Part of our complete guide
A&A Works in Singapore: A Landed-Home Buying Guide →Key takeaways
- Start with the rooms and functions the purchase must deliver, then identify the assumptions each one depends on.
- Compare approved records with the actual property; a clean legal search alone cannot establish that every existing alteration is authorised.
- URA planning classification and BCA structural requirements answer different questions. Calling a project A&A does not settle either.
- A plan search is an input to a professional feasibility review, not proof that an extension or extra level can be built.
Find out what the house must be able to do
Before buying a landed house because you expect to extend it, commission a feasibility review of the changes that make the purchase worthwhile. The useful output is a written account of what has been checked, what remains unknown and what changes if an assumption fails.
Write down your essential outcomes first: perhaps a bedroom and bathroom on the entrance level, a larger family kitchen or space for a future lift. Separate these from preferences such as a particular facade or ceiling finish. A house that cannot deliver an essential function is a different proposition from one that merely needs a different design.
BCA advises potential buyers to have a competent person, such as an architect or engineer, inspect the property and compare its actual condition with approved plans. It also explains that a legal search reveals only unauthorised works already brought to its attention. Ask your conveyancing lawyer about the transaction and your appointed professionals about the building; neither enquiry replaces the other.
Sources: Building and Construction Authority: Building works not requiring approval
Build a records file before asking for a confident design
Ask the seller what records are available and arrange permission for professional access. Keep document references and dates together. If a drawing is missing or an area cannot be inspected, mark that gap explicitly instead of treating it as an empty box that someone else will resolve.
The table below is a suggested briefing structure. Each document establishes only part of the picture; the last column identifies the next question to commission.
Scroll across to compare all columns →
| Record or evidence | What the buyer can obtain or organise | What needs professional assessment |
|---|---|---|
| Planning history | Ask for Written Permission and its approved plans. URA's planning-records service accepts prospective-owner requests with the property owner's written consent. | Which approvals describe the relevant parts of the house, and what does that baseline mean for the proposed changes? |
| Approved building and structural drawings | Ask the owner to supply them or arrange an eligible BCA plan-purchase application. An authorised representative needs the specified owner documents and signed authorisation. | Does the available record match the house? What information or investigation is missing for assessing retained structure? |
| Land boundary information | Obtain the relevant SLA Certified Plan through INLIS. SLA distinguishes these final-boundary plans from provisional Registrar of Title plans. | Does the proposal depend on a boundary position that needs survey verification? Do not size an extension from the garden fence alone. |
| Drainage and sewer information | Arrange relevant PUB Services Plans through INLIS and give them to the design team. | The QP must verify site details. Sewer connections or common drains may be absent from the records; drainage levels also need checking. |
| Water services information | Include the Water Service Plan where relevant to the proposed works. | It shows approximate mains positions and may omit smaller connections. The team must establish the site information needed for the works. |
| Current condition and access | With permission, arrange an inspection and provide dated observations, available repair records and a list of inaccessible areas. | Which conclusions can be reached now, which need further investigation, and who will perform it? |
DirectHome editorial briefing matrix. It is a way to organise enquiries, not an approval checklist.
Sources: Urban Redevelopment Authority: Buy Available Planning Records · Building and Construction Authority: Types of applicants and supporting documents for approved-plan purchase · Singapore Land Authority: Survey Maps and Plans · PUB, Singapore's National Water Agency: PUB Services Plans
- URA planning-records service
Check available planning records and consent requirements.
- SLA INLIS
Access the relevant land and services information.
Ask two different questions about A&A
The first is a planning question: how will URA classify this particular proposal? Its landed-housing A&A guidance considers additional approved gross floor area, replacement of external walls, structural changes and roof changes. An additional storey is treated as reconstruction even if the floor-area increase is small. Staying below one percentage does not establish that a proposal qualifies as A&A.
URA also distinguishes previously approved structures that do not meet today's development-control guidelines from unapproved additions. Retaining a non-conforming part is conditional; its mere presence does not establish a right to rebuild it in the same place. Ask the planning QP which house-type and site-specific rules apply and what evidence supports retaining the parts your design relies on.
The second is a building-control question: what structural assessment, plan approval, checking and permit does the work require? BCA's structural process addresses those matters separately. Structural-plan applications require a QP who is a registered professional engineer in civil or structural engineering; A&A submissions can have different certification requirements according to their structural effects. A planning label is not a structural safety assessment.
Keep the professional roles explicit
Ask who is responsible for planning, structural design and any necessary survey work. Request a written explanation of the proposed approval route and unresolved assumptions. Do not accept a single unexplained 'A&A possible' statement as the feasibility result.
