Willow screening is great. I've used it round 3 sides of my run, it's very effective at wind breaking, excludes most of the rain, and provides airy dappled shade in sunny weather. It gives a very nice natural-looking effect in the garden, covers the mesh and makes a good background for shrubs and plants. Snow does blow through it, as I found last year, but this isn't very common where I live, although anyway I added some clear tarp for the winter on the inside of the N. and E. facing sides. You need to measure the height of the sides and then choose willow screening which is a few inches lower than the max. measurement. Its possible to cut it horizontally, but it's so stiff and strong that its very hard on the hands, (a lesson I learned the hard way!) and it doesn't have to go right to the top in any case. It's easy to cut it to fit from top to bottom, just cut the connecting wires with wire cutters.Cut 10cm. further on than the measurement you want to end up with, then unpick the spare canes and twist together the wires which had held them in place, to stop the rest it from unravelling. The spare canes that you've unpicked are good for gardening. It's easier to cut a piece when you get to a corner, than to try to wrap it round. If joining pieces on a straight run, overlap by about 10-15cm. Make sure you get willow, not reed screening, as the reed screening is too lightweight to be effective and doesn't last more than a year before blowing to bits - (another hard-won lesson!)
Get plenty of staples, 2cm wide as they will need to cover 1-2 canes when you nail them to the top, sides and bottom framework about 10-15cm apart (assuming you have a wooden framework?) Also get plenty of cable ties, about 30cm. long, to use in 2-3 rows across the panels between top and bottom. Fixing it is quite easy if there are two people on the job, as to start with you need one person to support the roll in place, resting it on the ground on the outside of the mesh, so wind will blow it on to the framework, not away from it) and the other person to stretch it as far as possible and staple it. Then you need one person to poke the cable ties through the mesh, and the other person to push them back from inside, enclosing several canes like a big stitch. When it's first fixed it looks as if the cable ties aren't needed, but if you don't use them, it sags in time, because it comes rolled up and takes a while to expand. Just cut off the ends of the cable ties when you're done, for a neat finish.
Does the roof have a gutter? This will help a lot to reduce the amount of rain that blows in under the edge of the roof panels.
Get plenty of staples, 2cm wide as they will need to cover 1-2 canes when you nail them to the top, sides and bottom framework about 10-15cm apart (assuming you have a wooden framework?) Also get plenty of cable ties, about 30cm. long, to use in 2-3 rows across the panels between top and bottom. Fixing it is quite easy if there are two people on the job, as to start with you need one person to support the roll in place, resting it on the ground on the outside of the mesh, so wind will blow it on to the framework, not away from it) and the other person to stretch it as far as possible and staple it. Then you need one person to poke the cable ties through the mesh, and the other person to push them back from inside, enclosing several canes like a big stitch. When it's first fixed it looks as if the cable ties aren't needed, but if you don't use them, it sags in time, because it comes rolled up and takes a while to expand. Just cut off the ends of the cable ties when you're done, for a neat finish.
Does the roof have a gutter? This will help a lot to reduce the amount of rain that blows in under the edge of the roof panels.