The single stack

• The single stack system's concept is to group appliances around the stackw ith a separate branch pope serving each . 
• Applications have proved successful in high rise buildigs of over 20 storeys . 
• Branch vent pipes are not required
• Branch pipe lengths and falls are constrained and are carefully selected to prevent loss of trap water and seals. 
• The stack should be vertical below the highest sanitary appliance branch . 
• The vent part of the stack may reduce to 75mm nom . dia when it is above the highest branch .