Tarping: The most common temporary fix is to secure a tarp over the suspected area. If the roof leak is very large or you can't pinpoint the exact source, covering the area with a tarp is a reliable yet temporary solution. Use a heavy-duty, waterproof tarp that's large enough to cover the entire suspected area, plus a few feet beyond that for full coverage. Secure the tarp in place with roofing nails or bricks to make sure it's taut; this makes it possible for additional water to run off rather than pool on top.