Apartment types: studio, duplex, penthouse and builder floor

1.9.1 What do the different apartment types mean?

Apartment names describe several different things: room layout, number of levels, position in the building or the way a home is marketed. Cambridge Dictionary defines a studio as one main room with a bathroom and kitchen area, a duplex apartment as living accommodation on two floors, and a penthouse as accommodation at the top of a building. A single home can therefore be both a duplex and a penthouse. BHK answers a different question: how many bedrooms, with a hall and kitchen. The BHK meaning guide explains that label. Builder floor and gated community are treated here as market usage, so ask the seller what each means for this project. Sachi’s reading: begin with the dimensioned plan, then use the name as a short description of the home you have already checked.

Label	Feature it describes	What to verify
Studio	One main living and sleeping room	Separate bathroom, kitchen arrangement and storage
Duplex apartment	Living space on two floors	Both approved levels, internal connection and unit identity
Penthouse	Position at the top of a building	Exact floor, any terrace rights and roof services
Builder floor	Market description of a floor sold as a home	Unit boundaries, land share and shared facilities
Gated community	Market description of controlled entry and shared facilities	Actual access arrangements, promised amenities and upkeep

The first three descriptions use Cambridge Dictionary. The last two describe market usage rather than a legal category established by the sources for this guide.

1.9.2 How is a studio different from a 1BHK?

A studio combines the main living and sleeping functions in one room, while a 1BHK has a separate bedroom. That distinction comes from the studio definition in Cambridge Dictionary and from the BHK guide. It says nothing about which home has more usable floor space. Sachi’s reading: draw your bed, sofa, work desk and dining arrangement on each dimensioned plan. Check whether someone can cook while another person sleeps, where clothes will dry and whether there is space to open cupboard doors. Ask whether the kitchen is a separate enclosure or an open area within the main room. Count the windows and inspect the bathroom access. A studio may suit a household that wants one open space; a separate bedroom may suit a household that needs different sleep and work schedules. Choose from the plan and your routines.

For a new purchase, ask the builder to identify the unit’s sanctioned use and the same unit in the agreement. A brochure calling accommodation a studio does not by itself tell you whether the sanctioned use is residential.

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1.9.3 What should you check in a duplex apartment?

A duplex apartment has living accommodation on two floors, but the word needs context. Cambridge Dictionary also gives an American meaning of a house containing two separate apartments, each with its own entrance. For a Bangalore purchase, ask the builder to show exactly what it is offering on the approved plan. Sachi’s reading: confirm whether you are buying one connected apartment, two separately identified units or an independent house. Inspect both levels and the internal stair. Put everyday activities on the plan: sleeping, bathing, cooking, working and storing luggage. Decide whether a family member could use the home without climbing the stairs each day. Measure the landing and the route for moving furniture. Check where the upper-level toilets and service shafts sit. The name alone cannot resolve these questions, and it should never substitute for the plan attached to your agreement.

The floor plan guide explains how to read dimensions. Ask for a written area schedule for both levels and any void or double-height space, so that you understand how the builder arrived at its quoted area.

1.9.4 What makes a penthouse different from another top-floor flat?

A penthouse is an apartment at the top of a building, according to Cambridge Dictionary. The dictionary definition does not give a minimum floor area, a fixed number of bedrooms or a required private pool. A builder may market a particular top-floor home with extra outdoor space or specifications, but those are separate promises to check. Sachi’s reading: compare it with another unit in the same project using the full cost, carpet area, layout and written list of extras. Ask which spaces are inside the apartment and which are outside it. Walk the route to roof equipment and ask whether staff will need access near your home. Inspect the proposed shade, drainage and waterproofing arrangements for any outdoor space. Request the upkeep responsibilities in writing. Decide whether the specific extras are useful to your household before you pay a premium for the label.

A duplex penthouse combines the two descriptions: it sits at the top and has rooms on two floors. A top-floor location alone does not prove that every part of the roof is included in the sale.

1.9.5 Does a penthouse come with a private terrace?

A penthouse name does not establish terrace rights. The RERA Act distinguishes an exclusive open terrace associated with an apartment from common terraces. Section 2(k) excludes the exclusive open terrace from carpet area, while section 4(2)(h) requires that area to be disclosed separately. Section 2(n) includes common terraces among common areas. Sachi’s reading: ask your lawyer to match the specific terrace shown on the approved plan with the agreement, conveyance documents and any applicable registered Declaration. Have the documents specify the area, permitted access and maintenance duties. Ask how staff will reach tanks or other shared services. Check whether you are being promised exclusive use or some other right, and have that wording explained before you sign. A salesperson’s statement that the roof is yours leaves these practical and legal questions unanswered.

