A&A works in Singapore

A&A works in Singapore are approved in a defined order: clearances from the relevant technical departments, then URA planning permission under the Planning Act 1998, then BCA building plan approval under Building Control Act s.5, then a permit to commence structural works under s.6, then TOP or CSC.

First, a terminology warning

"Addition and alteration works" is not a defined term in the Building Control Act 1989. A&A is the industry label. What the Act defines is "building works", and A&A sits inside limb (b) of that definition. The only statutory definition of "addition and alteration works" found anywhere is in the Planning (Development of Land Authorisation) Notification, in a narrow agricultural-use context, which is not the sense anyone means on a project. So use A&A as the industry term, and anchor every argument about scope to the statutory definition instead.

Building Control Act s.2(1) defines building works as "(a) the erection, extension or demolition of a building; (b) the alteration, addition or repair of a building; (c) the provision, extension or alteration of any air conditioning service or ventilating system in or in connection with a building", and includes any fixed installation works and any connected site formation works. Related definitions that decide most arguments: structural works means works in relation to the structural elements of the building works; structural elements are those parts which resist forces and moments, including foundations, beams, columns, shear cores, structural walls, struts, ground anchors, slabs, trusses, staircases and load-bearing walls, but not doors, windows and non-load bearing walls; and key structural elements are the foundations, columns, beams, shear cores, structural walls, struts, ground anchors and any other parts essential for support and overall structural stability. On the planning side, Planning Act s.3(3)(e) provides that the demolition or reconstruction of, or addition to, a building constitutes development, which is what brings URA in.

The approval sequence, in dependency order

This is the order the work actually has to happen in on a conventional (CORENET 2) A&A project. Each step depends on the one above it, and the dependencies are written into the statute and the regulations, not just into agency practice.

1. Clearances from the Frontline Technical Departments. URA is explicit: "You may have to consult and seek clearance from relevant Frontline Technical Departments (e.g. LTA, NParks, NEA, FSSF, etc). You need clearance from them before applying for permission from URA."

2. URA planning approval under the Planning Act 1998. A Development Application, or Plan Lodgment where the project is eligible. URA states that it generally takes 20 working days to assess an application. Section 13(5) requires the competent authority to seek to determine an application within 3 months. A permission may first be granted as a provisional permission under s.17(1), which lapses 6 months after grant unless a longer period is specified; once its conditions are complied with within the validity period the authority must grant the written permission (s.17(4)). A written permission itself lapses if the development is not completed within 2 years (s.20(1)), extendable at the authority's discretion, and URA asks for extension applications 2 months before expiry.

3. BCA building plan approval under Building Control Act s.5. Applied for by the developer, accompanied by the fee, the particulars of the appropriate QP appointed to prepare the plans, the plans, an accredited checker's certificate for major building works, and the QP's prescribed-form certificate. BCA states plainly that "before applying for building plan approval, the QP must: Obtain written permission from the Urban Redevelopment Authority (URA)", and its structural plan submission requires "a copy of valid planning permission, lodgement receipt, or no-objection letter" from URA. The regulation behind that is BC Regs reg 4(1)(c), which requires the application to be accompanied by a copy of the notice of grant of written permission, or a copy of the lodgment receipt in lieu.

4. BCA permit to commence structural works under s.6. Applied for jointly by the developer, the licensed builder and the supervising QP, and granted jointly to all three, with a processing time BCA gives as 7 days. It can be applied for at the same time as structural plan approval or after the plans are approved. It is revocable if structural works are suspended for more than 3 continuous months, is non-transferable, and lapses automatically if any joint holder ceases to act or the builder's licence ceases.

5. SCDF fire safety plan approval, in parallel. This is an independent regime, not a sub-step of BCA's, and SCDF publishes no ordering rule relative to BCA plan approval: the two run separately and converge at TOP or CSC. Fire Safety Act s.56(1) makes it an offence to carry out fire safety works before the Commissioner has approved all the plans, or otherwise than in accordance with them, with a fine up to S$200,000 or imprisonment up to 2 years or both. A Fire Safety Certificate under s.60(1), or a temporary fire permit under s.60(3), is required on completion.

6. TOP or CSC under Building Control Act s.12, once the clearances listed in BC Regs reg 42(2)(fa) are in. See the certificate of statutory completion for how that gate works.

