An inflatable dome is a structure in which its structural integrity is based on the use of pressurized air to inflate a flexible material from the inside.

This concept was popularized on a large scale by David H. Geiger") with the United States pavilion at Expo '70 in Osaka, Japan in 1970.[1]​.

It is usually dome-shaped, as this shape creates the greatest volume with the least amount of material. To maintain structural integrity, the pressure inside must be equal to or greater than any external pressure applied to the structure (i.e., wind pressure). The structure does not have to be airtight to maintain structural integrity; the pressurization system that supplies the internal pressure should replace any air leaks. All access to the interior of the structure must be equipped with two sets of doors or a revolving door, which function as a lock. Inflatable domes are fixed to the ground using a system of heavy weights, anchors, foundations or a combination of all of them.

It is often used in sports and recreation facilities, warehouses, temporary shelters and domes. The structure can be total, partial, or functioning as a roof. A total structure can be used for a temporary or permanent installation, while a dome serving as a roof is usually built for a permanent building.

The largest inflatable dome in North America is the dome of the École secondaire Pública Louis-Riel (Louis-Riel Public Secondary School) in Ottawa, Ontario, Canada.[2]​ It also holds the record for being the second largest inflatable dome in the world.

Shape

The shape of an inflatable dome is limited by the need to apply uniform pressure to the entire surface of the cover. Otherwise, the irregular distribution creates wrinkles and stress points that can ruin the structure.[3]​.

In practice, any inflatable surface involves a double curvature. Therefore, the most commonly used shapes are hemispheres), ovals or semi-cylinders.

Structure

The main actions acting on an inflatable dome are air pressure, wind and snow. In order to cope with varying wind and snow loads, the inflation of the structure will need to be adjusted accordingly. Modern structures have computer-controlled mechanical systems capable of detecting dynamic loads and compensating for inflation. The highest quality ones are capable of withstanding winds of up to 190 km/h (120 mph), and snow loads of up to 18 kg/m².[3]​.