Top Down Demolition method usually applies for high rise building demolition or low rise where working space is a constraint. By using Top Down Demolition method, demolition is carry out only one storey at a time. It is usually safest to demolish the building in the reverse order to building it, so the roof should go first. Then, part of each floor is taken out so that the debris can fall through. On some demolition project, the debris can be dropped down the lift shaft, in which case, guardrails must be provided around openings.
By normal standards, Top Down Demolition is the most common if not the only method designed for simple and cost effective demolition works. Properly planned and designed, it is actually the Most Safest way of demolition among other specially designed methods.
Top Down Method is also the most typical method used for manual demolition works. Manual demolition works is the most cost effective method but not necessary the most safest and fastest way. However, in some countries, the Manual Top Down Method with human workers is the only way for demolition capitalising on the cheaply available manual works force readily available in these countries.