In the UK the most commonly used lightweight aggregate is LYTAG, a sintered fly ash, also known as pulverised fuel ash (pfa). Other aggregates, made from a variety of raw materials, are shown in the Table below.

The density of the resulting concrete will depend on the type of aggregate used. Lightweight aggregates may be used for the coarse aggregate in conjunction with natural fines, or lightweight can be used for both coarse and fine aggregates.