Sources: Urban Redevelopment Authority: Additions and Alterations to Landed Housing · Building and Construction Authority: Structural Plan submission
Turn the wish list into a decision table
Consider this hypothetical buyer: the house is attractive only if it can provide an entrance-level bedroom with a bathroom, while a bigger rear kitchen is desirable but negotiable. The buyer also wonders whether an extra level could be added later. These are three different decisions, so they should not disappear inside one renovation allowance.
Use a table like this at the briefing meeting. The status describes the evidence available, not an approval outcome.
Scroll across to compare all columns →
| Desired outcome | Assumption to test | Evidence or assessment to request | If it cannot be established |
|---|---|---|---|
| Entrance-level bedroom and bathroom: essential | A usable layout can fit and the bathroom can be serviced. | A measured layout option and professional review of the affected building and services work. | Reconsider whether the property meets the household's needs before relying on the renovation. |
| Larger rear kitchen: preferred | The extension can occupy the intended area. | A concept checked against the relevant planning baseline, boundaries, retained structure and services constraints. | Compare an internal replan or a smaller extension; record the lost function, not just a reduced floor area. |
| Additional level later: optional | Future expansion can be treated as a small A&A job. | A separate planning and structural feasibility question with its own assumptions. | Do not rely on this upside when deciding whether today's house is sufficient. |
Hypothetical decision exercise, not a DirectHome project or an assessment of any property.
Treat a missing record as uncertainty with an owner
If an existing enclosed space does not appear in the drawings supplied, first establish whether the record set is complete. Ask the professional inspecting the property to identify the discrepancy and the documents needed to resolve it. Avoid assuming either that the space is lawful because it is old or that one missing drawing proves it is unlawful.
The same discipline applies to physical information. PUB says the relevant services records need site verification before design; the drawing alone cannot settle all locations and levels. Agree what access or investigation the team needs and whether it can be arranged before your decision deadline.
For every open point, record the person responsible, the next action and the effect on your brief. 'Unknown' is a useful finding when it prevents an untested assumption becoming a promised room, price or completion date.
Sources: Building and Construction Authority: Building works not requiring approval · PUB, Singapore's National Water Agency: PUB Services Plans
Request a feasibility note you can actually use
A useful appointment should define what the review includes. Ask for a concise note that connects findings to your essential outcomes, rather than only a mood board or an overall construction estimate. The following is a suggested deliverable to agree with the team.
- Documents reviewed: reference, date and which parts of the property they cover.
- Inspection limits: areas accessed, information not verified and further work proposed.
- Options: what each concept delivers, what it compromises and the assumptions it still depends on.
- Professional responsibilities: who will assess planning, structure, boundaries and relevant services.
- Decision conditions: matters to resolve before relying on the concept, and how a negative finding changes it.
Bring the file to the next conversation
Send the address, house type, available drawings, permitted inspection access, your essential outcomes and unresolved questions when requesting an A&A consultation. State that you are still assessing a purchase. That makes it possible to discuss an appropriate feasibility scope before asking anyone to price an untested design.
Once the team has checked the critical assumptions, compare options against the same household brief. An internal replan, an extension and a more extensive reconstruction should be judged by the functions they deliver and the work they require. Keep any option that still depends on unavailable evidence clearly conditional.
- Discuss A&A works for a landed home
Bring your records and essential requirements to the consultation.
Sources and scope
Our editorial team checked the references below. Manufacturer guidance applies to the products and arrangements it describes; confirm the documents for your proposed installation.
- Building works not requiring approval
Building and Construction Authority · Checked
BCA's buyer guidance recommends professional inspection against approved plans and explains the limits of a legal search.
- Buy Available Planning Records
Urban Redevelopment Authority · Checked
Planning-record requests, available document types and property-owner consent requirements.
- Types of applicants and supporting documents for approved-plan purchase
Building and Construction Authority · Checked
Owner and authorised-representative eligibility and supporting-document requirements.
- Survey Maps and Plans
Singapore Land Authority · Checked
Certified and provisional boundary-plan distinctions and availability through INLIS.
- PUB Services Plans
PUB, Singapore's National Water Agency · Checked
Services-plan coverage, omissions and QP site-verification requirements before design.
- Additions and Alterations to Landed Housing
Urban Redevelopment Authority · Checked
Planning A&A criteria, additional-storey reconstruction classification and conditional retention of previously approved non-conforming structures.
- Structural Plan submission
Building and Construction Authority · Checked
Structural-plan applicant qualifications, permit process and additional certification considerations for A&A.
Related Services
Need Help With Your Project?
Get a free site assessment and no-obligation quote.
About the author
Written by the DirectHome team, Singapore home-upgrade contractors coordinating licensed lift, pool, roofing and gate specialists. We coordinate BCA-permitted works through licensed specialist partners across landed property in Singapore.