NABL Accredited · NDT Service
Pull-Off Adhesion Strength Test of Plaster
(Adhesion Bond Strength)
In-situ measurement of the adhesion bond strength of plaster to concrete or masonry substrate using a hydraulic pull-off tester — verifying plaster application quality and substrate preparation adequacy.
BS EN 1015-12
Standard
±5%
Accuracy
24hr
Report TAT
NABL
Accredited
NABL Accredited Lab · ISO/IEC 17025:2017
Digital Reports via Autovity QLMS
Pan-India · 7 Lab Locations
Est. 2009 · 20,000+ Projects
Overview
What is the Pull-Off Adhesion Strength Test of Plaster?
The Pull-Off Adhesion Strength Test of Plaster measures the tensile bond strength between a plaster/render coat and its concrete or masonry substrate. A 50mm diameter steel dolly is bonded to the plaster surface, core-drilled around and subjected to a direct tensile pull-off force. The failure load and failure mode are recorded.
Conducted as per BS EN 1015-12 and IS 1661, pull-off adhesion tests are mandatory for façade plaster acceptance, external render systems, ETICS systems and any plaster application where bond failure would cause safety or durability issues. Global Lab uses calibrated hydraulic pull-off testers with digital load measurement.
Direct Bond Strength Measurement
Actual measured tensile adhesion — not estimated from visual inspection.
Failure Mode Classification
Distinguishes adhesive (interface) failure from cohesive (plaster) failure — critical for diagnosis.
50mm Core Drilling
Standard test uses 50mm core drill to isolate test area from surrounding plaster.
Acceptance Criterion Verification
Results compared against specification (typically ≥0.25 N/mm² for external render).
NABL Certified Reports
All results on NABL-accredited letterhead per BS EN 1015-12.
Grid Testing
Multiple test points across facade provide representative adhesion map.
Test in Action
Pull-Off Adhesion Strength Test of Plaster — Site Images
Bonded to Plaster Surface
Pull off Adhesion
Pull-Off Tester Applied
Test Procedure
How the Pull-Off Adhesion Strength Test of Plaster is Conducted
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1Dolly BondingA 50mm steel dolly is bonded to the plaster surface using two-part epoxy adhesive and allowed to cure for 24 hours.
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2Core DrillingA 50mm diamond core drill cuts through the plaster around the dolly to isolate the test area from surrounding plaster.
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3Pull-Off Tester AttachmentThe calibrated hydraulic pull-off tester is connected to the dolly via the coupling rod.
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4Load ApplicationTensile load is applied at a controlled rate of 0.05 N/mm²/s per BS EN 1015-12 until failure.
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5Result & Failure Mode RecordingMaximum load, calculated bond strength (N/mm²) and failure mode are recorded. NABL report within 24 hours.
Standards & Specifications
Applicable Test Standards
| Standard | Title | Scope | Type |
|---|---|---|---|
| BS EN 1015-12 | Methods of Test for Mortar for Masonry — Determination of Adhesive Strength of Hardened Rendering and Plastering Mortars | Pull-Off Test | British Standard |
| IS 1661 | Code of Practice for Application of Cement and Cement Lime Plaster Finishes | Plaster Application | Indian Standard |
| ASTM D4541 | Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers | Pull-Off Test | ASTM |
| BS EN 1542 | Products and Systems for the Protection and Repair of Concrete — Measurement of Bond Strength by Pull-Off | Bond Strength | British Standard |
Applications
Where is the CAPO Test Used?
External façade plaster acceptance testing on high-rise and commercial buildings
ETICS (External Thermal Insulation Composite System) adhesion verification
Internal plaster bond strength testing in hospitals, clean rooms and food facilities
Post-repair plaster bond verification after substrate preparation and application
Diagnostic testing of plaster delamination and hollow sounding areas
Quality assurance for premium residential and hospitality interior plaster finishes
Why Choose Global Lab
Our Advantages
NABL Accredited ReportsLegally valid adhesion certificates for all contractual and warranty requirements.
Failure Mode AnalysisWritten diagnosis of adhesive vs cohesive failure with remediation recommendations.
Grid Testing AvailableMultiple test points provide representative adhesion map for entire façade.
Pan-India CoverageField teams across 7 lab locations for rapid site deployment.
Fast TurnaroundTest results on site; NABL report within 24 hours.
Combined TestingPull-off + Carbonation + Cover depth as a complete façade assessment package.