Sure thing. First, keep it simple and sturdy. Use a double layer of corrugated metal or a heavy-duty steel deck—those are cheap and strong. Add a concrete slab on top, about an inch thick, to give extra weight and resistance. If you’re worried about pressure, nail or bolt the roof down to a reinforced frame made of 4x4 posts spaced no more than 12 feet apart. Wrap the seams with waterproof tape and add a layer of fiberglass mesh before the concrete to stop cracks from forming. Finally, make a small ventilation port with a metal grill so the air doesn’t get trapped. That’ll keep the fallout out and the costs down.