An inflatable building is a structure

Structure

Structure is a fundamental, tangible or intangible notion referring to the recognition, observation, nature, and permanence of patterns and relationships of entities. This notion may itself be an object, such as a built structure, or an attribute, such as the structure of society...

 constructed using two layers of membrane

Tensile structure

A tensile structure is a construction of elements carrying only tension and no compression or bending. The term tensile should not be confused with tensegrity, which is a structural form with both tension and compression elements....

 connected together, typically using spars

SPARS

SPARS was the United States Coast Guard Women's Reserve, created 23 November 1942 with the signing of Public Law 773 by President Franklin Delano Roosevelt. The name is a contraction of the Coast Guard motto: Semper Paratus and its English translation Always Ready...

 made from the same material. The cavity formed between the layers is pressurized with air producing a rigid structural element which allows large span structures to be achieved. The key difference between air-supported buildings and inflatable buildings is that air-supported buildings require airlocks at all the access points to prevent air being lost when doors are opened since the entire occupied space of the building is pressurized.

An inflatable building only requires pressurized air within the cavities of the walls and so does not require airlocks since the occupied interior of the building is at normal atmospheric pressure. Since a much lower volume of air is pressurized, inflatable buildings require less power for continuous operation.

The air contained within the walls of an inflatable building becomes a true structural part of the building. The membranes used in the construction of such buildings are typically less than 1mm thick, so the amount of membrane used compared to the volume of air contained within the walls is incredibly low (typically less than 0.5%). This makes inflatable buildings efficient in terms of the amount of raw materials required to construct them.

The small amount of material used in the construction of inflatable buildings makes them highly portable

Portable

Portable may refer to:* Portable building, a manufactured structure that is built off site and moved in upon completion of site and utility work...

. When a building needs to be moved, the air can simply be allowed to escape enabling an entire building to be packed into a small volume compared to its inflated size. The building can then be transported easily to its new location and re-inflated.

Nowadays, inflatable structures and inflatable buildings are used in many ways including membrane roofs and covers

Roof

A roof is the covering on the uppermost part of a building. A roof protects the building and its contents from the effects of weather. Structures that require roofs range from a letter box to a cathedral or stadium, dwellings being the most numerous....

, sail

Sail

A sail is any type of surface intended to move a vessel, vehicle or rotor by being placed in a wind—in essence a propulsion wing. Sails are used in sailing.-History of sails:...

s, buildings and pavilion

Pavilion (structure)

In architecture a pavilion has two main meanings.-Free-standing structure:Pavilion may refer to a free-standing structure sited a short distance from a main residence, whose architecture makes it an object of pleasure. Large or small, there is usually a connection with relaxation and pleasure in...

s, airship

Airship

An airship or dirigible is a type of aerostat or "lighter-than-air aircraft" that can be steered and propelled through the air using rudders and propellers or other thrust mechanisms...

s, furniture

Furniture

Furniture is the mass noun for the movable objects intended to support various human activities such as seating and sleeping in beds, to hold objects at a convenient height for work using horizontal surfaces above the ground, or to store things...

, airspace structures, boat

Boat

A boat is a watercraft of any size designed to float or plane, to provide passage across water. Usually this water will be inland or in protected coastal areas. However, boats such as the whaleboat were designed to be operated from a ship in an offshore environment. In naval terms, a boat is a...

s, escape slides, security mattresses, swimming pool

Swimming pool

A swimming pool, swimming bath, wading pool, or simply a pool, is a container filled with water intended for swimming or water-based recreation. There are many standard sizes; the largest is the Olympic-size swimming pool...

s, covering

Covering

-Mathematics:*In topology:** Covering map, a function from one space to another with uniform local neighborhoods** Cover , a system of sets whose union is a given topological space...

s, game

Game

A game is structured playing, usually undertaken for enjoyment and sometimes used as an educational tool. Games are distinct from work, which is usually carried out for remuneration, and from art, which is more often an expression of aesthetic or ideological elements...

s and castle

Castle

A castle is a type of fortified structure built in Europe and the Middle East during the Middle Ages by European nobility. Scholars debate the scope of the word castle, but usually consider it to be the private fortified residence of a lord or noble...

s, air bags and many other applications.