How Much Does A&A Work Cost in Singapore? (2026 Estimates)

How Much Does A&A Work Cost in Singapore? (2025 Estimates)

A&A (Additions & Alterations) is one of the most popular upgrade methods for older landed homes in Singapore. Whether you own a terrace in Kovan, a semi-D in Serangoon Gardens, or a bungalow in Sunset Way, A&A lets you enlarge, modernise, and enhance your home without the cost or disruption of a full rebuild.

But how much should you realistically budget for A&A works in 2025?
What affects the price?
Which hidden costs do most homeowners overlook?

This detailed guide covers real-world numbers, variations by home type, district-based differences, and the factors that commonly lead to cost escalations.

1. Average A&A Cost in Singapore (2025)

Typical Price Range: $200,000 – $600,000+

The actual figure depends heavily on:

• home type

• house age

• scope of extensions

• structural changes

• façade redesign

• electrical & plumbing upgrades

• whether the house is occupied

• district access conditions

Below is a realistic breakdown.

2. A&A Cost by Property Type

A. Inter-Terrace Houses

Common in:

• Opera Estate

• Telok Kurau

• Serangoon North

• Kovan

• Upper Serangoon Road

• Joo Chiat / Mountbatten (non-conservation pockets)

Typical Range: $200,000 – $450,000

Why inter-terraces cost less:

• smaller floor area

• simpler structural profile

• limited extension opportunities

• typically 3 bedrooms + attic

When costs exceed $400k:

• adding new bathrooms

• major kitchen expansion

• full façade redesign

• rebuilding staircase

• adding skylights and ventilation shafts

• upgrading entire M&E system

Homes in deeper plots (e.g., Telok Kurau lanes) require more extensive drainage and waterproofing → higher A&A cost.

B. Corner Terrace & Semi-Detached Houses

Common in:

• Serangoon Gardens

• Thomson Ridge

• Seletar Hills

• Sunset Way

• Bedok South / Kew Drive

• Lentor private estate

Typical Range: $300,000 – $600,000

Why semi-Ds cost more:

• larger footprint

• more façade to refurbish

• more bathrooms

• roof redesign is more complex

• bigger kitchen & dining zones

• higher neighbour protection costs

Corner terraces often benefit from side extensions, but these require structural reinforcements and boundary wall upgrades, increasing A&A cost.

C. Detached Houses / Bungalows

Common in:

• Bukit Timah (D10/11)

• Holland

• Brizay Park

• Sentosa Cove

• Caldecott Hill

• Windsor Park

Typical Range: $400,000 – $900,000+

Higher-end bungalows (e.g., Watten Estate, Oei Tiong Ham Park) have more premium expectations, and owners often choose:

• façade overhauls

• new roofing structure

• multiple new bathrooms

• dry + wet kitchens

• large glass openings

• home lifts

These significantly increase A&A budgets.

3. Breakdown of A&A Cost Components

A&A costs vary widely because they contain several “sub-projects.”
Here's an accurate breakdown based on Singapore market rates.

A. Extensions & Structural Alterations ($40,000 – $200,000)

Rear extension

Most common in:

• Opera Estate

• Serangoon Gardens

• Thomson

• Telok Kurau

• Hougang terraces

Typical cost: $50,000 – $120,000, depending on size.

Side extension (corner terraces / semi-Ds)

Common in:

• Thomson Ridge

• Seletar Hills

• Sentosa landed cluster

• Sunset Way

Typical cost: $30,000 – $100,000.

Adding bathrooms or enlarging kitchen

Costs rise due to plumbing works.
Typical cost: $25,000 – $60,000.

Façade redesign

From simple modernisation → full architectural change.
Cost: $20,000 – $100,000+.

B. Roofing Works ($15,000 – $80,000)

RC roof reinforcement

Common in older terraces, especially Telok Kurau and parts of Frankel.

New metal roof

Cost: $30,000 – $60,000 depending on complexity.

Partial roof redesign

Cost: $20,000 – $45,000.

C. M&E Upgrades ($20,000 – $120,000)

Older systems in landed homes often require full upgrades:

• re-piping

• re-wiring

• new DB box

• new aircon trunking

• ventilation shafts

• additional circuits

Higher-end areas (e.g., Bukit Timah, Holland) may spend more due to premium systems.

