Rab Cirrus / 3M Thinsulate FL600 ??

http://multimedia.3m.com/mws/media/984276O/3m-thinsulate-featherless-insulation-technical-data-sheet-pdf.pdf

Trying to correct datasheet url

Jeff,

You asked, “That would be pretty impressive compared to Primaloft Gold or Climashield Apex wouldn’t it?”

The short answer is “No”. The longer answer is that for a 200 g/m2 4×4″ quilted jacket, the clo/oz for this insulation is .695 clo/oz (700 FP version) & .627 (600 FP version), versus .920 clo/oz for Primaloft Gold, and .820 clo/oz for Climashield Apex.

The primary benefit of this insulation for manufactures is that they can make a cheaper version of an existing down jacket, using their same blow-in insulation fabrication manufacturing line.

The primary benefit of this insulation to retailers is that it is loftier than a comparable down filled jacket; so, uninformed consumers will think it is warmer.

How are you arriving at the .695 clo/oz numbers?

Is 100g/m² equivalent to 4.2oz/yd² ?

The 200g/m² fl600 with a total clo of 3.9:

200g/m² = 8.4oz/yd²

3.9clo / 8.4oz = .464clo/oz which seems low.

How can 3M claim that FL600 is equivalent to 600fp down (which they do) if 600fp down has clo of about .85/oz?

Jeff,

This is a summary of my calculations:

600 FP is the volume of the blown insulation tested for fill power. It doesn’t mean it is the same clo as down at that fill power. The clo value generally goes up when the insulation density is increased but, again the curve will be different from down.