This is from a Jan 2014 webinar from a vendor, slides posted online:
"22. Do these rules apply to business loans secured by a principal dwelling? No, the force-placed insurance rules do not apply to business purpose loans: loans for business, commercial or agricultural purposes. It does not matter that the business purpose loan is secured by a principal dwelling. 12 C.F.R. §§ 1024.5(b)(2); 1026.3(a)(1)
23. Should similar notices be sent for commercial properties? Business purpose loans are not subject to the force placed notice requirements under the CFPB rules. A business loan is defined as the extension of credit primarily for a business, commercial or agricultural purpose. 12 C.F.R. §§ 1024.5(b)(2); 1026.3(a)(1). However, it is a best practice to follow a standard 45 day (two notices) letter-cycle for business loans."
http://www.wncfirst.com/NEWS/WNC_Webinar_qa.pdf