You are looking at a thermal image of a house courtesy of FLIR Systems.  The yellow areas of the house are transferring the most heat.  You will notice the usual culprits, the windows and doors.  Also it looks like the foundation of this house is not insulated at all.  If you look closely, you can see a soft yellow glow coming from under the soffit.  This is a common problem for most homes.  I'll show you why this house is losing heat at it's roof line and how it can be prevented.

     The solution to this problem is to add space at the heel of the truss.  This style of truss is known as an energy truss or is sometimes referred to as a truss having an energy heel.  This allows plenty of room to fully insulate the attic space to the outside of wall.  The current IRC (International Residential Code) has a provision for this.  The IRC requires an R-30 where the insulation can reach full depth at the outside of wall.  That's 20% less material required to achieve the same standard.  Energy trusses cost 5% to 10% more than standard trusses, but they also save you money on insulation and most importantly on your energy bill.