Insulating parallel chord roof trusses

Anyone ever done this in a cathedral ceiling? Mine look like this (see vaulted parallel chord)
Foam would be an easy answer, but expensive. Any other ideas anyone? I'm looking for R38. Obviously, the problem area is the webbing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file

Site Timeline is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.