
1. DESCRIPTION OF NON CONFORMANCE
During routine inspection and site audit, multiple non-conformances were observed related to plumbing, electrical installations, waterproofing, and drainage works. The works were found to be not complying with approved drawings, specifications, and relevant standards.
1.1 Incorrect Plumbing Installation
Water supply and sewer lines installed without proper gradient and support.
Inadequate pipe bedding and backfilling observed,
Pipe joints not sealed as per specification, leading to leakage risks.
As-built routing deviates from approved shop drawings without Engineer’s approval.
1.2 Incorrect Electrical Installation
Electrical conduits improperly embedded in concrete and structural elements without coordination with structural drawings.
Cable trays and trunking installed without proper spacing, support brackets, and earthing.
Junction boxes and manholes installed below flood level without waterproof enclosures.
M & E Consultant Notes :
What You Should NOT Include (Unless You Are the Electrical Designer)
Avoid full system design calculations such as:
Transformer sizing, full load demand calculation, harmonics analysis, coordination and discrimination curves,
These are the Electrical Consultant’s contractual responsibility.
For NCR or Case Study: Best Practice Approach
Include: Measured values, code limits, simple verification calculations, photos and test reports
Avoid:
Redesign proposals unless formally appointed, assumptions without measurement, guessing load profiles
1.3 Failure to Implement Waterproofing System
No waterproof membrane applied to underground utility chambers and culverts.
Inadequate joint sealing at pipe penetrations and construction joints.
Protective screed and drainage layers omitted in buried structures.
1.4 Neglect of Proper Drainage
Inadequate surface and subsoil drainage leading to water ponding.
Missing or blocked weep holes and subsoil drains.
Poor grading and compaction of backfill causing water accumulation around utilities.
.(Notes from RE and SC) - Drainage Flow Capacity Calculation - Surface and subsurface drainage design is typically based on the Rational Method for runoff estimation and Manning’s Equation for pipe capacity.
4. Drainage Failure Engineering Interpretation
Drainage failure typically occurs when:
Pipe diameter is undersized (Qpipe < Qrunoff)
Pipe gradient is flatter than recommended (S too low)
No subsoil drainage leading to hydrostatic pressure buildup
No waterproofing membrane causing seepage into structure
Inadequate discharge points or blocked outfalls
5. Engineering Implications of Poor Drainage
Structural Risks - Increased pore water pressure = reduced soil shear strength, foundation bearing capacity reduction, differential settlement and slab cracking
Building Envelope Risks - Rising damp and mould growth, corrosion of reinforcement, electrical system failure due to moisture ingress
2. REFERENCE
JKR Standard Specification for Building Works (JKR 20800)
JKR Arahan Teknik (Jalan) for road and infrastructure drainage
JKR Arahan Teknik (Jalan) 4/85 – Urban Drainage Design
JKR Standard Specification for Building Works (2014 & latest revisions)
JKR Guidelines for Drainage and Subsoil Drainage
JKR Standard Specification for Electrical Works
JKR Guidelines on Building Electrical Systems
SPAN Guidelines for Sewerage and Plumbing Installation
Malaysian Sewerage Industry Guidelines (MSIG)
Electricity Supply Act 1990 & Electricity Regulations 1994
ST Guidelines on Electrical Installation
MS IEC 60364: Low Voltage Electrical Installations
MS IEC 60502: Power Cables
MS IEC 60947: Switchgear and Controlgear
MS EN 12056 - Gravity drainage systems
MS EN 1992 / MS EN 1997 (Eurocode 2 & 7*) – Structural and geotechnical provisions
MS EN 12056: Gravity Drainage Systems Inside Buildings
MS 1228: Code of Practice for Sanitary Plumbing and Drainage
MS 1525: Building Services Energy Efficiency
BS EN 752: Drain and Sewer Systems Outside Buildings
BS EN 1610: Construction and Testing of Drains and Sewers
*Eurocode 7 (EN 1997): Geotechnical Design (drainage effect on soil parameters)
BS 8102 – Code of Practice for Protection of Structures Against Water from the Ground
BS 7671 (Electrical Installations and IET Wiring Regulations)
IEC 60364 Series
CONQUAS (CIDB QLASSIC) - QA/QC Team, HIRARC - HSSE Team
3. TECHNICAL IMPACT ASSESSMENT
3.1 Structural and Operational Risks
Leakage leading to soil softening and settlement of pavements and foundations
Electrical short circuits and system failures due to water ingress
Corrosion of metallic services and premature asset deterioration
Flooding of utility corridors and manholes
Public safety hazards and service disruptions
3.2 Engineering Consequences
Increased maintenance and lifecycle costs
Potential road subsidence and pavement failures
Non-compliance with statutory authority requirements (Local Authority, SPAN, TNB, JKR)
Contractual disputes and LAD exposure
4.0 ROOT CAUSE
5.0 CORRECTIVE ACTIONS
5.1 Plumbing Works
Reinstall pipes with correct gradient and bedding (sand/cement bedding).
Pressure test water lines and leakage test sewer lines.
Update as-built drawings and obtain Engineer’s approval.
5.2 Electrical Works
Reroute conduits away from critical structural zones.
Install proper earthing, supports, and waterproof enclosures.
Conduct insulation resistance and continuity testing.
5.3 Waterproofing
Apply membrane systems (bituminous, HDPE, or crystalline),
Seal all construction joints and penetrations with approved sealants,
Install protective layers and drainage boards.
5.4 Drainage
Install subsoil drains, geotextiles, and filter layers.
Regrade and compact backfill to design levels.
Ensure positive drainage to outfalls.
6. PREVENTIVE ACTIONS
Implement BIM coordination for M&E and Civil works.
Mandatory Inspection Test Plan (ITP) hold points for services installation.
Third-party waterproofing specialist engagement.
Training and certification for plumbing and electrical installers.
SCADA/IoT monitoring for water levels and leakage detection (for critical infrastructure).
7. RISK ASSESSMENT AND REGISTER UPDATES
This NCR highlights critical non-conformances that compromise structural integrity, public safety, and asset durability. Immediate corrective and preventive measures must be implemented to mitigate long-term engineering and contractual risks.


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