I have the same problem, my rail height is 215cm and most porches are from 225cm to 250cm. I have asked this question before and the answer was NR do various height Porch awnings, but I find them a little pricey.
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We had the same problem with our Avondale. We bought the NR porch awning and are very pleased with it. Yes they are pricey compared with the nylon new style ones but they are cheap compared with Isabella. We are very pleased with ours.
I had exactly the same issue on my little ABI which has a height of 210cms. I bought a Pyramid Weekender Plus that my local dealer said I could take home and try out on the drive. OK so it's maybe an inch either side - but for a weekend porch awning its great. As my van is only 12 foot as well - its almost 3/4 the length of the van. FAR easier than a big ole frame tent type full awning. I can put the Weekender up on my own in about 10-15 minutes.
I use a Royal on my van which is really too tall and sticks up above the van level, but it seems to work OK. You can splay the legs out which takes up some of the extra at the sides so you can pull it nearer to the van.
------------- Caz
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