A&A Contractor in Singapore

Weima Builders is an A&A contractor in Singapore for building owners, facility managers and businesses that need to change, extend or upgrade an existing building. We are registered with BCA under CW01 General Building at grade A1 and hold a General Builder Class 1 licence. Our team handles additions and alterations works for commercial and industrial buildings, from structural changes and roof gardens to fit-out. So one main contractor runs the job from first review to handover.

Request a consultation or call +65 6548 3000 to talk through your building.

What Do Our A&A Works Cover?

A&A stands for additions and alterations. In short, it means changing a building that already stands. Our building services cover the trades this work needs. Then we shape the scope around your brief.

• Structural works, such as new openings, added floors or strengthening.
• Architectural works, so walls, roofs, doors and finishes.
• Roof gardens and rooftop works, if your roof can take the load.
• Interior fit-out for commercial and industrial space.
• M&E works, which we plan with your engineers.
• Design and build, if you want one contract for design and works.
• Upkeep and operations support after handover.

Also, A&A work carries more unknowns than a new build. For example, old drawings may not match what is on site. So we check the building early and raise gaps before they cost you time.

Who Needs an A&A Contractor?

Most of our commercial A&A clients fall into four groups:

• Building owners who want to add space, upgrade a roof or refresh a facade.
• Facility managers who need works done while the building stays in use.
• Business owners who lease space and then need it fitted out.
• Industrial owners who change a layout to suit a new process.

However, each group has different limits. For example, a tenant may need the landlord’s consent first. In contrast, an owner may need to keep staff and visitors safe during works. Because of this, we agree access, noise and safety rules before we start.

How Do We Deliver A&A Works?

Our method follows the five stages in our process. Each stage ends with a clear output.

1. Concept. First, we review your brief and visit the site with your team. Then we note what the old drawings miss.
2. Development. Next, we work with your architect and engineers on structure, loads and services.
3. Documentation. Then we give your Qualified Person (QP) the builder inputs the authorities ask for.
4. Execution. After that, our project managers run the site, trades and safety. Also, we phase work to suit your operations.
5. Testing. Next, we test systems and close out defects before the final checks.
6. Handover. Finally, we hand over the space with records for your facilities team.

So you deal with one point of contact, and nothing falls between trades.

Which Approvals Apply to A&A Works in Singapore?

Not every A&A job needs the same approvals. Your QP confirms the route and submits the plans. Then we handle the builder’s part and keep the site ready for each check.

First, URA lists the works that do not need planning permission. For example, internal partitions in a non-residential building are exempt if there is no change in primary use, quantum or floor area. However, works that materially change the outside look or floor area fall outside that list.

Next, BCA needs a permit for most works. BCA states that an Accredited Checker must certify A&A works that materially affect key structural elements, such as strengthening. Also, the developer, QP and builder apply jointly for the permit.

Then there is fire safety. For minor works, SCDF’s lodgement scheme lets a QP lodge plans before work starts. Also, the tenant must get the owner’s or MCST’s consent first. On JTC land, JTC needs to consent to A&A, though some works are exempt. If a new industrial process comes in, NEA’s siting consultation applies. Finally, LTA has a form for changes to parking lots.

CORENET X for major A&A

Also, the URA and BCA circular of 23 July 2026 makes CORENET X mandatory from 1 October 2026 for larger jobs. It covers major A&A works where the affected or replaced GFA is 5,000 sqm or more. So big upgrades now pass through the CORENET X gateways.

Which A&A Projects Have We Done?

These jobs show the kind of A&A construction we take on. For more, see our project references.

So both jobs meant working inside an existing building.

What Credentials Do We Hold?

Credentials show if a builder can take on your scope.

So what does this mean for you? First, BCA states that a builder licence is needed where plans need approval by the Commissioner of Building Control. Also, a Class 1 licence covers projects of any value. To compare builders, read how to choose a BCA A1 general builder. Then see our note on BCA contractor grades. For industrial sites, our warehouse approvals guide may also help.

How Do You Start an A&A Project?

Ready to plan your A&A works in Singapore? First, send us a few details:

• The building address and the floor or unit.
• Existing drawings, if you have them.
• Your target start and finish dates.
• The affected GFA and a short note on what will change.

Then call +65 6548 3000, email info@weima.sg or use our contact form. Our office hours are Monday to Friday, 8.30am to 6pm.

Frequently Asked Questions

Sources:

• URA, Works exempted from planning permission
• BCA, Structural plans and permit approvals
• SCDF, Minor addition and alteration works
• BCA, Permit for structural works
• JTC, QP submission and plan consent
• URA and BCA, Updates to CORENET X Implementation Plan (23 July 2026)
• NEA, Industrial Siting Consultation
• BCA, Builder licensing
• LTA, Requirements for vehicle parking proposals