How to Maximise GFA When Rebuilding a Landed Home

How to Maximise GFA When Rebuilding a Landed Home in Singapore

For Singapore homeowners, whether living in a terrace at Telok Kurau, a semi-D in Bishan Park, or a bungalow in Bukit Timah, maximising GFA (Gross Floor Area) is one of the smartest ways to increase living space and property value.

Many older homes in estates like Sunset Way, Kew Drive, Seletar Hills, and Braddell Heights were built decades ago, with layouts that no longer reflect modern living needs. When rebuilding, homeowners often want:

• a larger master suite

• more bedrooms

• helper’s room

• study room

• bigger kitchen

• entertainment room

• attic or basement

This article explains how to maximise your GFA legally and efficiently under URA Envelope Control Guidelines, with practical examples across various Singapore districts.

1. Understanding URA Envelope Control (Simple Explanation)

Most landed homes in Singapore are governed by URA’s Envelope Control guidelines, which define:

• how high you can build

• how far you must set back from boundaries

• roof slope and attic rules

• GFA calculation limits

Depending on district zoning (2-storey, 2.5-storey, 3-storey), your maximum potential varies.

Examples:

• Many houses in Siglap, Opera Estate, Lucky Heights are in 3-storey zones → higher GFA potential.

• Parts of Bukit Timah, Dunearn Road, and Chancery Lane fall under 2-storey mixed landed → more conservative height limits.

• Newer clusters like Lentor, due to MRT-driven urban planning, allow more innovative roof forms within envelope control.

2. Build Upwards: Attic Works (Most Common GFA Maximisation Method)

Adding an attic is one of the easiest ways to significantly increase usable floor area.

Terrace and semi-D homeowners in:

• Serangoon Garden (Burghley, Cowdray)

• Thomson Ridge / Windsor Park

• Luxus Hill / Yio Chu Kang

• Frankel / Siglap / Telok Kurau

regularly add attics because land plots are narrow but have vertical allowance.

URA Attic Requirements

• Attic must fit within the sloping building envelope

• Internal height has limits (floor-to-roof profile)

• No full 3rd storey if the zoning is 2.5-storey

What homeowners usually use attics for:

• Additional bedroom

• Entertainment room

• Home office

• Kids’ playroom

• Gym

3. Maximise Rear Extensions (Deep Plots Benefit the Most)

Many landed houses built in the 80s and 90s have large backyards that can be extended into under a rebuild.

Key areas where rear extensions are common:

• Jalan Khairuddin / Kew Estate

• Sunset Way Estate

• East Coast Terrace

• Springleaf (near new MRT)

• Pasir Panjang landed pockets

Rear extensions allow:

• Larger wet kitchen

• Adding helper’s suite

• Expanding dining area

• Laundry/drying yard

In deep plots like those along Telok Kurau, the rear extension can easily add 200–400 sqft of GFA.

4. Shift Staircase or Reconfigure Circulation

Many older houses in:

• Clementi Park landed zone

• Bishan’s Braddell Heights Estate

• Seletar Hills

have awkward staircase placements that waste usable GFA.

By shifting the staircase:

• hallways become more efficient

• rooms enlarge

• bedrooms become rectangular instead of irregular-shaped

• ventilation improves

This is particularly impactful for intermediate terraces.

5. Build a Basement (High-Value But High-Cost GFA Increase)

Basements significantly increase usable area without changing envelope control.

More common in:

• Bukit Timah bungalows

• Binjai Park

• Holland / Farrer landed belts

• Caldecott Hill

• Lentor / Springleaf (because of new TEL MRT making area more desirable)

Uses of basements:

• entertainment room

• wine cellar

• home theatre

• gym

• maid’s suite

• utility room

Basements add massive GFA, but require:

• retaining walls

• waterproofing

• soil investigation

• drainage planning

6. Use the Roof Space Smartly: Roof Terrace or Attic Balcony

Homes in:

• Lucky Heights

• Upper East Coast

• Lentor private estate

• Sunset Way

often have roof terraces designed into the rebuild.
These do not always add GFA, but create usable outdoor space which increases liveable feel.

7. Reconfigure Front Car Porch Width (Where Allowed)

Some homeowners maximise GFA by adjusting the car porch depth, if setback rules allow.

This frees up internal GFA by shifting internal walls further out.

Applies well to:

• Braddell Heights

• Serangoon Garden

• East Coast Terrace lanes

• Thomson Ridge

Always subject to URA setback restrictions.

8. Combine Rooms for Multi-Functional Spaces

Many older houses have too many small rooms.

By combining, for example:

• small room + corridor = large bedroom

• useless balcony + room = bigger living

• old void area + room = new study

You gain effective GFA without expanding footprint.

Popular among condo upgraders accustomed to open-concept spaces.

9. Strategic Window Placement to Unlock More Usable Space

This doesn’t directly increase GFA, but unlocks usable area by improving light and ventilation, important in narrow terrace estates like:

• Telok Kurau

• Opera Estate

• Jalan Daud / Jalan Waringin belt

• Kovan Road lanes

Light wells, skylights, and side windows (if corner unit) can make hidden corners more functional.

10. Knowing What Doesn’t Count as GFA

Some features fall under “exempted areas” and don’t count as GFA, yet improve liveable value enormously:

• Car porches

• Roof terraces

• Air-conditioning ledges

• Certain mezzanine spaces (with height control)

• Balconies (controlled depending on zone)

This allows homeowners to enlarge liveable functionality without breaching GFA caps.

Master Plan & MRT Considerations

Rebuilds in MRT growth areas often benefit more from maximised GFA because future demand increases property value.

Examples:

TEL (Thomson-East Coast Line)

• Springleaf

• Lentor

• Upper Thomson

• Marine Parade

• Siglap

• Bayshore (future)

These areas are experiencing redevelopment momentum; maximised GFA amplifies long-term value.

Beauty World Integrated Transport Hub (upcoming)

Landed homes near:

• Jalan Jurong Kechil

• Bukit Timah Link

• Lorong Kismis

see rising demand.

Cross Island Line (CRL future)

• Serangoon North

• Ang Mo Kio

• Hougang

Older terraces here are being rebuilt more frequently as accessibility improves.

Useful Links

For homeowners planning to rebuild and want a clear view of costs:
🔗 Cost to Rebuild a Landed House in Singapore (2026 Guide)

If you're deciding whether A&A is enough before adding GFA:
🔗 Rebuild vs A&A: Which Option Is Better for Your Landed Home?

If you want to understand the full rebuild timeline before expanding GFA:
🔗 How Long Does a Landed House Rebuild Take in Singapore?

For a complete process walkthrough before planning any GFA increase:
🔗 Step-by-Step Guide to Rebuilding a Landed Home