The Manpower Ministry (MOM) said this is an emerging trend of concern.
It said most fatal falls involved workers doing roof maintenance work, replacement of skylights and removal or replacement of roofing materials in factories.
In such accidents, work procedures were found to be unsafe and contractors were negligent and irresponsible.
MOM has summoned 150 small roofing contractors to attend work at height awareness and compliance sessions in August this year.
In the first nine months of this year, MOM has stopped work at 37 worksites, and uncovered more than 1,800 height safety and health violations.
More than half of these worksites were also slapped with fines.
The ministry is also stepping up inspections till the end of this year. Recent inspections found that some worksites had unsafe access and a lack of proper fall protection equipment.