Tiny House

A tiny house is a small, self-contained detached dwelling, usually defined as 400 square feet (about 37 square metres) or less of floor area not counting lofts, built either on a permanent foundation or on a trailer so it can be towed. The tiny house movement promotes these homes as a way to live with less space, less cost and fewer possessions. Designing one well means fitting sleeping, cooking, bathing, working and storage into a footprint smaller than many single rooms, while still meeting the rules that govern where people may live.

What is a tiny house?

The most widely used definition comes from the building code. Appendix Q of the 2018 International Residential Code, written by the International Code Council, defines a tiny house as a dwelling of 400 square feet or less in floor area excluding lofts, as the ICC's Building Safety Journal explains. The same article notes that most tiny houses are one-storey, single-family dwellings of between 85 and 400 square feet, and that many are mounted on a chassis for towing.

That gives the field two branches. A tiny house on a foundation is a small permanent home and is regulated like one. A tiny house on wheels is legally closer to a vehicle, which brings different rules on parking, utilities and how long someone may live in it. Both share the defining feature of a detached, complete dwelling, which separates the tiny house from neighbouring topics. Compact living covers small interiors anywhere, including micro-apartments in a larger block. Modular housing is about how dwellings are manufactured and assembled, at any size, and modular design about building from repeated parts. A container house can be tiny, but it is defined by its steel box rather than its size. The tiny house is defined by scale, independence and, often, mobility.

A short history of the tiny house movement

The movement draws on a long tradition of small, deliberate dwellings, and one book keeps returning as its source. Henry David Thoreau built a one-room cabin beside Walden Pond in Massachusetts and described it, and his reasons for living in it, in Walden (1854). He even listed what the house cost to build.

"I have thus a tight shingled and plastered house, ten feet wide by fifteen long, and eight-feet posts, with a garret and a closet."

Henry David Thoreau, Walden (1854)

The modern movement took shape in the late twentieth century. The Wikipedia history of the tiny-house movement names Lloyd Kahn, author of Shelter (1973), among its early pioneers, and credits Sarah Susanka's The Not So Big House (1997) with starting a counter-movement toward smaller homes. In 1999 Jay Shafer built a small mobile home and founded the Tumbleweed Tiny House Company, and in 2002 he and others founded the Small House Society to advocate for the movement.

The next milestone was regulatory. After a membership vote of just over two-thirds in favour, Appendix Q entered the 2018 International Residential Code, giving building officials standards for lofts, ladders, compact stairs, ceiling heights and emergency escape in very small houses. For the first time, tiny houses had their own set of standards inside a model code, and a builder had something concrete to show an inspector.

Key principles of tiny house design

Make every space do two jobs

In a tiny house, rooms become zones and furniture becomes architecture. Beds fold or lift, tables slide out of joinery, and stairs double as storage. Saghan House by Sukriti Jain and Aditi Agrawal shows the approach: the whole house is an open plan, with louvered sliding folding partitions that close only when privacy is needed, and furniture that opens up to seat six people comfortably.

Use height before floor area

When the footprint is fixed, volume is the resource. Sleeping lofts free the main floor for living, and Appendix Q exists largely to make them legal. The City of Boise's summary of tiny house requirements sets out the essentials: habitable space at least 6 feet 8 inches high, lofts of at least 35 square feet, and access by compact stairs, ladders, alternating tread devices or ship's ladders. A loft used for sleeping can meet the escape rule with an egress roof window, and loft guards must be at least 36 inches high or half the clear height to the ceiling, whichever is less. Those few numbers shape the section of almost every legal tiny house, so it pays to draw the section before the plan.

Decide early: wheels or foundation

A trailer sets hard limits on width, height and weight, and pushes the design toward light framing and careful load distribution. A foundation removes those limits but ties the house to zoning. Some designs sit in between: kit-like homes that can be taken down and rebuilt elsewhere. Minima by akansha pandey, which received an Honorable Mention in the Mobitecture competition, is a compact, small-footprint home for a family of four built around an easy assembly and disassembly process.

Bring the outdoors in

Daylight, cross-ventilation and a deck or garden make a small interior feel larger and cost less to run. Saghan House maximises natural light and ventilation to cut electricity use, and in a tiny house a porch or deck can work as the main living room whenever the weather allows.

Plan the services as carefully as the rooms

Water, power, heating and waste take up a surprising share of a tiny house. Some owners sustain a tiny house entirely on rooftop photovoltaics, and any off-grid build needs room for batteries, water storage and waste systems designed into the plan from the start rather than squeezed in later.

Tiny houses on uni.xyz

Members approach the tiny house from two directions: competition proposals that test how little space a household needs, and built small dwellings reviewed in our journals. The best of both treat size as a design question rather than a sacrifice.