The dependency, stated precisely. Building Control Act s.5B(1) provides that a BCA plan approval automatically lapses when the written permission mentioned in s.12 of the Planning Act for development involving those building works lapses under s.20 of that Act; or, where no such written permission has been granted, at the end of a continuous period of 6 months during which the works are suspended; or if the works do not start within the prescribed period, which BC Regs reg 19 sets at 24 months from approval. Two things follow. Limb (b) shows the Act expressly contemplates a BCA plan approval existing without a written permission, for works that are not development. But where a written permission does exist, the building plan approval is parasitic on it, if the permission lapses, the approval lapses with it.

The cleanest statutory statement of the ordering is in the lodgment route. Paragraph 4(1)(l) of the Planning (Development of Land: Lodgment Authorisation) Notification requires that "prior to or together with the submission of any application to the Commissioner of Building Control for approval of the building plans", the plans, the required declaration and any written waiver are lodged with the competent authority with the fee. URA's published conservation A&A process runs the same way in six steps: Consult, Submit Plans to URA, Conservation Permission Issued, Submit Plans to BCA, Site Inspections, TOP or CSC Clearance.

The CORENET X nuance

Under the CORENET X gateway process the two approvals are issued at different gateways, and it is URA's Provisional Permission, not the Written Permission, that is the Design Gateway output.

So under CORENET X the URA Written Permission and the BCA Building Plan approval are concurrent outputs of the same gateway, not strictly sequential, while the Provisional Permission precedes them at G1. BCA's own website text, which says obtain the written permission before applying for building plan approval, reflects the traditional CORENET 2 model. Both are currently correct, for different project tiers. Do not let anyone tell you there is a single universal order.

Which tier you are in was reset on 23 July 2026 by circular APPBCA-2026-12 / URA/PB/2026/08-DCG, "Updates to CORENET X Implementation Plan". The current position: GFA of 30,000 m² or more has been mandatory since 1 October 2025; GFA of 5,000 m² or more becomes mandatory from 1 October 2026, scoped to erection of buildings with a total GFA of 5,000 m² or more, additions or extensions creating an additional GFA of 5,000 m² or more, and major A&A works with an affected or replaced GFA of 5,000 m² or more; and projects below 5,000 m² "will not be required to onboard the Gateway Processes. Submissions may continue to be made through CORENET 2 for now." That supersedes the 10 September 2025 circular, so anyone still saying CORENET X is mandatory for everything from 1 October 2026 is citing withdrawn guidance.

Most A&A is in any event an independent submission rather than a gateway submission: the published independent list includes "Independent Building Plan (BP) submission (e.g. A&A, change of usage...) not involving other agencies" and minor addition and alteration approval via lodgment. A Direct Submission Process also exists for simpler typologies, as a single stage approval prior to TOP or CSC. Its A&A criteria are worth checking against your scope: works within the existing building footprint; total affected GFA no more than 1,000 m² or 50% of the GFA of the existing building, whichever is lesser; no increase to refuse requirements; no new or increased restaurants; no new or increased M&E requirements; no new or increased pollutant generation; no building above a public sewer or within a sewer setback; no change in land use; additional used water discharge not exceeding 2 litres per second; no works affecting a common or public drain or a Drainage Reserve; and the railway protection zone conditions.

When approval is not needed at all

Three separate tests, and they are independent of each other. Failing one does not excuse the others.

• Is it development? Planning Act s.3(2)(a) provides that it is not development to carry out works for the maintenance, improvement or other alteration of a building "which do not materially affect the external appearance or the floor area of the building". That is the core internal renovation carve-out. Separately, para 2(1)(k) of the Planning (Development of Land Authorisation) Notification authorises the addition or enlargement, alteration or improvement of a detached, semi-detached or terrace house without permission, subject to strict conditions: the floor area of the addition or enlargement must not exceed a total of 20 square metres; it must not be effected on more than one occasion; it must not exceed the original height of the dwelling-house; except for an open car porch it must not extend beyond the front of the house or the approved building line; and it must not affect road widening proposals or obstruct the view of road users. That authorisation does not apply within a conservation area, ceases immediately on breach of a condition, and does not apply where a written permission condition prohibits the operation. URA also publishes a broader exemption list, subject to a universal caveat: it does not apply to premises gazetted as national monuments or conservation buildings, or located within conservation areas, envelop control areas, central areas, urban design areas, street block plan areas or other planning study areas.
• Is it insignificant building works? Building Control Act s.4(1)(d) with BC Regs reg 3A takes the works in the First Schedule outside Part 2 of the Act entirely, so no BCA plan submission is required. The Schedule includes creating an opening in a non-load-bearing wall or sealing one, the demolition, restoration or reinstatement of any non-load bearing wall, replacing windows and doors, replacing floor and wall finishes, lightweight false ceilings with no span exceeding 6 m, demolition of a suspended false ceiling, lightweight partitions not exceeding 10 m high, raised floors, and all air-conditioning works. BCA is clear that although plan submission and approval from BCA is not necessary, owners "must observe safety, and good practices, and obtain the required approvals from other relevant authorities".
• Is it lodgment works? BC Regs reg 3B and the Ninth Schedule list works whose plans are deemed approved on lodgment under s.5AA. Note s.5AA(4): the acknowledgment "is only evidence that the plans... have been lodged" and is not evidence that the plans comply.

