Housing Disaster

My RBA built house in Dawn Park Ext 7 (Boksburg) is 5 years old. In the 5 years the maintenance costs keep escalating as a result of low quality materials and poor workmanship. To date I have had my roof tiles and bedroom ceiling fixed due to rain leakage and damage 3 times (by RBA).MY OWN COSTS are geyser burst and was informed I will have to change the pipes from plastic to copper asap as the plastic pipes freeze