Typically, lightweight concrete is used in construction projects where the weight of conventional concrete would be too much of a burden. The most common aggregates for a lightweight concrete mix are perlite and vermiculite but there are a wide variety of other potential options as well. These include wood shavings, peat moss, styrofoam, pumice, expanded clay or shale, diatomite and many others.

This type of concrete uses air-filled voids to decrease its density without reducing its strength. The voids are created by either omitting the fine aggregate in a traditional concrete mix (no-fines concrete) or replacing the normal aggregate with aggregate that contains a high percentage of void space, such as expanded clay, shale, volcanic pumice, scoria, and cinders (aerated or foamed concrete). In addition to being less burdensome on structures, lightweight concrete also has lower thermal conductivity, making it ideal for projects that require insulation from heat damage.

One of the most important things to keep in mind when working with lightweight concrete is that it must be cured properly. If it isn’t, the concrete will not set and may become weak or brittle. This process involves wetting the concrete and allowing it to dry out.

Another way to increase the strength of a lightweight concrete mix is to add a chemical admixture like poly vinyl acetate (PVA) or white glue. This helps the concrete bind together and create a more dense structure that is able to withstand higher loads and stresses.