HDB Door and Gate Sizes in Singapore – Simple Guide for Homeowners
Introduction: Why Door and Gate Sizes Matter
Moving into a new unit or upgrading your resale HDB unit? One of the most important things to check is your gate and door size. Choosing the wrong size can cause installation issues and unnecessary costs.
This guide will help you understand standard HDB door sizes, gate sizes and when you may need larger or custom doors, especially for unique flat layouts.
1. HDB Main Gate Size (3x7 ft and 4x7 ft)
Just like doors, HDB gates also come in standard sizes—3×7 feet and 4×7 feet. If your home has a 4×7 feet main door, your gate should match in size for proper alignment and fit.
These larger 4×7 gates are commonly seen in flats with double-door entrances.
2. Standard HDB Main Door Size (3x7 ft and 4x7 ft)
Most HDB units use a 3 x 7 feet door (approx. 915mm x 2135mm). This is the standard size for main doors in both new and older flats.
However, some units —may use a larger 4 x 7 feet door. These are either wide single door or double-leaf doors.
Thickness usually ranges from 40mm to 45mm for standard fire-rated main doors.
3. Why Door Thickness Matters for Digital Lock Installation
Most HDB doors are 35mm thick, where as Fire-rated doors would be 45mm thick or greater.
Why does this matter? Because certain digital locks need a minimum thickness to install properly. Always check your lock specifications before buying a new door.
4. Standard Bedroom Door Size
Bedroom doors in HDB flats are usually smaller and simpler than main doors.
• Size: 3 x 7 feet (915mm x 2135mm)
• Thickness: 36 mm ± 2 mm
This size is enough for privacy and comfort without taking up too much space.
5. HDB Toilet Door Size and Thickness
Toilet or bathroom doors are typically 3 x 7 feet (915mm x 2135mm) and lighter than main doors, they generally follow a standard height and are designed to fit tight spaces.
• Thickness: Around 35 mm
These doors are usually made from moisture-resistant materials such as aluminium making them suitable for humid environments like bathrooms.
6. When You Need a Custom Door or Gate?
You may need a custom-size door or gate if:
• Your door opening is larger than 3 feet wide
• You have a double-leaf (split) door
• Your unit is a corner or jumbo unit
• You want a unique design or material not sold as standard
Custom orders are common for 4×7 ft doors and gates, so be sure to measure carefully and consult the supplier.
7. What to Check Before You Buy
To avoid sizing or fitting issues, always confirm the following:
• Width and height of your existing door or gate
• Thickness of the door
• Fire-rating requirement
• Digital lock compatibility
Bringing these details to a supplier like us makes the purchase and installation process much smoother.
8. How to Measure Your Door Correctly
Steps for Accurate Measurement:
- Width: Measure the opening of the door frame from left to right.
- Height: Measure from the floor up to the underside of the top frame.
- Thickness: Measure the edge of the door to ensure compatibility with your chosen lockset or design.
Note: Always record measurements in millimeters (mm) for the best accuracy.
Where to buy a New Door or Gate?
Explore SmartKakis’ collection of HDB-approved doors and gates, available in 3×7 ft and 4×7 ft sizes—perfect for both BTO and resale homes. From stylish main doors to secure, digital-lock-compatible gates, we’ve got options that fit every home.
🔍 Browse our door and gate catalogue to discover the latest designs and enjoy hassle-free installation when you shop with us.