Sika SikaShield P24 S IN 3mm
A 3mm APP-modified, sand-surfaced torch-applied bituminous membrane on a non-woven polyester carrier, built for roofs, terraces, podiums and buried structures across Delhi NCR and Pan-India.
What is it?
A prefabricated 3mm APP-modified bituminous waterproofing sheet reinforced with a non-woven polyester carrier, sand-finished on top and fitted with a burn-off torch film beneath.
Where is it used?
Flat and sloping roofs, balconies and terraces under tiles or screed, podium decks, car park slabs, basements and other below-grade structures.
Why use it?
Delivers a fully bonded, monolithic membrane with high tensile and puncture resistance, and a sand face that keys the next layer of screed, tiles or a second membrane.
How is it applied?
Torch-fused to a primed, dry substrate roll by roll with 100mm side and 150mm end overlaps, welded until a bead of molten compound shows along each seam.
About Sika SikaShield P24 S IN 3mm
SikaShield P24 S IN 3mm is Sika’s sand-surfaced grade in the P24 torch-on membrane family, made for contractors who want a factory-controlled waterproofing layer rather than a site-mixed coating. The sheet is built around a non-woven polyester carrier that is saturated and coated with APP (atactic polypropylene) modified bitumen. The polyester core carries the load and resists tearing and puncture, while the APP compound gives the membrane its heat resistance and long-term stability. The top face is finished with fine sand, and the underside carries a thermofusible burn-off film that melts under the torch flame to signal that the bitumen has reached bonding temperature.
The “S” in the name marks the sand finish, which is what distinguishes this grade from the mineral-granule (MG) and film-faced (PE) versions of P24. That sand face is deliberate: it gives the next layer something to grip, so the membrane sits comfortably under a cement screed, tile bedding, protective concrete or a second cap sheet. At 3mm it is typically specified as the underlay or single-ply layer in exposed-then-protected assemblies. For Space Arc’s clients across Delhi NCR and Pan-India, it is a dependable choice on roofs, terraces, podiums and basement rafts where a torch-bonded system is preferred over liquid membranes.
The technical insight
The performance of this membrane comes from how the polyester and the APP bitumen work together. The non-woven polyester carrier is dimensionally stable and highly resistant to tearing, so it holds the sheet together while it is being unrolled hot and stretched over upstands and details; it is also rot-proof, which matters in buried and permanently damp conditions. The APP modification raises the softening point of the bitumen well above ambient roof temperatures, so the membrane resists flow and sagging on sun-exposed decks in Indian summers while staying flexible enough to remain crack-free at 0°C. Torch application is not just an adhesion method, it is the quality check: the burn-off film on the underside melts as the flame passes, and the fully melted film plus a visible 10mm bead of molten compound squeezing out of each overlap tells the applicator the bond is complete. Because the sheet is factory-made to a controlled thickness and reinforcement, the waterproofing barrier is uniform edge to edge, without the film-thickness variation you get with brush or roller-applied coatings.
Where it is used
- Waterproofing of flat and gently sloping RCC roofs under a protective screed, tile finish or ballast
- Balconies and terraces receiving tiles, gravel or a heavy protection layer
- Podium decks and landscaped areas over occupied space
- Car park decks and horizontal trafficked slabs with a suitable wearing course
- Basement rafts, retaining walls and other below-grade tanking against soil moisture
- Wet areas and plant rooms where a torch-bonded barrier is preferred
- Underlay or base membrane in a two-layer built-up system beneath a cap sheet
- Bridge decks, underpasses and civil structures requiring a durable buried membrane
Key advantages
- Factory-controlled 3mm thickness gives a uniform, reliable barrier across the whole area, unlike variable liquid coatings
- Non-woven polyester carrier delivers high tensile strength and strong resistance to tearing and puncture during and after laying
- Sand top finish keys the membrane to screed, tile bedding or a second layer without extra priming of the face
- APP modification provides a high softening point, so the sheet resists flow and sag on hot, sun-exposed decks
- Remains flexible and crack-free down to 0°C, accommodating thermal movement in the slab
- Fully bonded torch application leaves no water channels beneath the sheet, limiting the spread of any future puncture