Saghan House, discussed above, was a winning entry in the Nano Nest 2.0 competition. Dandelion by Lara Hofbauer, Eric Schmitz, Paul Schuchmann and Sophie Bott, an Honorable Mention in the Nano Nest competition, combines living and working space on the same plot so that a resident can start a small business in a dense city, and adds a green niche that reconnects the household with nature.

Net House by 黎 张 and chuang li, entered in Nano Nest 2020, starts from the basic functions of eating, sleeping and washing and argues that a small house should offer options rather than a fixed lifestyle:

"So in modern life, the house is just a shell with size restrictions."

黎 张 and chuang li, Net House, project statement on uni.xyz

Bio-Modular by Elif Mihcioglu, Elif Sultan Kaya, Sabiha Okur and Erdem Baz, entered in the Pocket Home competition, proposes flexible, temporary housing on a vacant plot in New York City, built from bioplastic made from recycled waste.

Among built work, our journal on TreeBOX by Studio Officina82 looks at a 12 m² guest cabin raised on four timber posts in the Piedmont hamlet of Alpisella. Its faceted shingle roof reinterprets the sliding roofs of the region's traditional barchi hay barns, and the structure puts no load on the surrounding oaks.

The accessory dwelling unit is the tiny house's urban relative, and our review of Granada Form's white stucco ADU in Echo Park shows how far the backyard format can stretch: a cube roughly 25 feet on a side holding a two-bedroom family home over three levels, counting the roof. On a former garage plot in West London, Wade House by Wadhal fits a two-bedroom home into 70 square metres by redrawing the bay window, hipped roof and brick base of the neighbouring semis. And Moving "Rubik's Cube" by Yinuo Lu, chengyan lian and Jiayue Liu, which received Editor's Choice at Strata 2020, scatters raised, brightly coloured low-cost units across an open field as self-sufficient accommodation and shared space for homeless people.

Taken together, the competition work tends to explore flexibility and shared space, while the built houses in our journals show how much depends on site, structure and a precise brief. Both are worth studying side by side before starting a small-dwelling project of your own.

Challenges and future directions

The biggest obstacle is not design but permission. Zoning rules often set minimum floor areas for new homes on a foundation, and building codes have historically required sizes well above a tiny house. A code appendix does not change that on its own.

"Jurisdictions still have to vote to adopt the appendices."

Susan M. Dowty, International Code Council, Building Safety Journal (2018)

Tiny houses on wheels face a different problem. The Recreational Vehicle Industry Association treats them as RVs that are not suitable for permanent residence, and local rules against camping can stop owners from parking one on their own land. Change is happening city by city: Boise, for example, has allowed tiny homes on wheels in some zoning districts since 1 July 2025, defining them separately from recreational vehicles.

The most consequential direction may be social. Some jurisdictions now support tiny dwellings as affordable housing for homeless and low-income families, and villages of tiny houses can offer residents a transition toward self-sufficiency. That work needs designers who can plan shared kitchens, sanitation and landscape as carefully as the units.

Tiny houses for students and designers

A tiny house is one of the few building types a student can design completely, from structure to joinery. Strong thesis angles include a trailer-based home detailed to real road limits, a code-compliant loft and stair study, a tiny house village for people leaving homelessness, or a self-sufficient dwelling tested against climate data; see off-grid living for systems precedents. Small-dwelling briefs appear regularly on uni.xyz competitions, where a proposal can be judged alongside other approaches to the same brief.

Frequently asked questions

How big is a tiny house?

Under Appendix Q of the 2018 International Residential Code, a tiny house is a dwelling of 400 square feet (about 37 square metres) or less, excluding lofts. Many are much smaller, and the ICC notes most fall between 85 and 400 square feet.

Can you live in a tiny house on wheels full time?

It depends on local law. Tiny houses on wheels are often treated as recreational vehicles, which are designed for temporary or seasonal use rather than year-round living, so check zoning and parking rules before buying or building one.

Do tiny houses need a foundation?

A tiny house regulated as a permanent dwelling generally does; Boise, for example, requires tiny houses to be on a permanent foundation. Houses on trailers follow separate vehicle and zoning rules.

Are there tiny house design competitions?

Yes. On uni.xyz, small-dwelling briefs such as Nano Nest, Pocket Home and Mobitecture have produced several of the proposals featured above.

Can a tiny house be off-grid?

Yes. A small, well-insulated house needs little energy, and some run entirely on rooftop solar panels. Off-grid systems still need space, so plan them into the design from the start.

References and further reading

• The International Residential Code has a big vision for tiny houses, International Code Council, Building Safety Journal
• Tiny Houses, City of Boise Planning and Development Services
• Tiny-house movement, Wikipedia
• Walden, by Henry David Thoreau, Project Gutenberg