The biggest trailer tarp we have is the Erickson Industrial-Grade Truck/Trailer Tarp, Item # EM57051, that is 12 foot x 24 foot.
One possibility is to add another trailer tarp like the Erickson Mesh Tarp and Truck Cover, Item # EM57058, and connect them in the middle by the rivets and/or with cords and straps. This Erickson mesh cover is 10 foot x 12 foot. view full answer...