How to Read and Interpret Any HDB Floor Plan in 5 Minutes

It's all about understanding the symbols.

Floor plans are scaled 2D diagrams that are meant to provide clarity on the overall structure of a house or building unit.

And while they’re relatively easy to understand for a professional or seasoned homeowner, the same can’t be said for anyone who’s seeing one for the first time. (Here’s looking at you, newbie BTO flat applicants.)

To save you the headache of figuring out what each symbol represents, here’s a detailed, novice-friendly breakdown of every icon that you’ll see on a modern-day floor plan from HDB and/or your interior designer!

Walls (represented as filled/unfilled lines on floor plans)

To an untrained eye, almost every wall looks the same: solid structures that act as separators between rooms or the outside.

However, knowing how to read a floor plan will tell you more about these partitions – which will certainly come in handy if you’re planning to demolish a wall (or two) to create an open-concept layout for your home.

1. Structural walls/columns (i.e., cannot be demolished)

Represented by bold lines, structural walls/columns are the foundations of HDB flats and hence cannot be demolished away. However, there are ways to cover up these building elements, either by concealing them behind a false wall or building cabinetry around them.

Similarly, the walls around a household shelter, which also can’t be hacked, are likewise depicted as bold lines on floor plans.

Regular walls (i.e., can be demolished)

Partition or non-structural walls are shown on floor plans as a pair of thin lines with a gap between them.

These are the walls between rooms that you’re legally allowed to demolish (with HDB’s permission), if say, you’re interested in creating an open-concept layout for your home or replacing your study room’s partitions with glass partitions.

3. Gable-end walls (cannot be demolished too)

Depending on the position of your HDB unit, you may or may not have gable-end walls in your home (only end point units have them), and they typically show up on floor plans as a pair of thin lines with another line or slit between them.

These structures are essentially part-internal and part-external because they are the only barriers separating the inside of your home/bedroom from the outside. For this reason, gable-end walls cannot be demolished.

4. Wall/floor length (measured by mm)

Though they aren’t structural elements or home features, the numbers indicated on a floor plan are no less important because they indicate the internal dimensions of your flat (in millimetres), such as floor length or wall length.

Taking note of these figures is important as they’ll inform some of your renovation decisions, such as the amount of vinyl you need to cover your floors or how long you might want a new kitchen island to be.

Doors (indicated as curves on floor plans)

Just like walls, doors have their own unique symbols indicating key details such as opening direction and radius. Here are some examples:

1. Swing doors

The bread-and-butter fixtures of indoor privacy, swing doors are represented by a quarter circle, which in turn indicates their swing radius.

Taking note of this detail in the early stages of your renovation can come in helpful later when you’re planning the size of built-ins that are close to doorways, as it’ll save you from dealing with tight passageways and/or obstructions.

2. Folding doors

Folding doors are commonly found outside bathrooms, service yards or other tight areas where they provide privacy without taking up too much space.

You can identify a folding door on a floor plan from its triangular icon, which also indicates which way it slides to open.

3. Doors that aren’t provided by HDB

Although they’re also shown as a quarter circle just like swing doors, these entryways don’t have doors installed in them unless you’ve signed up for the Optional Component Scheme (OCS).

A dotted or dashed arc on a floor plan not only indicates the absence of a door but also an optimum opening radius if you were to install one with a hinged opening mechanism. So take note, especially if you’re a (to-be) owner of a brand-new, unrenovated BTO flat.

4. Doors that are provided by HDB

Conversely, an arc (for swing doors) or wedge (for folding doors) with solid outlines is indicative of doors that come with a new BTO flat (i.e., provided by HDB).

Examples of doors that are usually provided in BTO flats include service yard bi-fold doors as well as household shelter doors, which are made of steel.

Windows

Though not all of these windows will offer a panoramic view of your neighbourhood, it’s still important to take note of where they’re positioned in your BTO/HDB flat – if not for space-planning reasons then for ones relating to ventilation.

1. Sliding windows

Sliding windows show up on floor plans as thin, hollow lines that can be quite hard to notice, so keep your eyes peeled.

Knowing where they’re positioned can prove to be helpful when looking for the optimum layout for your living area, especially if you’d like a seating/TV watching spot that’s as airy as possible.

2. Casement windows

Compared to their sliding counterparts, casement windows are a much more common sight in modern-day BTO/HDB flats as default fixtures. And just like swing doors, they appear on floor plans as one or more quarter circles that indicate opening radius and direction.

3. Top hung windows

In most BTO/HDB flats, top-hung windows are installed to provide bathroom ventilation. You can identify these openings on floor plans by tiny rectangles with a dotted line in the middle. The same applies to louvered windows as well, which are more frequently found in older HDB flat bathrooms.

Other symbols that you might find on an HDB floor plan

1. Staircases

If you’re lucky enough to live in an HDB maisonette with stairways, you’ll find them indicated in your floor plan as a series of lined rectangles. You’ll also see an arrow indicating the way up, as well as the number of risers (the vertical part of a stair, usually abbreviated as ‘R’ on floor plans) that the entire staircase has.

2. 50/100mm level drop

A number – usually 50 or 100 – accompanied by the word ‘drop’ on a floor plan indicates in millimetres the difference in height between one part of your HDB flat to another. (E.g., between the front entrance and living area OR kitchen and bathroom.)

This Is a useful detail to take note as it’ll help you identify the threshold between different parts of your home, as well as inform you about how much material you may need if you wish to level the floors of two areas with varying heights.

3. Laundry rack

Last but not least are the trio of black lines on a floor plan that indicate where your BTO/HDB flat’s laundry rack is located.

Though these fixtures have been installed in modern-day HDB flats by default since 2018, you may find them missing on the floor plans of older units – which means you’ll probably have to shop for your own!

This article was originally published on 3 April 2017 and last updated on 25 April 2023.

Your dream home is just a few clicks away!

Simply tell us your renovation requirements and we can get you personalised renovation quotes from five local interior design firms for free.

Also, when you engage an interior firm through our free recommendation service, you’ll get to enjoy perks under the Qanvast Trust Programme – including but not limited to, the $50,000 Qanvast Guarantee, refundable deposits, and extended warranties with selected firms!

Follow us on Telegram to get the latest reno updates! 🙌

Renovate with assurance, only on Qanvast. Find and meet interior designers verified by homeowners, with no hidden costs and no commissions involved. Find an ID