TL;DR:
- Older Malaysian factory buildings were not designed to carry solar loads. A structural pre-assessment by a PE-registered engineer is required before installation can proceed.
- The combined dead load of panels, racking, and cabling on a large industrial rooftop is typically around 0.16 kN/m², which can exceed the residual capacity of an ageing roof.
- 6 mandatory certifications govern any industrial solar system installation on an existing factory building in Malaysia: PE sign-off, UBBL plan submission, local authority approval, CIDB compliance, OSHA compliance, and a Certificate of Completion.
- Structural remediation — purlin replacement, added bracing — is a common and manageable outcome, not a project-stopping one.
- Build remediation costs into your ROI model from the outset. Proposals that omit this scope should be queried before commitment.
Most factory buildings in Malaysia were designed with a single structural brief: carry the roof, handle wind and rain, and stay standing. Solar was not part of that calculation. For a factory constructed 15 to 25 years ago under UBBL 1984 standards, the gap between its original specification and what a large-scale solar array demands is where industrial solar projects run into difficulty — a challenge research confirms affects older Malaysian buildings broadly.
This article is for factory owners, plant managers, and industrial property developers evaluating large-scale solar. It covers the structural requirements, certification sequence, and roof preparation steps you need to understand before any contract is signed.
What Makes an Ageing Factory Roof a Risk for Solar?
A roof with no visible leaks and no obvious sagging looks sound. For solar, that visual baseline is not enough.
A factory built under UBBL 1984 was designed to carry a defined dead and live load — with no allowance for the weight a solar array adds. On a large industrial rooftop, the combined load of panels, racking, and cabling is typically around 0.16 kN/m². After 15 or more years of tropical heat, UV exposure, and humidity, that loading can exceed whatever structural margin remains. The risk does not show up on a walk-around; it shows up in a load calculation.
Original drawings are the starting point for any structural assessment. For older Malaysian factories, they are often unavailable. Without them, a PE-registered structural engineer must survey the site, measure existing structural members, and build a new load model from observed conditions before feasibility work can proceed.
If your factory is more than 15 years old, a structural pre-assessment is the first line item in your project plan — not an optional preliminary.
The Structural Assessment: What It Covers and Why It Matters
The assessment is a formal engineering exercise with a written output — not a site visit with verbal feedback. It addresses 2 areas: load and structural capacity, and roof material condition.
Load Capacity, Wind Uplift, and Existing Documentation
Load calculations confirm whether your roof can carry the combined dead load of the mounting system and panels. Wind uplift is calculated separately; large-span factory roofs can experience significant upward forces during storms. The written report reaches 1 of 3 conclusions: the roof can carry the proposed solar load as-is; it can after specified remediation; or it requires major structural intervention. Each outcome is actionable — but only if the report is in hand before you commit to a contract.
Roof Material, Age, and Fixing Integrity
Roof material determines mounting method. Metal decking with a Klip-lock profile avoids penetration entirely. RC slab roofs accommodate ballasted racking. Older corrugated zinc sheet roofs often require replacement before installation — adding solar load to a compromised surface creates structural and waterproofing risks no mounting system fully mitigates.
Ask to see a defect schedule as part of the output — not just a pass or fail — so remediation scope is defined before work begins.
Ready to find out where your factory roof stands?
Before committing to a system size or payback model, request a structured pre-installation assessment from a certified EPCC contractor. A written structural report gives you the cost and timeline clarity you need to compare industrial solar proposals accurately.
What Certifications Does an Industrial Solar System Installation Require?
In Malaysia, 6 certifications and approvals are required in sequence for any industrial solar system installation on an existing factory building. Build all of them into your project timeline — PE certification and local authority approval alone typically add several weeks when not planned for in advance.
| Step | Requirement | What It Involves |
| 01 | Submit structural plans | Detailed drawings and load calculations submitted to the local authority under UBBL 1984 before work begins. |
| 02 | Obtain PE certification | A Professional Engineer registered with the Board of Engineers Malaysia certifies the roof can safely carry the solar load. Mandatory. |
| 03 | Secure local authority approval | The municipal council reviews and approves structural plans, confirming UBBL compliance. |
| 04 | Comply with CIDB requirements | Your EPCC contractor must hold valid Construction Industry Development Board registration. Verify before signing. |
| 05 | Meet OSHA standards | Compliance with the Occupational Safety and Health Act 1994 is mandatory throughout installation. |
| 06 | Obtain Certificate of Completion | Issued after installation. Required by insurers, building auditors, and future site buyers. |
How Do You Prepare an Ageing Factory Roof for Mega-Scale Solar?
Structural remediation is a common outcome of a pre-assessment — not a signal that a project is unviable.
Typical remediation work includes replacing or adding purlins, re-fastening sheeting, installing cross-bracing, or replacing deteriorated cladding. A well-managed EPCC process sequences this in parallel with system design and procurement, so structural and installation readiness arrive at the same point in the timeline.
Concentrate remediation on the zones where the array will be mounted. Build all remediation costs into your ROI model from the outset — omitting them produces a payback period that does not reflect reality.
Is Your Factory Roof Ready for Solar? Signs to Check Now
Knowing what to look for early prevents scope surprises once a structural engineer is on site.
From inside the building, look for:
| Indicator | What It Suggests |
| Water staining on purlins or ceiling structures | Active or past water ingress; potential ongoing structural degradation |
| Visible daylight through roof cladding | Cladding failure; likely waterproofing and fixing integrity issues |
| Sagging between support members | Load distribution problems; reduced residual structural capacity |
| Corroded or pitted steel members | Long-term humidity exposure; may affect load-bearing performance |
Each points to ongoing degradation that will affect the scale and cost of any preparation work required.
From your records, check whether any roof sections have been patched without a PE sign-off and whether original structural drawings are available. Informal repairs often create localised weak points a visual inspection alone will not identify.
Compile whatever documentation you have — drawings, repair records, utility bills — before your first meeting with a solar provider. The more context you bring, the more accurate their pre-assessment will be.
Start Your Industrial Solar System Installation with Northern Solar
A successful industrial solar system installation on an older factory begins with structural certainty — not panel counts or tariff calculations.
Northern Solar's EPCC process includes a structured pre-installation assessment covering roof condition, load capacity, and the full certification sequence before any system design is finalised. For factory owners and plant managers considering commercial and industrial solar solutions, this means your project moves forward with verified structural compliance, accurate costs, and a realistic timeline in place.
Contact us to schedule a site assessment. Our certified engineers will evaluate your facility's structural readiness, identify what preparation is needed, and give you a clear picture of costs and timeline before any commitment is made.
