To provide a construction method capable of sufficiently ensuring following efficiency to a joint section even if a sheet building material has comparatively small elongation.

When the sheet building material is constructed for a basic material having the joint section, after the joint section has been filled with the ceiling material, a fiber is contained as a necessary component, a putty material having elongation percentage of 50 to 1,000% is applied by a width of 3 to 100 times of a joint width with the joint section as the center, and the sheet building material less than 2% in elongation is stuck thereon with an adhesive. A net-like body can be made to intervene in the inside or the upper part of the putty material.