This paper described an investigation and evaluation which was carried out in the
United Kingdom-UK, on the properties of masonry building block materials that incorporate
waste materials, namely: steel slag, crushed glass, coal fly ash, rice husk ash (RHA), incinerator
sewage sludge ash (ISSA), municipal solid waste incinerator bottom ash (MSWIBA) or shortened
as IBA, bound with bitumen or asphalt, named as Bitublock. The binder used was 50 pen
bitumen. The properties of the blocks evaluated were: compressive strength, density, porosity,
initial rate of suction (IRS), creep, and volume stability. It was found that the Bitublock
performance can be improved by optimizing porosity and curing regime. Compaction level of 2
MPa and curing regime of 200?C for 24 hours gave satisfactory bitublock performances that at
least comparable to concrete block found in the United Kingdom (UK). The Volume stability
(expansion) of the unit is affected by environment relative humidity.