134:10 A person should be careful not to cut the material for the schach himself; he should buy it. In an emergency, he may cut it himself after asking permission from the owner of the land. (If the public has permission to cut wood in the forest, there is no problem – Mishnah Brurah 637:11.)
134:11 One may build a succah during chol hamoed (even from scratch – Bi’ur Halacha 637:1 s.v. oseh succah).