900 FP vs. Overfill Upgrades

**Str1der** · 10-29-2010, 14:02

I don't have much experience hanging in cold weather, so I know very little about quilts. I want to extend my hanging season, so I started researching underquilts. I think I have decided on getting an Incubator (or possibly a Crowsnest, jury's still out on that one). I was browsing the possible upgrades available from Stormcrow, but I was a little confused. Time to expose my ignorance!

900 FP refers to a higher quality down that gives more loft for the same amount of down. Wouldn't that mean that choosing this upgrade would add no weight to the uq, but would still lower the temperature rating by 5*F?

Overfilling is literally adding extra down, so I would expect that an ounce of overfill adds an ounce of weight to the uq.

Is what I just said correct? Are there any other pros or cons for one upgrade versus the other? Is it possible to add overfill to the 900 FP down uq as well? If so, what temperature ratings would that yield?

WV · 10-29-2010, 14:08

Sounds like you've got it right, but if I really wanted to know I'd ask Stormcrow.

**Lonely Raven** · 10-29-2010, 14:09

You are correct. I asked them to clarify because I wanted to order an underquilt (and their page needs to be a little more clear)

They fill the same *weight* of down (mind you, it lofts better), and you're correct that it should improve the temp rating by 5F.

There is a point of diminishing returns...you can only fit so much down in a confined space before it starts to compress itself and you have no loft (remember, it's the air trapped in the down that actually keeps you warm, not the down!).

The Pro of 900FP is that is compresses more, and in theory you can use *less* to get the same amount of warmth as 800FP...though as mentioned, Stormcrow uses the same amount 800 vs. 900.

IMHO, if you're throwing money at a quality quilt, you might as well go Full Monty and spring for the 900FP.

**Hokie Hanger** · 10-29-2010, 15:56

I was a bit confused too. Is it that an equal weight of 900 fill down compresses more than 800 fill down or is it that you don't need as much 900 fill down to achieve the same loft and warmth so the lesser amount of 900 fill down compresses more than the same loft equivalent of 800 fill down because there is less of it?

**MAD777** · 10-29-2010, 17:10

The "Fill Power" (FP) number is the number of cubic inches that 1 ounce of down will fill (under perfect conditions, i.e. no humidity). So, 900FP will occupy 100 more cubic inches of space than 800FP.

You are absolutely correct, in that if you choose 900FP option, the quilt will weigh the same amount, but the down will loft up thicker (i.e. warmer).

If you choose and additional ounce of 800FP down, the quilt will also loft up thicker (i.e. warmer) but at a penalty of weighing one ounce more.

**optimator** · 10-29-2010, 18:31

I had a hard time deciding this too. I ended up going with the 900 fill. It should be here next week

**Wags** · 10-29-2010, 20:02

mad777 i think you are a bit off. i'm pretty sure stormcrow uses the same amount (total weight) of down for the 800 filll and 900 fill. the 900 down upgrade simply results in a warmer quilt b/c 8 ounces of 800 fill < 8 ounces of 900 fill...

**MAD777** · 10-29-2010, 20:20

Yes, I wasn't very clear with my explanation. I was meaning to compare getting an 800FP quilt custom overfilled by 1 oz, versus, sticking with the normal amount of down but going with 900FP.

**Wags** · 10-29-2010, 23:53

ahhhhhhh gotcha.

**Str1der** · 11-09-2010, 09:07

Ok, thanks all for the advice. I've decided to go with thw 3-Season Incubator with the 900+ FP down upgrade. Getting excited now! My only question left is color. Does anyone have any pictures of the Navy Blue or Camo patterns? I can't seem to find those anywhere.