in italian its called “shed”, i wonder if its the same in english (but as far as i know shed is only a wooden construction)
here’s a view:

http://www.edilio.it/imgprodotti/pre71511.jpg

and a detail:

http://www.rdb.it/VediMacro.phtml?IdPreview=1562

thanks!
another sketch:
http://gruppobasso.it/costruzioni/brochures/FLY-A275-minished_sez90.gif

hertfordshire shingle roof