- Are often on disused or derelict land.
- Are more available in the North and Midlands (but most housing demand is in the south east).
- Are valuable as existing buildings can be split up into more homes on any one site.
- The site has already been developed so reduces urban sprawl.
- Use unsightly areas for building developments, so improves the urban environment.
- Are found in urban areas, so building housing there reduces demand on car use.
- Are more expensive to build on as often the land needs to be cleared first (especially if land is contaminated from previous industrial use).