how should I double my top quilts?

[BodhiKnight]

I have a 3 season down top quilt and a 3 season synthetic top quilt. What one should I put on top when I layer them?

[Bl@ckbird]

Is put the down on top so it doesn't get compressed under the weight of the synthetic. Down is only effective if lofted.

[RevKev]

What SloGo said.

[peterboysen]

Generally speaking, unless your synthetic is super heavy, I'd put the synthetic on top. As the moisture moves out from your body, it'll cool and eventually condense to a liquid; better for that to happen in your synthetic layer since it'll handle the moisture better than down will. This has been my standard practice for layering, and I know a few other winter campers that do the same.

Of course, if your synthetic is heavy enough to significantly reduce the loft, you'll have to put the down on the outside or it just won't work. But just a little weight shouldn't compress so much as to make the down layer useless.

[dakotaross]

Depends on the capabilities of each. If you're just supplementing a little, then the down inside might work better if the down is not completely flattened. The down on the outside will already experience some loss of loft because 1) your heat won't get into it as efficiently in order to fully loft it, and 2) without warm trapped air to help it loft, damp air will likely weigh it down, not to mention settling condensation if that occurs, too.

Still, if looking to max the capabilities of each, down on top.

Might depend on how much heat is trapped by your UQ as it can rise to supplement the TQ. That typically does not happen with pads.