The precision point most competing pages get wrong. Insignificant building works (First Schedule, reg 3A) fall outside Part 2 of the Act, so no BCA plan approval is required. Minor building works (Fourth Schedule, reg 12) still require plan approval; what they do not require is an accredited checker's certificate. Two different concepts, two different schedules, routinely conflated. And BC Regs reg 14(2) is worth keeping in your back pocket in a landlord and tenant argument: a plan approval does not confer title to land, does not act as a waiver of any term in any lease or licence, and does not permit any contravention of the Regulations.

Who prepares the plans, and who checks them

A qualified person under Building Control Act s.2(1) is "a person who is registered as: (a) an architect under the Architects Act 1991 and has in force a practising certificate issued under that Act; or (b) a professional engineer under the Professional Engineers Act 1991 and has in force a practising certificate issued under that Act". Section 8(1) requires the developer to appoint a QP to prepare the plans, a QP to supervise, a licensed builder, geotechnical engineers where applicable, and an accredited checker for the detailed structural plans and design calculations of major building works.

Which discipline is "appropriate" comes from the Third Schedule, the Scope of Professional Practice. Part I projects (retaining walls, site formation and foundations, bridges, tunnels, claddings and curtain walls, crane gantries, chimneys, marine structures and the like) are professional engineer only. Part II projects may be handled by either a professional engineer or an architect, and Part II expressly includes "(1) Alterations, additions and extensions to detached, semi-detached and terraced houses" and "(2) Alterations and additions within existing buildings which do not affect the building envelope". All other projects go to an architect, except structural components, which go to a professional engineer.

On accredited checkers, the single most useful rule on this page is Fourth Schedule para 2, which exempts from accredited checker certification "structural works consisting of repairs, alterations and additions to an existing building which do not materially affect the key structural elements of the building". So A&A needs no accredited checker unless it materially affects key structural elements. Where an accredited checker is required and the value of the building works is more than S$15 million, that checker must come from an accredited checking organisation, under para 2 of the 2008 Notification made under s.13(3)(a)(ii). The bare figure of S$10 million in s.13(3)(a)(i) applies only if no other sum is prescribed, and the 2008 Notification prescribes another sum, so do not use S$10 million.

Supervision thresholds sit in BC Regs reg 23A: building works valued at more than S$7.5 million are large building works requiring full-time site supervision; works valued at not more than S$7.5 million are small-scale building works. Regulation 24(1) then sets the team by value, from 1 resident technical officer above S$7.5 million up to S$15 million, through to 2 resident engineers and 3 resident technical officers above S$150 million, with the stage-based reductions in the regulation.

The two regulations that make the existing building the reference point

Regulation 5, plans of alterations and additions to buildings, is the single most important A&A provision:

"Where any building works consist of repairs, alterations or additions to an existing building and the qualified person who prepared the building plans has reasonable grounds for suspecting that the building works may affect the structural stability or integrity of the building, the building plans... must be accompanied by a certification from an appropriate professional engineer that: (a) he has inspected the building and investigated its overall structure; and (b) in his opinion, the building is capable or incapable of resisting the forces and moments which may be increased or altered by reason of the repairs, alterations or additions."

Where the QP who prepared the plans is himself a professional engineer in the appropriate discipline, he may provide the certification himself (reg 5(2)). Either way, that investigation needs member sizes, spans, grid positions and floor-to-floor dimensions of a building that may have no reliable drawings left.

