anywhere a membrane needs protection during backfill plus a route for percolating water.
Why use it?
It keeps hydrostatic pressure off the waterproofing, protects the membrane from backfill and sharp fill, and lets seepage drain freely to the perimeter drain instead of ponding against the structure.
How is it applied?
Fixed dimples-toward-the-wall over the cured membrane with washer fixings or tape, joints overlapped, then backfilled or screeded over — no adhesives or hot works needed.
About STP ShaliDrain 08
STP ShaliDrain 08 is a drainage and protection board pressed from high-density polyethylene into a one-side dimpled, or cuspated, profile with studs 8 mm deep. On a below-grade or buried structure the waterproofing membrane does the sealing, but it is vulnerable on two fronts: the backfill and fill material that get compacted against it during construction, and the standing water that builds up against the wall once the ground is saturated. ShaliDrain 08 answers both. The dimpled sheet sits between the membrane and the earth, taking the abrasion and point loads of the backfill, while the void created by the studs gives percolating water a continuous channel to run down to the perimeter drain rather than pressing against the slab.\n\nSpace Arc Engineering supplies ShaliDrain 08 as an authorised project distributor for STP Limited, serving Delhi NCR and Pan-India. The board is light, flexible and resilient, which makes it quick to handle and fix on site even on tall retaining walls and irregular podium profiles. It is the plain-board grade in the ShaliDrain family — the void and protection without a bonded filter fabric — so it is the right pick where the fill is clean or where a separate geotextile is being laid, and where cost per square metre matters across a large backfilled area. Where a filter layer must be integral to the board, the geotextile-faced grades take over.
The technical insight
The board works on a simple hydraulic principle: relieve the pressure and the membrane lasts. Compacted soil against a waterproofed wall holds water like a sponge, and a saturated backfill exerts full hydrostatic head on the structure. By interposing an 8 mm dimpled void, ShaliDrain 08 breaks that continuous water column — seepage that reaches the board drains down the interconnected channels between the studs under gravity and exits at the footing drain, so the head that can build against the membrane is limited to the small volume the void holds at any moment. The studs also do structural duty: they stand the earth off the membrane so that stones, formwork debris and compaction loads bear on the tough HDPE ribs instead of puncturing or abrading the waterproofing. Because HDPE is chemically inert and rot-proof, the board keeps performing in wet, alkaline soil for the design life of the structure, and its flexibility lets it follow curved walls and step over construction joints without cracking.
Where it is used
- Protection and drainage over membranes on basement and retaining walls before backfilling
- Raft and foundation slab-edge protection against fill damage
- Podium decks and sunken slabs where a drainage void is needed above the waterproofing
- Terrace gardens and roof gardens as the sub-soil drainage layer beneath planting media
- Landscaped and green-roof build-ups to move irrigation and rain runoff to outlets
- Tunnels and cut-and-cover structures for lining protection and seepage control
- Planter boxes and tree pits to prevent waterlogging of the root zone
- Blindside and shored-wall situations where the membrane must survive backfill
Key advantages
- Protects the waterproofing membrane from puncture and abrasion during backfilling and compaction
- Creates a free-draining 8 mm void that relieves hydrostatic pressure on the structure
- HDPE is non-toxic, rot-proof and chemically resistant to alkaline and acidic soils
- Light in weight, so a single worker can position and fix large sheets quickly
- Flexible and resilient — follows curved and stepped walls without cracking
- Cold-applied with fixings or tape; no adhesives, primers or hot works on site
- Speeds up the backfill programme by combining protection and drainage in one layer
- Compatible with the common membrane systems used below grade
Limitations & considerations
- The plain 08 grade has no bonded geotextile, so fine soils can migrate into the void unless a separate filter fabric is laid over it
- It is a drainage and protection layer, not a waterproofing membrane — it must always be used over a proper membrane, never on its own
- Dimple studs must face the wall/membrane; installing the board the wrong way round defeats the drainage void
- Long exposure to UV before backfilling can degrade HDPE, so it should be covered promptly
- The 8 mm void suits typical below-grade heads; very deep or heavily loaded structures may call for a taller-stud grade
- Poorly overlapped joints or crushed studs from over-compaction can locally block drainage
Selection & best practice
Install ShaliDrain 08 only after the waterproofing membrane has been applied, cured and, where required, tested. Fix the board with the dimples facing the membrane so the flat face meets the backfill and the studs form the drainage void against the wall. On vertical faces, hang the sheet from the top and secure it with washer-head fixings or approved tape into the substrate, keeping penetrations to a minimum. Lap adjacent sheets by at least one row of dimples and seal the laps so backfill cannot enter the void. Where the surrounding fill is fine or silty, lay a non-woven geotextile filter over the flat face — or specify the geotextile-bonded ShaliDrain 8F grade instead — to keep the void clear. Carry the board down to a working perimeter or footing drain so collected water has somewhere to go, and dress it neatly around pipe and service penetrations. Backfill in even lifts and compact moderately; avoid dropping large stones or ramming heavy plant directly against the studs. Keep the sheet covered from prolonged sunlight before backfilling.
Specifications
| Product type | One-side dimpled (cuspated) drainage and protection board |
| Material | High-Density Polyethylene (HDPE) |
| Dimple / stud height | 8 mm |
| Geotextile | None — plain board (geotextile-faced option is ShaliDrain 8F, 110 GSM PP) |
| Characteristics | Light weight, flexible, strong, resilient, non-toxic, rot-proof |
| Function | Membrane protection plus free-draining void for hydrostatic pressure relief |
| Application method | Cold-fixed with washer fixings / tape; no adhesive or hot works |
Industry use cases
Commercial basements
Protects the applied membrane on deep basement and retaining walls and drains ground water to the raft-edge drain before backfilling.
Landscape & roof gardens
Forms the sub-soil drainage layer beneath planting media on terraces and podiums so root zones don’t waterlog.
Infrastructure & tunnels
Shields tunnel and cut-and-cover linings from fill damage and manages seepage behind the structure.
Residential podiums & planters
Provides a drainage void over sunken slabs, planter boxes and tree pits in gated developments and villas.
Water-retaining & buried tanks
Gives externally waterproofed tanks and sumps a protected, free-draining surround during backfill.
Frequently asked questions
Is ShaliDrain 08 a waterproofing product on its own?
What does the ’08’ mean, and how is it different from 8F, 10 or 12F?
Which way round does the board go?
Do I need a separate geotextile with the plain 08 board?
How is it fixed and does it need adhesive?
Can Space Arc supply it across India with technical support?
How we position STP ShaliDrain 08
ShaliDrain 08 is the plain, cost-effective drainage board in STP’s ShaliDrain range. Where the fill is fine and an integral filter is wanted, step up to ShaliDrain 8F, which adds a 110 GSM polypropylene geotextile at the same 8 mm void; for deeper structures or higher flows, ShaliDrain 10, 10F or 12F give taller 10 mm and 12 mm voids, and ShaliDrainCell 30 handles heavy sub-soil drainage under roof gardens. It sits above the STP waterproofing membrane you choose — pair it with the appropriate ShaliSeal or Shalitex system so the membrane and its protection come from one family. Across our other brands, it complements Fosroc, Dr. Fixit and Sika below-grade membranes equally well as a protection-and-drainage layer.
Fosroc Proofex Sheetdrain — Specify the Fosroc geocomposite when the project calls for an 8 mm HDPE cuspated core with a bonded filter geotextile in a single sheet and a Fosroc-approved system warranty.
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Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.