For a westerly exposure in zone 8b, I generally advise people to choose a type III clematis, preferably one of the viticellas, since they tend to hold up to hotter conditions better than the type IIs. However I see that you are in British Columbia so the type IIs may do fine for you since you are so far north.

Any newly planted clematis is not going to be a quick grower as they tend to spend more time the first few years developing their root systems. In subsequent years, they tend to be more vigorous.

As to specific recommendations, I still tend to lean towards the type IIIs just due to my experience with them so would suggest just off the top of my head Huldine or campaniflora. You could always use sweet autumn clematis but they are so over used and can be seedy so I hesitate to recommend that one for you. If you want something that would bloom earlier in the season you might want to consider a white macropetala or alpina. If you want something that would be evergreen, one of the armandiis would work. There are several montanas that are white but they might be too big for your space.

The type IIs are not my favorite group of clematis and I don't grow any white ones except for Duchess of Edinburgh which is not a fantastic grower for me. I will leave it up to others to suggest cream or white flowering type II clematis.

I find Type IIIs much more vigorous than Type IIs and I'm in the Pacific Northwest. I have had mildew problems on the IIIs though and I know my friend in Vancouver BC does as well. He ripped out Comtese de Bouchard (sp) due to severe mildew. I'm trying to find a place for Huldine though. She is so pretty with the mauve stripe on the back.

nckvilledudes: Thank you very much for your reply and very helpful tips. I googled the Clematis's that you mentioned and they are all so beautiful. I really like the huldine and the armandii's sound perfect for me. I think I'll select a Type III.

buyorsell: Thanks for sharing your experience in getting the PM on your Type III's. Is yours growing on a wall or on a trellis? I'm going to put mine on a trellis so it will have good air flow around it, instead of on the wall. I'm not sure, but couldn't that possibly make a difference? Just my own amateur thoughts.