Very small patio umbrellas

Make your own to fit. Buy a piece of material to size and gaffa tape it to the wall. Use bamboo sticks or other to stand at the front. Its very easy.

Another good idea, thanks very much.

www.greenfingers.com/superstore/product.asp?dept_id=200304&pf_id=LT2626D
Clamp these on your chairs?

shysal yes, I think that's in the US, but that' s th sort of thing I've been looking for. Thanks tophoenix and lucid for the suggestions, all three are smaller than any I've come across, and I'll be ordering one of them. I won't say which to stop any gloating.

homecreate.info/interior-home/cool-umbrellas-for-contemporary-outdoor-furniture.html/attachment/terrace-mates-balcony-umbrellas-for-contemporary-outdoor-furniture
I can't see where this company is based, so it may be the US one you mention, looks like a good idea.

My first one is smaller!

We bought this one for our balcony and it fits perfectly

Small Parasol

Or this one from Ikea

www.ikea.com/gb/en/catalog/products/S29930040/

This one is only 1.5m

www.amazon.co.uk/Stripes-Parasol-Camping-Sunshade-Umbrella/dp/B0089KS1WC/ref=sr_1_5?s=outdoors&ie=UTF8&qid=1373899587&sr=1-5