The Construction Quality Assessment System (CONQUAS), introduced in Singapore since 1989, serves as a national standard for assessing the quality of building projects.

CONQUAS® was designed with three objectives:

1.    To have a standard quality assessment system for construction projects

2.    To make quality assessment objective by measuring constructed works against workmanship standards and specification, and using a sampling approach to suitably represent the whole project

3.    To enable quality assessment to be carried out systematically, within reasonable cost and time

Today, CONQUAS® is a widely recognised and internationally accepted benchmarking tool for quality. CONQUAS® is a registered trademark in Singapore, Malaysia, China, Hong Kong SAR, United Kingdom, Australia, South Africa and India.

Amendments to CONQUAS®

CONQUAS® is periodically fine-tuned to keep pace with changes in technology and quality demands of an increasingly sophisticated population:

·      CONQUAS® 21– Launched in 1998 to introduce new features and refinements to make CONQUAS® scoring more comprehensive and customer-oriented.

·      CONQUAS® 9th Edition– Launched in November 2017 to promote the adoption of Design for Manufacturing and Assembly (DfMA) which supports both high quality and productivity, and to ensure the score commensurate with end users’ expectations on workmanship quality.


  • The 3-tier CONQUAS® Scheme will apply to all CONQUAS® applications for private residential projects received on and after 9 October 2019.
  • The scheme aims to help developers/contractors further raise the quality of their projects by covering more samples and identifying more areas for improvement. 
  • The 3-tier CONQUAS® Scheme is applicable to developers/contractors as shown in the table below

1 Additional samples will be taken on: architectural internal finishes samples, wet areas water tightness tests for toilets/bathrooms and window water tightness tests.
2 100% checks refer to the same regime of inspection as QM. Projects will be required to meet a higher CONQUAS score set at the bottom 40th percentile CONQUAS score of private residential developments shown below.
3 The initial CONQUAS score will be derived after 20% (for tier 2a) and 50% (for tier 2b) of the required architectural internal finishes samples are completed.
4 The threshold CONQUAS score is set at the bottom 10th percentile CONQUAS score of private residential developments shown below.
5 Major defects refer to defects that would generally not be acceptable to end-users as specified in the guide on "Construction Quality Assessment System (CONQUAS)" available on BCA's website.

a. The bottom 10th percentile CONQUAS score for FY 2020 is 86.4
b. The bottom 10th percentile CONQUAS score for FY 2021 is 86.4
c. The bottom 40th percentile CONQUAS score for FY 2020 is 93.3
d. The bottom 40th percentile CONQUAS score for FY 2021 is 93.3
e. Private residential developments include private mixed developments with residential component

·      CONQUAS 2019 (latest edition) – Launched on 20 Dec 2019 to provide greater emphasis on architectural quality and water seepage issues including upstream checks at factories for prefabricated prefinished volumetric construction (PPVC) projects. In this latest edition, the CONQUAS framework was simplified with the streamlining of the building categories and removal of assessments on regulated structural and Mechanical, Electrical and Plumbing (MEP) works.

How do companies benefit

By submitting their projects for CONQUAS® assessment, companies can look forward to:

·      Benchmarking of its workmanship quality against CONQUAS® standards
·      Increased client confidence and competitive edge when you consistently deliver projects with high CONQUAS® scores
·      Better marketability and enhanced corporate image with a good CONQUAS® score track record

Assessment approach

The assessment consists of 3 main components:

1.             Structural Works
2.             Architectural Works
3.             Mechanical & Electrical (M&E) Works

Each component is further divided into different items for assessment. The sum of the 3 components will give the CONQUAS® score for the project.

Weightages – Weightages for Structural, Architectural and M&E works are allocated according to four categories of buildings: (a) Commercial, Industrial, Institution & others, (b) Private Housing, (c) Public Housing, and (d) Landed Housing.

Site inspection – Buildings are assessed primarily through site inspection. The assessment is done throughout the construction process for Structural and M&E Works and on the completed building for Architectural Works. The assessment also includes tests on the materials and the functional performance of selected services and installation; this helps to safeguard the interest of building occupants in relation to safety, comfort and aesthetic defects.

Sampling – As it is impractical to assess all elements, CONQUAS® uses a sampling system which is based on the size of the building. The samples shall be distributed as uniformly as possible throughout the construction stages.

Scoring – The scoring will be done on the works that are inspected for the first time. Rectification and correction carried out after the assessment will not be re-scored. The objective of this practice is to encourage "doing things right the first time".


The manual provides detailed information on the assessment, including:

1.    The components to be assessed and their weightages according to the 4 categories of buildings
2.    Assessment approach for each component
3.    Quality Standards: List of elements that will be assessed

Download the CONQUAS 2022 Manual (PDF, 1.0MB)
Download the CONQUAS 2019 Manual (PDF, 1.0MB)
Download the CONQUAS Manual - 9th Edition (PDF, 1.0MB)
Download the CONQUAS Manual - 8th Edition (PDF, 1.0MB)

How to apply
View application procedures

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