A&A works to or near conserved buildings and maintenance of conserved buildings

Circular No : URA/PB/2023/04-CUDG

Our Ref : DC/ADMIN/CIRCULAR/PB_23

CIRCULAR TO PROFESSIONAL INSTITUTES

Who Should Know:
Building Owners, Developers, Architects, Engineers, Building Specialists

Effective Date:
1 Mar 2023

A&A WORKS TO OR NEAR CONSERVED BUILDINGS AND MAINTENANCE OF CONSERVED BUILDINGS

1. This circular provides approaches to address structural issues that may be encountered when carrying out additions and alterations (A&A) works to or near conserved buildings^[1], particularly shophouses, to safeguard the integrity of the conserved building and its adjoining neighbours, and to remind building owners of their responsibility to regularly maintain their conserved properties. This is to safeguard the integrity of conserved buildings as well as that of the adjoining properties.

Addressing Structural Concerns about Conserved Buildings

2. The bulk of Singapore’s conserved buildings are old shophouses and terrace houses which used traditional construction methods and materials such as brick, timber, and stone, and have shared party wall structures. These historic structures are sensitive and prone to damage by vibration and ground movement.

3. New building works carried out, such as to the building façade, roof, party walls, floors, rear extension etc, could cause or exacerbate differential settlement between buildings, between the main building structure and its façade, and between adjacent building façades.

4. Building owners and developers should refer to the guidelines in Appendix A [PDF, 103 KB] ↗ (opens in new tab) for aspects typically considered when preparing to carry out structural works as part of A&A to conserved buildings or intending to carry out works on larger development sites near to conservation areas.

5. QPs submitting such A&A proposals for conservation buildings, sites next to conservation buildings, as well as for large development sites adjoining conservation buildings and areas should factor in the vulnerability of conserved buildings and propose appropriate structural and foundation system to comply with code requirements for the building use throughout its entire design lifespan.

6. QPs and builders should also propose restoration works and protective measures for the conserved building where appropriate. URA’s Conservation Technical Handbooks^[2] provide best practices and technical expertise on restoration works to better understand the nature of locally used materials, construction methods and restoration techniques for heritage buildings. A&A proposals to conserved buildings should also comply with Conservation Guidelines^[3].

7. Building owners should seek the necessary approvals from the relevant agencies if carrying out any building works, such as Conservation Permission^[4] from URA. If the works require structural modifications^[5], Structural Plan approval (and Building Plan approval where applicable) is also required from BCA.

Building Owner’s Responsibility to Ensure the Regular Maintenance of Their Buildings

8. Conserved buildings should be regularly maintained so that they remain structurally safe. Building owners and responsible parties such as Managing Agents play a key role for the timely maintenance of the structures, facades, and fixtures within their strata areas such that they are in a state of good and serviceable condition. When defects are left unchecked and unaddressed, the structural integrity of any building could potentially be affected, exterior features and appendages attached to building facades may dislodge and pose a safety risk to members of the public.

9. Some common tell-tale signs of defects are:

1. Spalling concrete, efflorescence, deterioration of structural connections

2. Cracks in brick piers, debonding of masonry units, beams, or facades,

3. Termite infestation or rotting of roof timber members,

4. Signs of water leakages or seepages such as water stains, delamination of plaster or bubbles observed in the wall paint, organic growth, water ponding, etc.

10. In such situations, we advise building owners to engage a Professional Engineer (PE) or other suitably qualified professional to implement the appropriate rectification work to address the root cause of the defect and prevent further deterioration.

11. Appendix B [PDF, 36 KB] ↗ (opens in new tab) presents requirements for periodic structural inspections and repair and maintenance to conserved buildings.

12. Should you need any clarification, you may contact the following agencies:

Thank You.

ER. DR YET NAI SONG
DIRECTOR
FOUNDATION ENGINEERING DEPARTMENT
For COMMISSIONER OF BUILDING CONTROL
BUILDING AND CONSTRUCTION AUTHORITY

ANG KAH ENG, KELVIN
DIRECTOR
CONSERVATION MANAGEMENT
For CHIEF EXECUTIVE OFFICER
URBAN REDEVELOPMENT AUTHORITY

^{[1] The location of conservation areas and conserved buildings are available online at go.gov.sg/uraconsportal} ↗ (opens in new tab)

^{[2] Conservation Technical Handbooks are available online at https://go.gov.sg/conservationbestpractices} ↗ (opens in new tab)

^{[3] The Conservation Guidelines set out allowable works to retain the essential architectural features and spatial characteristics of the buildings while allowing flexibility for adaptive reuse, they are available online at https://go.gov.sg/conservationguidelines} ↗ (opens in new tab)

^{[4] Requirements for A&A submission to obtain URA’s Conservation permission and the definition of Category of Works (Category 1, 2 & 3) are available online at https://go.gov.sg/conservationadditionsalterations} ↗ (opens in new tab)

^{[5] New or Modification of structural works not exempted under insignificant building work requires BCA submission. Please refer to https://www1.bca.gov.sg/public/general-public/building-works-that-do-not-require-plan-submission-to-bca} ↗ (opens in new tab) ^{for more information on insignificant building works.}