No stovepipe shall pass through any roof window or weatherboarding and no stovepipe in any building with wood or combustible floors, ceilings or partitions shall enter any flue unless such pipe shall be at least twelve inches from such floors, ceilings or partitions, or unless it is properly protected by a metal shield, in which case the distance shall not be less than six inches. When stovepipes pass through wooden partitions of any kind or other woodwork, they shall be guarded by either a double collar of metal, with at least three inches air space and holes for ventilation, or by a soapstone or burnt-clay ring not less than one inch in thickness extending through the partition or other woodwork.