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ROOFEXSEAL PU 212
- Expansion joint leakage
- Sealing concrete floor joints
- Facade and cladding joints
- Door and window perimeter gaps
ROOFEXSEAL PU is a low-modulus, single-component, high-performance polyurethane sealant. Once cured, it forms a tough, flexible seal capable of cyclic expansion and compression movement of 50% (±25%) of the original joint width. Virtually unaffected by rain, sunlight, snow, sleet, UV radiation, ozone, and atmospheric pollution, it retains its original properties for years of exposure.
Specifications
Figures are controlled laboratory results. Actual site performance varies with substrate, temperature, humidity, application method and workmanship — please confirm the current product datasheet before specification.
Where to use ROOFEXSEAL PU 212: polyurethane joint sealant for moving joints
ROOFEXSEAL PU 212 is a polyurethane joint sealant, single-component and low-modulus, that cures with moisture to a tough, flexible seal. It is gunned from a cartridge or sausage into the joint in one continuous run. As a PU sealant for expansion joints it takes cyclic movement of ±25% of the original joint width.
Floor Joints
Gun grade or pour grade sealant with Shore A hardness of 50.
Granite, Sandstone & Marble Pointing
Supplied in White and Grey for pointing stone joints.
Roads, Runways, Aprons & Pavement Joints
Temperature resistance from -30°C to +70°C once cured.
Precast & Block Work
Primerless adhesion to concrete, masonry and bricks.
Façade & Cladding Panels
Virtually unaffected by rain, sunlight, UV radiation and ozone.
Construction & Expansion Joints
Takes ±25% cyclic movement with elongation at break above 600%.
Door & Window Perimeter Sealing
Bonds to timber, aluminium and metal without a primer.
Potable Water Tanks
Listed for potable water tanks, with AS 4020:2018 among its standards.
For expansion joint leakage, the key figures are ±25% joint movement, elongation at break above 600% and tensile strength of 2.5–3.0 N/mm². It is tack-free in 50 minutes, cures at 3.5 mm per 24 hours and reaches full cure in 7 days. Standards listed include ASTM C920-87 and BS 5212. A 600 ml sausage covers about 20 lineal metres of a 5 mm × 6 mm joint. This floor joint sealant has a shelf life of 6 months. Apply at 5°C to 35°C in one continuous pass with positive pressure.
Armstrong Chemicals supplies ROOFEXSEAL PU 212 to sites across Telangana, Andhra Pradesh, Karnataka, Kerala and Tamil Nadu, including Hyderabad, Vijayawada, Bengaluru, Kochi and Chennai.
Built for Joints That Actually Move
A low-modulus polyurethane sealant rated for ±25% cyclic joint movement and over 600% elongation, with primerless adhesion to almost every building substrate — from floor joints to potable water tanks.
Get a QuoteWhy Rigid Sealants Fail at the Joint
High-modulus or poorly rated sealants can't absorb real expansion-joint movement — they split, debond, or let water through at exactly the point they're meant to protect.
The ROOFEXSEAL PU Advantage
A low-modulus sealant rated for ±25% cyclic joint movement (ASTM C719), with primerless adhesion to almost any building substrate.
Built for Real Movement
Low-modulus design absorbs ±25% cyclic expansion and compression (ASTM C719) with over 600% elongation at break — engineered for joints that move, not just gaps that need filling.
No Primer, No Problem
Excellent primerless adhesion to concrete, timber, masonry, bricks, aluminium, metal and ceramics — one sealant across nearly every substrate on site.
Trusted on India's Toughest Infrastructure
Choose Your Application Method
Cartridge Application
Standard 600ml cartridge loaded into an extrusion gun.
Built to Move, Built to Last
A sealant built for joints that flex, expand and contract — not just gaps that need filling.
Engineered for Joint Movement
Low modulus, ±25% rated to ASTM C719, with over 600% elongation at break — built to flex with real expansion and contraction.
Primerless, Multi-Substrate Bond
High bond strength directly to concrete, timber, masonry, bricks, aluminium, metal and ceramics, with no primer required.
Resists Chemicals & Fungal Attack
Resists hydrolysis, ageing, and chemicals used in service stations, dilute acids and alkalies; fungal resistance rated to AS 1157.2.
Built for India's Infrastructure
Tested, approved and used across CPWD, State PWDs, Irrigation, Housing Boards, Power Projects, Steel Projects, Road Projects, MES and Railways.
Applicable Areas
Packing & Shelf Life
Supplied in 600ml packs. Shelf life of 6 months from manufacture date — notably shorter than Armstrong's coating products; check stock rotation accordingly.
Surface Preparation
Remove all foreign matter, dust, loose particles, oil, grease, frost, water, dirt, old sealants and protective coatings. Clean non-porous or plastic surfaces with solvent or mechanical means — wipe solvent dry with a clean cloth before it air-evaporates.
Primerless Adhesion
Bonds directly, with no primer required, to concrete, timber, masonry, bricks, aluminium, metal and ceramics.
Joint Coverage
Coverage depends on joint width and depth. A custom joint-dimension calculator (width × depth × length) is on the roadmap — for now, use the table below.
| Pack Size | 5mm × 6mm Joint | 20mm × 10mm Joint |
|---|---|---|
| 600ml Sausage | 20 lineal metres | 4.4 lineal metres |
Product Brochure
Download Technical Datasheet
Full specifications, application systems, layering guides, and coverage tables.
Frequently Asked Questions
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