Roof Installation in Singapore: A Practical Guide

A roof replacement is a major job and a poor one leads to leaks that are expensive to trace. This guide explains the process for homeowners and property managers in Singapore. It is general information, not professional advice, so confirm details with a qualified roofing contractor and, where needed, a Qualified Person (QP).

Choosing roofing materials

Common choices in Singapore are concrete tiles, clay tiles and metal roofing. Weigh these factors:

• Durability: The material must cope with heavy rain, humidity and strong sun.
• Cost: Compare the installed price and the long-term maintenance cost, not just the price per square foot.
• Weight: Heavier materials need a stronger roof structure.
• Appearance and building type: The material should suit the building and, for some estates, any design guidelines that apply.
• Maintenance: Ask what upkeep each material needs.

Finding a reliable contractor

• Ask friends, neighbours and your property manager for recommendations, and read independent reviews.
• Get at least three written quotes. Compare the scope of work, materials, thickness, brands, timeline and warranty, not only the price.
• Ask for proof of insurance, including work injury compensation cover for workers, and for the company's registration details.
• Ask for references and, if possible, look at recent jobs.
• Check that the contractor understands working-at-height safety requirements. Falls from height are a leading cause of workplace deaths in construction, so a contractor who takes safety seriously protects you as well as their workers.

Approvals and regulations

Whether you need approval depends on the work. According to BCA and URA guidance, additions and alterations to landed houses that involve structural works generally need BCA approval through a Qualified Person, and URA's guidelines cover changes to roofs within the scope of additions and alterations. Replacing a roof like for like may not need structural approval, but changing the structure, adding a storey or affecting the drainage reserve can. HDB flat owners should check with HDB before any work that affects the roof or common areas. Condominium and strata developments are governed by the management corporation. Ask your QP or the relevant authority before the work starts, and do not rely only on the contractor's assurance.

Preparing the property

1. Clear furniture and outdoor items from around the work area.
2. Tell neighbours before noisy work begins.
3. Confirm with your contractor who is responsible for permits and approvals.
4. Cover or move belongings that dust or falling debris could damage.

The installation process

The steps vary by material, but a typical roof replacement includes:

1. Removing the old roof: Stripping old tiles, sheets or other covering. Roofs built decades ago may contain asbestos-cement sheets; if so, removal must follow the legal requirements, so ask the contractor how they will handle this.
2. Inspecting and repairing the structure: Checking the roof deck, rafters and battens for damage.
3. Waterproofing: Installing an underlayment or membrane.
4. Fitting the roofing material: Following the manufacturer's installation guidelines.
5. Flashing and ventilation: Sealing joints and edges and providing ventilation so moisture does not build up.
6. Final inspection: Check the work against the agreed scope before final payment.

Maintenance after installation

• Inspect the roof periodically for cracked tiles, loose fixings and leaks, and after storms.
• Clear leaves and debris from the roof and gutters so water flows freely.
• Keep gutters and downpipes clean.
• Arrange professional servicing from time to time. Never climb onto a roof without proper safety equipment.