The 6 most popular shed foundations � reviewed. and the supported roof is why you are building a shed in the first place! this makes choosing the right foundation important. if you get it wrong, you get a sloping shed which is ugly and sticks out like a sore thumb.. Floor-less foundation when you want to build a shed without a floor; simple skid foundation. a simple skid foundation consists of two pressure treated runners laid parallel on the ground. this is a lot cheaper than a concrete slab and has the added benefit of keeping your shed portable should you ever want to move it in the future.. A backyard shed is a useful storage space, but it becomes much less useful if it's falling over due to a failed foundation. several foundation-building methods will keep a shed standing tall, but depending on where you live and the kind of shed you're putting up, your foundation options could be limited..
