G'day Sarah,

They are washable but it can be a bit of a process.
The main issue is that they need to be line/air-dried.  The sleeping bags can get very heavy and difficult to manage when they're wet, so you'd need to make sure you have somewhere suitable for them to dry.
Alternatively, if you use a liner you can wash this instead and reduce the amount of times you might need to wash the actual bag itself.
Usually, just a good airing and thumb out like an old fashion rug can be enough to refresh them, instead of having to put them through the wash.

Hope that helps.

G'day Eileen,

The Cold Mountain Canvas 900 doesn't have a removable liner layer.

G'day Jason,

Yes the 900 model has dual left and right zippers. 

G'day Tony,

The Dusk to Dawn bags are a fairly close fit, however if you're very careful about how you roll it up you may well be able to get it tight enough to fit in the bag with your sleeping bag inside of it.

G'day Karl,

I wouldn't want to say these are totally waterproof as no sleeping bag really is. The canvas is pretty good at keeping a bit of moisture off the fill inside the bag though, much better than the outer on a standard sleeping bag. You'd be fine to sleep out under your awning as long as the rain wasn't coming in too hard.