Even an insulated year-round greenhouse doesn’t need a finished floor as a house does. Most of the footprint will be used as a planting area, which may or may not need a level finished surface. Your flooring option usually depends on how you want to grow in the greenhouse – whether growing directly in the soil, raised beds, or in an aquaponic or hydroponic system.
Make sure you insulate your foundation so that the floor and soil below it stays a stable temperature.
If growing directly in the soil, your greenhouse won’t have a floor. You can use pavers, flagstone, gravel or wood planks to create walkways if needed.
Stone, pavers or gravel
These are some of the more popular options because they work well with raised beds. Most of our clients build raised beds that connect directly to the soil beneath the greenhouse (i.e. no flooring material beneath the beds). We recommend this so plants root systems can grow deeper into the soil below grade. We recommend creating walkways between the beds out of pavers, flagstone or crushed gravel.
The other option is using a concrete slab. This is a more popular option if growing with aquaponic systems, self-wicking beds, or on tables that need a level long-lasting surface. (However you can also create a level surface with gravel or stone as shown in the photo above). Concrete has a number of advantages:
- Things can be moved more easily if they are on wheels, such as the self-wicking raised beds in the photo, right. Wheel barrows are also easier to handle.
- It can be easily washed down
- A concrete slab can also act as your foundation. More in our foundation blog here.
- You can still incorporate our Ground to Air Heat Transfer (GAHT) system. The concrete provides additional thermal mass which helps stabilize temperatures.Concrete does come with a significant cost however. We recommend getting an estimate from a local contractor if you are considering a concrete slab.
- Like any material in the greenhouse, the floor needs to withstand high levels of humidity, and thus we don’t recommend plywood flooring.
- Drainage is important to think about. We often recommend installing a floor drain in any type of flooring.