Additions and Alterations (A&A)

Premium Addition and Alteration (A&A) works in Singapore


We are a team of professionals and creators specialising in landed house renovation in Singapore, offering full-scope, Design & Build tailored to your needs. Whether you're looking to make small updates or undertake a major overhaul, we have the experience to help you achieve your goals.

We’re passionate about turning houses into homes by creating beautiful, functional spaces that truly reflect your lifestyle. Whether you need more room for your growing family, want to refresh your layout, or dream of a complete home transformation, we’re here to bring your vision to life. With our expertise in A&A works in Singapore, we ensure every project is tailored to your needs, delivering quality craftsmanship and seamless renovations.

 The Importance of Experience in Addition and Alteration Works

As a landed homeowner, you may be eager to get started on your renovation or additions in Singapore. However, it's important to take the time to carefully consider your plans and make informed decisions. That's where an experienced company like Haus Atelier comes in. Houses are at the forefront of our business - and we have a team that is trained in Design, Architecture and Structure coupled with the knowledge of local compliances and requirements to aid in your process.

We can help you navigate the often grey and unusual process, ask the right questions, work with the necessary experts, and explore different scenarios to ensure you are making the best possible choices for your home improvements and alterations.

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what is addition and alteration(a&a) works?

​A&A stands for 'Additions & Alterations’ to a building. As the name suggests, it denotes derivations to the existing building involving significant changes (but not more than 50%) to either one of the following:

Gross Floor Area
External Walls ( Facade)
Structure
Replacement of Roof without involving an additional storey
Addition of Attic ( provided GFA is less than 50%)

As a BCA licensed GB1 builder, we are fully equipped to handle the necessary applications and approvals from the necessary Authorities. Trust us to deliver the best A&A works that money can buy and create a beautiful, functional space that exceeds your expectations.

Haus Atelier
Addition & Alteration (A&A) Services

authorities submissions & compliance

Spatial Planning and Curation

Construction & Project Management

Interior design detailing and styling

What is Reconstruction?

Reconstruction is a major overhaul of a property, often comparable to a full rebuild. The key distinction is that if more than 50% of the building’s structure and facade is altered, it is categorized as Reconstruction rather than A&A.

When it comes to landed property renovations in Singapore, homeowners often find themselves confused between Addition & Alteration (A&A) and Reconstruction. While both involve significant changes to a property, the key difference lies in the extent of modifications.

At Haus Atelier, we help homeowners navigate these classifications, ensuring that your project aligns with your design vision, budget, and regulatory requirements.

This means stricter compliance with BCA regulations.

Similar submission and approval processes as a rebuild 

In some cases, this can be waived if the existing structure cannot accommodate it.

potential requirement for a household shelter 

  • Adding a new floor & changing facde
  • Extending or altering structural elements
  • Making Substantial changes to building facade
  • Changes to the envelope control in a major way - ie side extensions + new floors etc.
  • Removal of ground beam to remove split level in traditional landed houses where the living and dining is split.

Since Reconstruction follows similar regulatory pathways as a rebuild, it requires a more intensive approval process, longer project timelines, and higher costs. 

major changes include:

Understanding the Difference:
A&A vs. Reconstruction

A&A vs. Reconstruction: What Sets Them Apart?

What is Addition & Alteration (A&A)?

A&A is a light-touch revamp that allows for extensive upgrades while maintaining the existing structure and framework of the house. Key characteristics of A&A projects include:

The foundation, primary beams, and columns are not significantly altered ( Less than 50% affected)

Structural integrity remains SOMEWHAT intact

No major relocation of essential infrastructure.

Sewerage and envelope control remain unchanged

  • Adding a home lift
  • Modifying the staircase design
  • Roof modifications
  • Constructing a new swimming pool

While A&A projects can involve substantial modifications, they must not exceed 50% of the total structural and facade changes. Once they do, the project may be classified as a Reconstruction instead.

Common A&A works:

How Haus Atelier Can Help

The totality of changes determines whether your project falls under A&A or Reconstruction. For instance, if you plan to:
  •  Add a lift – A&A
  •  Modify the roof – A&A
  • Add a new floor + a lift + modify the roof – Reconstruction (as total modifications exceed 50%)
At Haus Atelier, we specialise in helping homeowners:
  • Study the nuanced differences between A&A and Reconstruction
  • Weigh the pros and cons of each approach based on design vision and cost strategy
  • Ensure regulatory compliance while achieving your desired transformation

With our design-led expertise and deep understanding of construction intricacies, we help you make informed decisions that align with both your aesthetic goals and financial considerations.

How to Decide: A&A or Reconstruction?

new construction/
rebuild

Embark on new construction with us, where possibilities are endless on a clean slate. 

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reconstruction

Explore our reconstruction services, offering the opportunity to transform your home versus rebuilding. 

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other landed home services in singapore

Yes, depending on the scope of work, A&A projects may require approvals from the Urban Redevelopment Authority (URA) and the Building and Construction Authority (BCA).

Minor A&A works (such as internal renovations) may only require MCST or local council approvals.
Significant modifications (e.g., extensions, facade alterations) may need formal submissions to regulatory bodies.
At Haus Atelier, we assist in navigating the submission process to ensure compliance.
Generally, A&A is more cost-effective than Reconstruction since it preserves much of the existing structure, reducing demolition and rebuilding costs. However, the savings depend on factors like:
  • The extent of changes required
  •  The complexity of renovations
  • Material choices and customization

At Haus Atelier, we help homeowners strategize their renovation plans to achieve the best balance between design, cost, and functionality.
A&A projects involve upgrading and modifying a home while keeping its original structural framework intact. As long as structural and facade changes do not exceed 50%, the project remains classified as A&A. If modifications go beyond this threshold, the project will be considered Reconstruction, requiring more extensive regulatory approvals.
A&A projects can significantly enhance a home without requiring a full rebuild. Common A&A works include:
  • Adding a home lift
  • Reconfiguring the staircase
  • Modifying the roof structure
  • Building a swimming pool
  • Expanding rooms or minor extensions

However, a combination of major changes (e.g., adding a new floor + modifying the facade) may shift the project into Reconstruction territory.
A&A projects typically take between 8 - 18 months, depending on:

  • The extent of renovations
  • Approval processes from authorities
  • Material selection and construction complexity

Projects with fewer structural modifications tend to have faster turnaround times compared to full-scale renovations or reconstructions.

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