The hooks are attached to the walls of the house and toa tree on the other side of the garden

Thank you very much for this information. I will now ask my cousin who lives in San Diego to search out for a "used" sail from someone who can afford to get a new one. I love to "reuse" stuff.

You must have attached loops to the sail in areas where there were none....or did you insert grommets and loops? This is a great idea! I have been searching for a canopy of sorts for over a year and thought I would have to custom make it......which can get expensive. Last year I searched for a cover for a 17 ft. boat and it was over 1,000 to have it made. I finally ordered one on-line for 158.00.

Uh, oh, my husband may not find his sale next time he's ready to sailing! I'm thinking he may have an extra one for a smaller boat we used to have? This one for his current sailboat would be too big anyway!
What is the height of this particular sail? In West Texas we have plenty of wind but less water for sailing, so the anchoring will be a real issue. You've got the base of the sail on the house and a tree for the top, right? (Not the correct nautical terms...)

Correction-SAIL!