Q1 What would happen if I do nothing about the unauthorised additions and/ or alterations on my property?
A1 To have unauthorised building additions and/ or alterations on your property may pose a safety hazard if the structures were not properly designed by a QP. Furthermore, it is also an offence under the Building Control Act and you will be subject to enforcement action, where appropriate.

Q2 How would I know if there are unauthorised building works on my property?
A2 To verify the presence of such building works on your property, you can compare the as-built conditions of the work against the approved plans.

Q3 How can I obtain a copy of the approved plans?
A3 As a property owner, you can submit an online application under e-Services in BCA website at Please choose “Application for Inspection and Making copies of Approved drawings”, and attach the essential supporting documents in the application.

The accepted essential supporting documents as documentary proof of ownership of a property are:
(i) Title Deed or Latest Property Tax Statement from an existing property owner;
(ii) Notice of Transfer or Certificate of Stamp Duty from a prospective owner who bought the property not more than 3 months

After your submission, a search outcome will be emailed to you in 5 working days. If drawings are available, you will need to bring your identity card and come personally to view and purchase the required plans at BCA HQ Service Centre, 6th storey, 52 Jurong Gateway Road Singapore 608550.

Alternatively, as a property owner, you may provide an authorization letter with either one of the above documentary proof of ownership for your authorized person to apply, view and purchase the approved drawings.

Q4 How can I regularise the unauthorised building additions and/ or alterations works on my property?
A4 You should engage a Qualified Person (QP) who is the project architect or professional engineer to act on your behalf and submit the plans of the additions and/ or alterations works, to the Commissioner of Building Control for approval. All other necessary approvals such as those from the URA and relevant authorities, must also be obtained.

Q5 What should a potential buyer do to ensure the existing property is free from unauthorised structures?
A5 A potential buyer who is buying an existing property should check to ensure that it is free from unauthorised structures. Although legal search is one of the checks being routinely done by a conveyancing lawyer, such search alone does not necessarily ensure that the property is free from unauthorised structures. A routine legal search will only surface those unauthorised structures that have already been brought to BCA’s attention. It is thus more appropriate for a potential buyer to engage a competent person (for example, an architect, engineer or building surveyor) to investigate whether the property is free from unauthorised structures by carrying out a site inspection and checking against approved plans.

Q6 What should a new property owner be aware of before proceeding with the addition and/ or alterations to the new property?
A6 Quite often, new owners would proceed to carry out additions and/ or alterations to their new property soon after they have obtained their keys to their properties. If the planned additions and/ or alterations require BCA approval, but are carried out without the necessary approval, they can delay the issuance of the Certificate of Statutory Completion (CSC). Thus it is important that new owners limit their alteration works to those which do not require BCA approvals (as illustrated in this guide) and check with the developer and project architect or professional engineer before carrying out any other major addition and/ or alteration works.