Romans were great masters of mosaic flooring from small - scale
works for domestic interiors to enormous pavimental mosaics for
floors must be hardwearing and must be absolutely smooth, practical
objectives that are best achieved through the indirect method.
indirect method was primarily developed in order that large - scale
works could be undertaken off - site for reasons of accessibility
and convenience. Using the indirect method the mosaicist sticks
the tesserae face down and in reverse on to a temporary support
using an impermanent bonding agent (water based glue). A permanent
base (usually cement) is then prepared into which the tesserae are
set and the temporary support is finally peeled away to reveal the
front of the mosaic for the first time.
resultant mosaic surface is much flatter than that produced using
the direct method. This is a great advantage when creating smooth
finishes and is therefore ideal for floors. Mosaics made using the
indirect method are invariably grouted in order to enhance their
smoothness and durability and to make them easy to clean.