What is Duplex House - All You Need to Know

Duplex house is a residential dwelling with two living units attached to each other. The duplex house plan is such that the attachment of two units can be either next to each other, like in condominiums and townhouses, or it can be one above the other way.

In most cases, the duplex house design refers to one unit above another. However, with innovations and developments in the architectural trends, both duplex house designs and duplex house plans have changed according to modern times.

What is a duplex House?

A duplex house is a type of house that has two residential units stacked or joined with one another. It can be in a vertical format or a side-by-side style. Generally, a Duplex house consists of residential units spread over two floors with a kitchen and a common area. The duplex house has two floors, and these floors are connected by a staircase.

Here, two residential units can also share a common wall, but they are sold independently. Duplex houses with two floors are generally sold collectively. A duplex house is often confused with a twin home. A twin home is half homes in their own separate lot, whereas a duplex is a property on a single plot.

If modern duplex house design in India is considered, a duplex house plan follows a pattern where a kitchen, hall and a bedroom is on the ground floor, and one/two bedrooms are on the upper floor. A duplex house must consist of two floors only. If a residential house has three floors, then it would be termed as a triplex. If it has multiple floors, then it would be categorised as a Multiplex.

In duplex house trends in western countries are observed, it is seen that a duplex house is rented to more than one family. It is done to get better rental returns out of a single duplex house. However, in such cases, the entrance for the upper portion is separate.

Types of Duplex House

Duplex house design and duplex house plan differ from country to country. Broadly, the duplex house can be classified into the following types-

Ground Duplex House

A duplex house, which is built on the ground floor of an apartment, is known as a ground Duplex. In this type, the lower floor of the duplex faces the garden, while the upper portion houses a kitchen and a living room.

Ground Duplex House is generally preferred by homebuyers who prefer to have an open garden attached, which can serve their pets as well.

Standard Duplex House (Most common)

This type of Duplex house is the most readily found duplex house design. In this, two floors are built vertically, one over the other. In this modern duplex house design, the lower floor generally consists of a kitchen and a living room, while the upper floor houses two bedrooms or a single bedroom with a children's room.

Low-rise Duplex

This state-of-the-art modern duplex house design includes spacious balconies on the upper floor. The area of this duplex house is generally smaller than other duplex house designs. This type of modern duplex house design is a challenge for the architects, and they have to make sure of the optimal utilisation of the space available.

Duplex House: Different meanings in different countries

A duplex house bears different meanings in different parts of the world. While, in general, a duplex refers to a house with two entities, it is denoted in a slightly different way at different places. For instance, in Chicago (USA), a duplex house is a single residential unit spread over two floors and connected by a staircase internally.

If we take the case of the United Kingdom, a duplex house is a flat or an apartment on two floors. It is also referred to as a ‘Maisonette’. Whereas in Australia, a duplex house is generally a residential building with two homes, and they share a common wall. These two parts can be called mirror images of each other.

What are the advantages of a duplex house?

Duplex houses offer a series of advantages in terms of privacy, affordability, and accommodative quotient. Here are a few advantages of a duplex house.

1. Privacy-
A duplex house is ideal for joint families where everyone wants to lie under one roof but wants to have his/her own privacy. The space can be utilised to ensure optimum space for every inhabitant.

2. Affordability-
It is a fact that duplex seems to be a costly proposition; it is not that expensive. In comparison to the flats of similar price range and area, they are only a bit on the higher side. If you can manage the finances a little, a duplex can be afforded easily

3. Accommodative-
After all, a duplex has the advantage of having two units inside a single home. Therefore, in terms of housing capacity, a duplex house can easily accommodate two families independently.

4. Sourceof Additional Income-
As a duplex house has an additional unit for housing a family, it can easily be rented to earn additional income. However, to rent a part of a duplex house, it is better to have a separate entrance.

5. Additional Space for Home Office-
If you want to run a business from home, a duplex can be an ideal solution for that. You can set up a dedicated office or meeting room on the ground or upper floor and work from home without leasing or renting an expensive office.

Disadvantages of a Duplex House

There are a range of disadvantages associated with owning a duplex.

• Usually, a duplex comes with a common wall. This can turn out to be a cause of concern for the inhabitants as noise may transmit to the other part of the duplex. A similar issue can crop up in a traditional duplex where families living on either floor might get disturbed by the activities of others.
• If the duplex is connected by an internal staircase, it might be very difficult to house a tenant as they will use the internal area for commuting. An additional part of a duplex house can be rented easily only if it has a separate entrance.
• Duplex houses are common in areas where there is less congestion and ample land bank. Finding a spacious duplex within city limits can be a task and might create a hole in your pocket if you find one.
• A duplex house is generally privately owned. This brings a load of maintenance and gardening to the landlord. It might get difficult to manage a large duplex on your own.

The construction cost of a duplex house in India

The construction cost of a duplex house or any residential dwelling, for that matter, depends upon a host of factors like location, material used, area of the land and furnishing material cost, among others. In general, a duplex construction will cost Rs 1200-1500 per sq ft in India.

The construction cost of a duplex house depends upon the following factors-

• Type of construction,


• Choice of finishes,


• total area to be constructed in one go,


• Time consumed


• Availability of finances,


• Experience and expertise of the contractor


• Availability of construction machinery


• Availability of construction material required


• Prices of steel, cement, bricks, wood, labour


• Distance of construction site from the market etc.


• Comparison of a duplex house with other house formats

Here is a comparison of a duplex house with that of other common houses-

Difference between Duplex house and penthouse

Penthouses are a peculiar kind of residential dwellings that are located at the top of a multi-story building or apartment. At the same time, a duplex house is a double story house that can be present on any floor of an apartment or can be there as an independent unit. Penthouses are generally expensive, as they offer a grand view and are generally the sole unit on that floor.

Difference between Duplex house and independent house

An independent house is a broad classification covering even a duplex. It is used interchangeably to refer to large houses, villas, duplex etc. An independent house can be a duplex, a large bungalow, farmhouse, but the duplex essentially has two floors.

Difference between Duplex and townhouse

A duplex is a two-floor structure (either side-by-side or vertical) that is generally privately owned. However, a townhouse houses several dwellings with shared walls, and it has multiple owners.

Difference between Duplex house and a two-storey house

A duplex house essentially means a two-storeyed structure, but all two-storeyed buildings might not be categorised as duplex houses. In duplex house design, both the floors are internally connected through stairs; a two-storeyed building might be independent and might or might not be internally connected like a duplex.

Difference between Duplex house and villa

The term villa is generally reserved for a large house, and it is usually larger than a duplex. It is usually dearer than a duplex too. The villa as a house type has been around for centuries, but duplex is a relatively new concept. Villas in a gated community are offered amenities such as a gymnasium, community centre and security services, among others. With a duplex, these services are generally not present.

Conclusively, a duplex house is essentially a two-storeyed dwelling with a living room on one floor and bedrooms and a children room on the other. The modern duplex house design may offer different layouts for interiors and space optimisation as per the latest trends.