Regulation 6 is the second hook. Plans must be prepared and signed by an appropriate QP and must "(e) demarcate clearly the new building works from the existing building by suitable markings; (f) delineate clearly the building works to be deleted, demolished or removed by suitable markings". You cannot demarcate new from existing against a building you have not measured. Regulation 8 adds the particulars, including the outline of the building in which the works are to be carried out marked in colour or otherwise, and the existing and proposed platform levels of the site and adjoining lots. Regulation 7 fixes paper scales at 1:10,000 for a key plan, at least 1:1000 for a site plan, and at least 1:200 for other plans. For demolition, reg 21(3) and (4) require the permit application to be accompanied by a method statement and an impact assessment report on surrounding buildings.

On the URA side, the Section I checklist requires the existing land profile indicated and highlighted in colour, existing ground levels for the subject site and adjoining sites immediately across the common boundaries, and typical cross-sections including existing and proposed ground levels. Item 35 requires professional engineer certification that existing structures to be retained are structurally sound and can accommodate the new works, for A&A and reconstruction of landed housing proposals retaining existing structures that do not comply with prevailing development control guidelines. URA's landed A&A lodgment asks for a Proposal Plan that is a "true cadastral and topographical representation" and a site coverage calculation plan that includes the existing building and the proposed extension. And its retention rule for existing non-conforming structures is a measured quantity, at least 25% of the existing floor plate must be retained, comprising an integrated wing of existing columns, beams, floor slab and external walls that includes the non-conforming portion of the house.

Conservation A&A is the one place a measured survey is a named submission requirement. URA requires "1 set of Measured Survey Drawings with registered Surveyor's endorsement" and "1 set of Structural Report from Professional Engineer". Read the endorsement requirement carefully: it names a registered surveyor. A scan, however accurate, is not a measured survey drawing for that purpose unless a registered surveyor endorses it, and it is not an as-built plan for Planning Act s.20A purposes unless prepared by a land surveyor who makes the required declaration.

The other agencies

The authoritative statutory clearance list for TOP and CSC is BC Regs reg 42(2)(fa), applied to TOP via reg 43(3)(ca). In summary it covers SCDF under the Fire Safety Act 1993, PUB for sewerage and drainage, NEA for environmental protection, LTA under the Street Works Act 1995, Parking Places Act 1974 and Electric Vehicles Charging Act 2022, NParks under the Parks and Trees Act 2005, URA for Common Services Tunnels Act 2018 conditions and the Planning Act s.24B(4) declaration, a market support services licensee for the electrical installation check, the Commissioner of Infrastructure Protection, and the Director-General of Public Health. Points worth knowing for A&A specifically:

• SCDF. "Fire safety works" expressly includes the installation, provision or removal of, or addition or alteration to, any fire safety measure, and "relevant works" captures the alteration, addition or repair of a building that involves combustible materials or affects the means of escape or the effectiveness of fire safety measures. The regulations are the Fire Safety (Building and Pipeline Fire Safety) Regulations, not the older "Building Fire Safety" title. Minor A&A listed in the Schedule to reg 4(4), in premises already holding a temporary fire permit or Fire Safety Certificate, go through QP certification and lodgement instead of full submission, subject to the para 4 disqualifiers and a limit of not more than 9 sprinkler heads. In all other cases SCDF requires plan approval before works begin. The strip-out side of this is covered on reinstatement in Singapore.
• NEA. Environmental Protection and Management Act 1999 s.33B(1) prohibits carrying out "controlled works" without a clearance certificate, and s.33 imports the Building Control Act definition of building works, which is what pulls A&A into the regime. The Environmental Public Health Act 1987 Part 5A does the same for controlled facilities, which include a toilet within any publicly accessible premises. NEA's lodgement scheme covers minor development projects, landed properties and minor A&A works to industrial developments.
• PUB. The statute was renamed: the Sewerage and Drainage Act 1999 is now the Sewerage, Drainage and Coastal Protection Act 1999 with effect from 29 May 2026, though the Building Control Regulations consolidation still uses the old name. Section 11(1) prohibits constructing, altering, discontinuing or closing up any sewerage system or earth retaining structure, or carrying out sanitary works, without clearance; s.14(1) prohibits erecting anything over, across or adjacent to a sewer. PUB's Simplified Submission route covers A&A to a single landed house, factory or shop where the works are within the existing building, subject to sewer setback, drainline, tank and discharge conditions.
• LTA. Railway protection rests on the Rapid Transit Systems Act 1995, not the Street Works Act, which is a common and consequential error. Street Works Act s.17(1) covers works on a public street.
• NParks. Parks and Trees Act 2005 s.14(1) prohibits cutting any tree with a girth exceeding one metre growing in a tree conservation area or on vacant land without approval, with a fine up to S$50,000.