Use the carpet area guide to keep indoor and outdoor areas separate when comparing price. Do not treat exclusive use as permission to build an extra room; ask the planning authority and your lawyer about any proposed alteration.

Section 2(k) also excludes exclusive balcony and verandah area from carpet area, using the same logic as the exclusive terrace. Ask the builder to show these three areas, carpet, exclusive balcony or verandah, and exclusive terrace, as separate figures in the agreement, not as one combined number.

1.9.6 What does builder floor mean for ownership and upkeep?

Builder floor is used in property marketing for a floor offered as a separate home within a building. This guide treats it as market usage, because the cited sources do not establish a single legal meaning for that label. Sachi’s reading: ask what is being conveyed to you, including the apartment boundaries, land interest and rights over stairs, parking and the roof. Check the sanctioned number of homes and floors against what you can see on site. Identify who owns the other floors and how common repairs will be decided and paid for. Ask about separate meters, water storage and access to shared equipment. Verify the legal documents and applicable registration or approval requirements for that development. The small number of homes in a building does not answer those questions, and the term builder floor cannot replace a title review.

The undivided share of land guide explains the land interest to check in an apartment purchase. Ask for the exact share and its basis rather than assuming that owning a whole floor means owning a marked portion of the plot.

A small builder-floor building can fall outside RERA registration. Section 3(2)(a) of the RERA Act says no registration is required where the land proposed for development does not exceed 500 sq m, or the number of apartments does not exceed 8, inclusive of all phases. Sachi’s reading: if a builder-floor project is this small, ask directly whether it is registered, and if not, ask why not. Request the sanctioned plan from the local planning authority instead, since an unregistered project still needs that approval. Treat the absence of a RERA number as a fact to verify, not as proof of a problem by itself.

1.9.7 What do gated community and semi-furnished actually promise?

Gated community describes access and shared facilities in market usage, while furnished, semi-furnished and unfurnished describe what the seller says will be supplied inside the home. These labels do not settle a layout, an ownership right or a complete inventory. This guide uses them as descriptions to clarify with the seller, rather than a fixed legal specification. Sachi’s reading: for a gated development, ask who controls entry, who uses each amenity and what upkeep you will pay. For furnishing, obtain an itemised annexure with quantities, specifications and condition. Name the cupboards, kitchen fittings, lights, fans and appliances individually. Record which items belong to the sample flat only. Ask who installs them and when they will be delivered. Compare the annexure with the agreement before paying for upgrades, and use it again when you inspect the finished home.

Claim	Written detail to request
Gated community	Entry arrangements, shared users and maintenance responsibilities
Semi-furnished	Itemised inventory of included fittings and appliances
Fully furnished	Furniture and appliance list, specifications and condition
Modular kitchen	Cabinet layout, materials, hardware and included appliances
Private terrace	Identified area, access rights and upkeep responsibilities

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1.9.8 Which checks apply to both a new home and a resale flat?

The same layout words can appear in a new-home brochure or a resale listing. The definitions of studio, duplex and penthouse do not change with the seller. Sachi’s reading: in a new purchase, compare the approved plan, builder’s specifications and agreement with the promised layout. For resale, also compare the home as it stands with the approved plan and the seller’s documents. Ask whether a balcony was enclosed, a stair changed or a terrace room added, and have your lawyer or architect check the relevant approvals. Do not assume that a visible alteration is approved merely because an earlier owner made it. Inspect the furnishing inventory for condition as well as presence. For either purchase, keep the exact unit number, indoor area and outdoor rights in view, then assess the total price against those details rather than the headline label.

A resale penthouse or duplex can carry changes the current owner never disclosed. Ask the seller for the original sale deed, the latest tax receipt and any society or association no-objection certificate for alterations. Walk the unit against the approved plan floor by floor, and note any wall, window or terrace structure that the plan does not show. For a resale builder floor, ask who signed the earlier sale deed for each floor and whether the land share recorded there matches what is now offered to you. If the seller cannot produce the approved plan, request it from the local planning authority before you proceed, since a missing plan is a bigger risk than an unfamiliar label.

Before your next visit, request the dimensioned plan and write down the three features you need in daily use. That gives you a concrete way to compare a studio, duplex or penthouse with a regular flat.