Selecting a wet-works specialist.
Structural alterations, plastering and tiling, and exterior water repairs are three different competences — not one. This register is the checklist ALUMAX runs before appointing a wet-works specialist: classify the work, verify the contractor, fix the method, and gate the inspections.
This is an internal selection framework, not a legal instrument or an engineering opinion. Structural classification, submission and approval are the submitting professional’s or engineer’s responsibility. Review it with a Sarawak construction lawyer and the appropriate engineer before it drives any contract, demolition or customer terms.
Do you need one specialist, or three?
The first decision is whether you genuinely need one wet-work specialist for all three scopes. A competent plastering or tiling contractor should not automatically be trusted with structural alterations or exterior water-ingress repairs — split the scopes and match each to the right competence.
Openings, extensions, foundations, retaining walls, beams, columns and slabs. Engineering design, review and approval come before any demolition — never automatically the finishing contractor’s call.
Plastering, screed, tiling and stone. A competent finishing contractor — but competence here does not qualify them for structural or water-ingress work.
Façade cracks and movement, waterproofing, roof and balcony falls, outlets and drainage — diagnosed and treated as one water system, not a repaint.
Classify structural and non-structural work correctly
ALUMAX should requireMark every item as structural, non-structural, exterior-envelope or uncertain. Structural openings, extensions, foundations, retaining walls, beams, columns and slabs require engineering review.
Common trapContractor describes structural demolition or cutting as “minor hacking” to avoid drawings and approval.
Check registration, grade and permitted work category
ALUMAX should requireValid CIDB registration with an appropriate category, grade and specialisation for the contract value and scope. Confirm worker and site-supervisor registrations where applicable.
CIDB registration requirementsCommon trapContractor shows only an SSM registration, an expired CIDB certificate or another company’s certificate. CIDB registration is generally mandatory before undertaking construction work in Malaysia.
Choose the actual team — not only the company
ALUMAX should requireName the project manager, site supervisor, foreman and subcontractors. For structural work, identify the engineer responsible for design and inspection.
Common trapA strong company portfolio is presented, but the project is passed to an inexperienced crew or an uncontrolled subcontractor.
Verify experience by work type
ALUMAX should requireRequest comparable completed projects separately for structural concrete, masonry / plastering, waterproofing and exterior façades. Check projects after at least one rainy season where possible.
Common trapAttractive completion photographs conceal cracks, hollow render, water ingress and drainage failures that appeared later.
Require a proper condition survey and diagnosis
ALUMAX should requireRecord cracks, movement, dampness, corrosion, delamination, floor levels, drainage and existing structure before quotation. Determine the cause, not only the visible defect.
Common trapContractor patches a crack or paints over dampness without identifying structural movement, failed waterproofing or external water entry.
Approve the method and construction sequence
ALUMAX should requireA method statement covering hacking, temporary support, reinforcement, formwork, concrete placement, curing, masonry, waterproofing, plastering and protection.
Common trapContractor removes walls or concrete before providing temporary support, or closes surfaces before hidden work is inspected.
Control hidden materials and system compatibility
ALUMAX should requireSchedule cement, sand, concrete grade, reinforcement, blocks, mortar, mesh, waterproofing, primers, adhesives, sealants, anchors and repair systems. Record who supplies each item.
Common trapVisible ALUMAX materials receive attention while cheap concealed materials decide whether the installation eventually fails.
Set measurable workmanship and testing criteria
ALUMAX should requireApproved mock-up, alignment and flatness tolerances, reinforcement inspection, concrete test requirements, waterproofing flood test, pull-off tests where appropriate, drainage test and photographic records.
CIDB QLASSICCommon trapAcceptance is based on whether the work “looks okay.” Hollow tiles, weak plaster, poor curing or incomplete waterproofing stay hidden. CIDB’s QLASSIC framework exists to make workmanship assessment more objective.
Resolve exterior water, movement and access properly
ALUMAX should requireFaçade crack treatment, movement joints, flashing, copings, roof / balcony falls, outlets, sealant joints, the paint / coating system, scaffolding and protection from rain during the work.
Common trapExterior renovation becomes a repainting exercise. Water-entry paths, failed joints and insufficient drainage remain untreated.
Choose a complete contractual and warranty package
ALUMAX should requireA detailed scope, exclusions, quantities, variation rates, payment milestones, insurance, defect period, workmanship warranty, test records and as-built handover.
Common trapA vague lump sum, an excessive deposit, verbal variations and a “five-year warranty” that excludes the substrate, water ingress and consequential damage.
Who is technically responsible
ALUMAX controls the visible supplied materials; the partner specialist specifies, installs, tests and warrants the concealed work — under the agreed contract.
| Work category | Technical responsibility |
|---|---|
| Structural foundations, beams, columns, slabs and load-bearing walls | Engineer designs and specifies; a registered contractor executes; inspections occur before concealment. |
| Structural openings and extensions | The approval path and engineering are resolved before demolition. |
| Brick / block partitions | The wet-work specialist verifies setting-out, ties, lintels, services and movement joints. |
| Screed and plaster | The specialist controls substrate preparation, mix, thickness, levels, curing and crack treatment. |
| Tiling and stone | The specialist controls substrate, setting-out, adhesive, joints, falls and lippage. |
| Waterproofing | A named waterproofing specialist owns preparation, application, penetrations and flood testing. |
| Exterior render and coating | A façade specialist diagnoses cracks, moisture and movement before finishing. |
| Roof, balcony and external drainage | Waterproofing and drainage are treated as one coordinated system. |
| ALUMAX-supplied visible materials | ALUMAX controls SKU, format, colour, quantity and intended appearance. |
| Concealed materials and workmanship | The partner specialist specifies, installs, tests and warrants them, subject to the agreed contract. |
Do not let work continue past these without inspection
- 1After hacking, before repair or reconstruction
- 2After reinforcement and formwork, before concrete
- 3After concealed pipes / conduits, before plaster or screed
- 4After waterproofing, before covering
- 5After screed / falls, before tiles
- 6After crack repair, before exterior coating
- 7Before removing scaffolding or access equipment
- 8Before final payment
The most dangerous trap is letting the wet-work contractor decide that engineering or approval is unnecessary. That decision should sit with the appropriate submitting professional or engineer — not with the person pricing the construction work.
For Sarawak projects, structural alteration and addition work should be checked against the required local-authority and professional submission process. The Sarawak Buildings Ordinance addresses structural elements, alterations and engineer-led investigation of structural integrity. Sarawak Buildings Ordinance
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