In the majority of our systems, we bury it four feet. Residential will have a layer at two and four feet. But for the commercial greenhouse, it can be as deep as 12 feet where we can really get that consistent temperature of the earthHowever, many experts found that due to typical foundation depths for greenhouses and the economy of excavation, four feet is a sufficient level of soil temperatures. However, it may vary based on your location, and it may not be adequate by high-performing soil temperatures.