- Burn-off film gives the applicator a clear visual cue that bonding temperature has been reached
- Rot-proof reinforcement suits permanently damp and buried conditions such as basements and podium fills
Limitations & considerations
- Requires open-flame torching by trained applicators and cannot be used where hot works are prohibited or a fire risk exists
- Needs a dry substrate below 6% moisture; it will not bond reliably to green concrete or a damp deck
- Application is restricted to +10°C to +40°C ambient and substrate, which can rule out very cold early mornings or peak-afternoon slab temperatures
- The sand-faced grade is intended to be protected or overlaid, not left permanently exposed to UV and traffic as a final wearing surface
- Overlaps and detailing at drains, upstands and penetrations demand skilled workmanship, or seams become the weak point
- Rolls must be stored upright, dry and unstacked, and are heavy to handle and position on site
Selection & best practice
Success with a torch-on membrane is decided on the substrate. The deck must be sound, cleaned of laitance and debris, free of sharp protrusions, and cured and dry with moisture below 6% before a compatible bituminous primer is applied and allowed to tack off. Work within the +10°C to +40°C window, unroll and re-roll each sheet so it can be torched from the centre outwards, and keep the flame moving so the burn-off film melts fully without scorching the bitumen. Lap sheets a minimum of 100mm on the sides and 150mm on the ends, staggering end laps, and weld each seam until a continuous 10mm bead of molten compound flows out along the line of the overlap. Give full attention to upstands, drains, pipe penetrations and internal corners with reinforcing pieces. Flood-test horizontal areas before covering, then place the screed, tiles or protection layer promptly so the sand-faced membrane is not left exposed to sun and foot traffic.
Specifications
| Membrane type | APP-modified bituminous, sand-surfaced, torch-applied |
| Reinforcement | Non-woven polyester carrier |
| Thickness | 3 mm (+0.3 / -0.2 mm) |
| Roll size | 1.0 m x 10.0 m |
| Tensile strength (longitudinal) | 650 ± 150 N/50 mm |
| Tensile strength (transversal) | 450 ± 150 N/50 mm |
| Elongation (both directions) | 40 ± 10 % |
| Cold flexibility | No cracking at 0 °C (EN 1109) |
| Application temperature | +10 °C to +40 °C ambient and substrate; substrate moisture < 6% |
| Overlaps | 100 mm sides, 150 mm ends |
| Storage | +5 °C to +35 °C, upright, dry; 12 months shelf life |
Industry use cases
Residential and commercial roofing
Base waterproofing on RCC roofs and terraces before a protective screed and tile finish, where a fully bonded torch-on layer is specified over liquid systems.
Basements and below-grade tanking
Rot-proof membrane on rafts and retaining walls to resist soil moisture and hydrostatic damp in deep basements and lift pits.
Podiums and landscaped decks
Waterproofing over occupied space beneath planter fills, paving and hardscape, with the sand face keying into the protective layer.
Infrastructure and car parks
Durable buried membrane for car park decks, bridge decks and underpasses that must carry a wearing course and traffic loads.
Two-layer built-up systems
Used as the underlay beneath a mineral or aluminium-faced cap sheet where a robust multi-layer bituminous system is required.
Frequently asked questions
What does the S in SikaShield P24 S mean, and how is it different from the MG grade?
Can this membrane be left exposed as the final surface?
What thickness and roll size does it come in?
What surface preparation and conditions are needed before torching?
How much overlap is required at the seams?
Is it suitable for basements and buried structures?
How we position Sika SikaShield P24 S IN 3mm
Within the Sika range, SikaShield P24 S IN 3mm is the sand-faced grade of the P24 torch-on family; specify the mineral-granule SikaShield P24 MG when the membrane will be left exposed, or step up to a 4mm grade for heavier-duty or trafficked decks. In a two-layer roof it pairs naturally as the underlay beneath a mineral or aluminium-faced Sika cap sheet, and it works alongside a Sika bituminous primer and Sika detailing accessories for upstands and penetrations. Where a project prefers a liquid-applied barrier instead of torch-on sheets, Space Arc can offer polyurethane or acrylic waterproofing systems from Sika or from our Dr. Fixit and Fosroc ranges. As authorised distributor and applicator for multiple brands, we help engineers and consultants match the membrane to the deck, the protection layer and the site’s fire-works constraints rather than defaulting to a single product.
Related Waterproofing products
Source Sika SikaShield P24 S IN 3mm for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.