What is the "R"- Value of a log wall ?

Short Answer:  The National Research Council of Canada recognizes about R 1.2 per inch of wall thickness measured at the narrowest point, (4") resulting in a calculation of about R-5.

Long Answer:  We don't accept this.  We have lived in these houses ourselves,(in Northern Saskatchewan) we have paid the Winter  heating bills on them and we find them quite  comparable to a conventional home with R-20 walls.  In Summer we find them to be considerably cooler than a conventional house.  We feel that the NRC has overlooked the "heat-sink" effect of the logs. Their tests were conducted on 1" pine boards.  We don't dispute their results on 1" pine boards.  However, a typical Hand cut log package of ours  weighs 80 to 120,000 pounds or more .  This mass is warmed and the heat is reflected back.  In summer months this effect works in reverse and the house stays cool.  At times during the summer  we have even found ourselves opening windows  to let some heat come in - the house was too cool !