Multi-family Housing: Definition, Types, and Design Principles

Multifamily housing is an increasingly relevant solution in cities, both due to the need to increase housing supply and the importance of making better use of urban land, rehabilitating existing buildings, and creating more efficient, comfortable, and durable living spaces.

For investors, real estate developers, or building owners with transformation potential, this type of project can represent a significant opportunity for value creation. However, before moving forward, it is essential to understand the urban planning framework, the potential of the plot or building, the maximum number of allowable units, predictable costs, and the technical challenges involved.

In this article, we explain clearly and objectively what multifamily housing is, the types that exist, the main advantages and disadvantages of this type of investment, and what should be considered in a construction or rehabilitation project.

What is multifamily housing?

A multifamily housing property consists of a building or a complex of constructions that integrates two or more independent units within a single lot or plot, intended for the housing of different families.

Unlike single-family housing, which is generally associated with a house for one single family, multifamily housing brings together several residential units in the same plot, building, or built complex.

This model can take different forms and stands out for balancing the privacy of each individual unit with the shared use of access ways, infrastructure, common areas, and, in some cases, outdoor spaces.

What types of multifamily housing exist?

Multifamily housing can assume different formats depending on the land, location, urban planning parameters, and project goals. The main types include:

• Apartment buildings, common in urban areas;

• Gated communities or residential condominiums, with private units and shared amenities;

• Semi-detached or townhouse complexes, where multiple units share boundaries or structural elements;

• Housing estates, composed of several residential buildings or blocks;

• Rehabilitation of existing buildings, when an old property is converted to integrate multiple units;

• Mixed-use developments, which can combine housing, commerce, services, or parking facilities.

More than just the typology, what defines the quality of multifamily housing is how the project responds to the location, the usage, and the daily life of its residents.

Examples of Multifamily Housing by MJARC Arquitetos

Green View Tower, Covilhã

The Green View Tower is born from the reuse of an unfinished structure in Covilhã, transforming an interrupted building into a contemporary residential project. The intervention allowed the recycling of a significant part of the existing structure, reducing construction waste and breathing new urban life into a building that had been left unused. The project integrates housing, landscape, and efficiency, seeking to establish a more balanced relationship between the tower, the city, and the Serra da Estrela mountain range.

Multifamily Housing, Coimbra

This project explores the relationship between collective housing, privacy, and the quality of outdoor areas. The composition of the facade, the windows, the balconies, and the patios contribute to creating a more balanced experience between interior and exterior spaces, allowing each unit to maintain its own unique relationship with light, the city, and the inhabited environment.

Riverside Condominium, Santa Comba Dão

The Riverside Condominium is based on the rehabilitation of an existing structure, valuing the location’s potential and its relationship with the surrounding landscape. Designed as an nZEB — nearly Zero Energy Building, the project combines structural reuse, energy efficiency, and a more conscious approach to construction. The intervention demonstrates how multifamily housing can regenerate existing structures, lower environmental impact, and create new ways of living with greater comfort, performance, and permanence.

Why is multifamily housing important in cities?

Multifamily housing allows for a more efficient use of land, contributing to meeting the housing demand in established urban areas. This model can help reduce uncontrolled urban sprawl, bring residents closer to services, transport, and amenities, and make the rehabilitation of existing buildings more viable.

However, densification does not simply mean building more. A good multifamily project must guarantee quality of life:

• Natural light and proper ventilation;

• Thermal and acoustic comfort, alongside privacy between units;

• Outdoor spaces, clear circulations, and a balanced relationship with the surroundings.

From MJARC’s perspective, multifamily housing must be conceived as a way to create urban and residential value, rather than just an operation to multiply built square footage.

Advantages of investing in multifamily housing

Multifamily housing can be highly advantageous for both residents and investors, provided that the project is well-located, properly scaled, and developed with strict quality standards.

Advantages of multifamily housing for residents

• Shared maintenance costs: General maintenance expenses and building improvements are divided among the co-owners, making it financially more advantageous.

• Enhanced safety: The presence of multiple residents in the same building naturally increases the overall sense of security.

• Access to common spaces and services: The ability to enjoy shared areas (gardens, pool, gym, courtyards) and a closer proximity to urban amenities in central zones.

Advantages for investors and developers

• Better use of land: Allows for maximizing the potential of a single plot by creating multiple independent fractions under the same roof.

• Diversification and real estate appreciation: Risk mitigation through multiple streams of return via the sale or rental of individual units.

• The opportunity to rehabilitate existing heritage, transforming old buildings into highly efficient residential assets with a greater strategic scale of intervention.

Main challenges of a multifamily project

Designing a multifamily property requires a much more complex approach than a single-family home. It is not just about creating several apartments, but developing a building that is functional, comfortable, technically viable, and coherent with its surrounding context. The main challenges involve:

• Urban planning framework, access ways, circulation, and parking layouts;

• Ensuring acoustic and visual privacy between the distinct units;

• Selecting the correct materials to lower future maintenance costs and ensure seamless urban integration.

How do you design multifamily housing?

The design of a multifamily housing project begins with a careful reading of the location, the terrain or existing building, legal constraints, solar orientation, and access points. At MJARC, this initial phase is crucial to understanding the true potential of the intervention and defining a consistent strategy. It is necessary to articulate the urban scale, the collective scale of common areas, the private scale of each unit, as well as the technical and sensory aspects (light, materials, and space atmosphere).

Rehabilitating a multifamily building: what to evaluate?

Rehabilitating a multifamily building can be an excellent opportunity, particularly in established urban areas, historic centers, or properties with high appreciation potential. Before moving forward, it is essential to evaluate:

• The structural state of the building and the presence of pathologies or moisture issues;

• The possibility of reorganizing units, accessibility, natural light, and ventilation;

• The legal and urban planning framework, alongside predictable construction costs.

The role of the architectural project in rehabilitation is to find the exact balance between what the building already is and what it has the potential to become.

Who to turn to for developing a multifamily housing project?

Investing, building, or rehabilitating a multifamily property requires a technical team capable of guiding the process from the very first decisions. It is essential to understand the urban planning constraints, the maximum potential number of units, foreseeable costs, and the overall feasibility of the intervention.

At MJARC Arquitetos, we accompany projects from the initial feasibility analysis all the way through design development and construction supervision. If you are evaluating building, investing in, or rehabilitating a multifamily property, get in touch with us to begin your project analysis.

Frequently asked questions about multifamily housing

• What does multifamily housing mean? Multifamily housing is a building or a residential complex that integrates two or more independent units intended for different families.
• What is the difference between multifamily and single-family housing? Single-family housing is designed for one single family. Multifamily housing integrates multiple housing units into the same building or built complex.
• Is an apartment building considered multifamily housing? Yes. An apartment building is one of the most common forms of multifamily housing.
• Is it possible to convert an old house into multifamily housing? It depends on the urban planning framework, the physical characteristics of the building, its structural health, and the local regulations. We strongly recommend conducting a feasibility study before moving forward.
• Is multifamily housing a good investment? It can be highly lucrative, especially when supported by a prime location, solid market demand, a well-developed architectural project, and strict control over construction or rehabilitation costs.