D. Windows, Doors & Glazing ($15,000 – $80,000)

Modern landed homeowners in 2025 prefer:

• full-height sliding systems

• low-E glass

• aluminium frames

• noise reduction laminated glass

Costs vary heavily depending on brand and size of openings.

Homes near MRT tracks or main roads (e.g., Upper Serangoon, Adam Road, Pasir Panjang) benefit greatly from acoustic glazing.

E. Carpentry & Interiors ($30,000 – $120,000)

Includes:

• kitchen cabinets

• built-in wardrobes

• storage systems

• bathroom vanities

Condos typically have built-in storage, but older landed homes do not, hence condo upgraders often invest heavily here.

F. Waterproofing & Drainage Improvements ($10,000 – $60,000)

Older estates like:

• Frankel

• Opera Estate

• Pasir Panjang

• Kembangan

• Braddell Heights

often require updated drainage and waterproofing due to age + terrain.

4. Factors That Increase A&A Costs (Often Unexpected)

1. House Age & Structural Condition

Older homes (40–50 years old) often reveal issues like:

• spalling concrete

• termite damage

• weak beams

• outdated sewer lines

• foundation settlement

These raise costs significantly.

2. District Location & Access Difficulty

Some neighbourhoods have narrow or sloped roads that make deliveries and scaffolding difficult:

• Joo Chiat

• Opera Estate

• Thomson Ridge

• Pasir Panjang slopes

• Sunset Way cul-de-sacs

Restricted access = higher labour and machinery cost.

3. Extent of M&E Overhaul

Homes near new MRT lines (e.g., Lentor, Upper Thomson, Marine Parade) often see new buyers expecting modern M&E standards.

4. Home Still Occupied During A&A

A&A while living in the house requires:

• dust protection

• sequencing

• phased work

• safety barriers

→ All these increase cost.

5. Premium Material Choices

Especially for owners in:

• Bukit Timah

• Holland

• Sentosa Cove

• Nassim fringe landed areas

Materials significantly affect budget.

5. Hidden Costs Homeowners Commonly Forget

Neighbour Protection Works (NPW)

Especially for inter-terraces in:

• Opera Estate

• Serangoon North

• Thomson Garden Estate

Cost: $3,000 – $30,000.

Authority Submission Fees

PE endorsements, BCA submissions, and SCDF checks can add $5,000 – $15,000.

Drainage Realignment

Properties in low-lying areas (e.g., Pasir Ris, Bedok South) occasionally need drainage work.

Temporary Relocation Costs

Many homeowners underestimate the logistics of staying elsewhere during A&A.

6. Are A&A Costs Worth It Compared to Rebuilding?

A&A makes sense when:

• structure is still strong

• GFA potential is limited

• budget is constrained

• you want a faster turnaround

• you don’t intend to sell immediately

Rebuilding makes sense when:

• structure is old

• GFA potential is huge

• long-term resale is priority

• layout is fundamentally poor

Homes in Serangoon Gardens, Thomson, Kew Drive, Frankel, and Sunset Way often benefit more from A&A if the structural bones are still solid.

7. How to Budget Properly for A&A

1. Include at least 10–15% buffer

Unforeseen conditions are common in older houses.

2. Prioritise structural & M&E first

A nicely renovated home with old wiring = future regrets.

3. Understand which upgrades offer highest value

• kitchen expansion

• new bathrooms

• ventilation/light improvements

• façade modernisation

These provide strong ROI.

Useful Links

For homeowners wanting to engage a specialist for A&A works:
🔗 A&A Contractor Singapore

If you're choosing between A&A or full rebuild based on cost:
🔗 Landed House Rebuild Contractor Singapore

To understand the regulatory limits & what’s allowed:
🔗 A&A Guidelines for Singapore Landed Homes, What BCA Allows & Doesn’t Allow

To learn how to expand your home without triggering a rebuild:
🔗 How to Expand Your Landed Home Legally Using A&A Works

For hidden cost awareness during the planning stage:
🔗 Hidden Costs Homeowners Overlook When Rebuilding

To explore how much space you can unlock with A&A:
🔗 Tips to Maximise Floor Area Without Full Rebuild