When the existing drawings are wrong or missing

This is the situation most older-building A&A projects actually start in, and BCA says the necessary things in its own words on its guidance for building works not requiring approval:

• "Building owners can compare the as-built condition of the existing building works on their property with those in the approved plans to identify any unauthorised building works on your property."
• Owners found to have unauthorised building additions or alterations "will have committed an offence under the Building Control Act and will be subject to the appropriate enforcement action".
• The owner "should engage a Qualified Person (QP)... to act on their behalf and submit the plans of the unauthorised building works to the Commissioner of Building Control for approval", and the QP must also obtain all other necessary approvals, such as from URA.
• A legal search "does not guarantee that the property does not have any unauthorised structures", and owners who did not obtain the necessary approvals "can have the issuance of their Certificate of Statutory Completion (CSC) delayed".

Three statutory consequences follow, and they are the ones that cost money:

1. It can knock you out of the fast route. Paragraph 4(1)(j) of the Lodgment Authorisation Notification applies the lodgment route only if "no part of the existing landed dwelling-house comprises works that are unauthorised under the Act". An undocumented past alteration therefore pushes the project into a full Development Application.
2. It blocks the CSC. BC Regs reg 43(1) provides that a CSC shall not be issued where there are requirements still to be complied with, directions not fully complied with, departures or deviations from any approved or deemed approved plans, or incomplete works. Regulation 43(2) lets the Commissioner grant a TOP instead if satisfied the deviation is neither serious nor detrimental to the well-being or safety of occupants. That is the precise mechanism by which a documentation mismatch becomes a TOP rather than a CSC. It also matters during the works: under reg 2 and reg 18, material changes require submission to BCA for approval before construction, while immaterial changes, meaning changes that do not affect key structural elements or whose effects are localised and do not require a re-design, require only record plans and certificates on completion.
3. It surfaces at the next statutory inspection anyway. BCA Circular APPBCA-2026-02 of 2 March 2026 requires structural engineers conducting a Periodic Structural Inspection to report unauthorised structures, meaning building works not reflected in plans approved by the Commissioner, and to assess them including structural framing, area, and effects on the main building.

Start with retrieval. From BCA, BC Regs reg 49 allows a search and inspection of the approved or deemed approved drawings on payment of S$45, with a further S$65 for each set uniquely identified by a reference number; the BCA Plan Purchase System states the same figures and that BCA will contact the applicant within 10 working days on availability. Regulation 49A, for a S$45 fee, returns the date of issuance of the CSC or, where there are no records of that date, the TOP date, or the name of the QP appointed to prepare the plans, which often tells you which practice still holds the originals. From URA's Buy Planning Records service, a search is S$109 per address and approved plans are S$27.25 per set, with results in 10 working days and written consent from the property owner required; written permissions issued from 1990 onwards can be self-served through URA SPACE.

Retrieval closes part of the gap and rarely all of it, because BCA holds what was submitted, not what was built. Where the records stop, a measured record of the existing building is what feeds the reg 5 structural investigation, satisfies the reg 6(e) and (f) demarcation, evidences the 25% retention calculation, and lets you find the departures before an inspector does. Start with what to do when the floor plan is missing or wrong, then as-built documentation for the drawing set, or Scan-to-BIM where the design team needs a model rather than sheets.

The boundaries, stated plainly. A scan is not a building plan submission and cannot be submitted to BCA or URA in place of QP-prepared plans: only a Qualified Person may prepare and sign plans, and the Third Schedule dictates which discipline. It does not satisfy regulation 5, which requires a professional engineer to have inspected the building and formed a structural opinion; a survey supplies input to that opinion, it is not the opinion. It does not determine structural capacity, because it captures geometry, not reinforcement, concrete grade, connection detail or load path. It is not a measured survey drawing with a registered surveyor's endorsement for conservation A&A unless a registered surveyor endorses it, and not an as-built plan under Planning Act s.20A unless a land surveyor prepares it and makes the declaration. And it does not regularise anything: regularisation is a QP submission to the Commissioner of Building Control plus the other agencies' approvals. What accurate documentation does is reduce the risk of a mismatch being discovered late. That is a real benefit and it does not need overstating.

Statutory provisions cited above are on Singapore Statutes Online (Building Control Act 1989, the Building Control Regulations 2003 and the Planning Act 1998). Gateway scope and submission-package detail are published on CORENET, which is co-led by BCA and URA. Fees change: confirm them on the agency page before you budget.