This project is by Bobby from I Like To Make Stuff. Building a greenhouse is an excellent way to nurture your plants and enjoy gardening year-round.
In this step-by-step guide, we’ll walk you through the process of constructing a lean-to style greenhouse that is both functional and aesthetically pleasing.
Step 1: Clean and Prepare the Site
The first step is to prepare the area where the greenhouse will be built. At Josh’s house, there was a large open space beside the house, perfect for a greenhouse. Before starting construction, clean off the wall where the back of the greenhouse will be attached. This ensures a smooth surface for building.
To give you an idea of the size, the greenhouse will extend six feet from the wall and be twelve feet long, consisting of four sections of concrete, each measuring three feet. The entrance will be located at one end, allowing easy access from the back door.
Step 2: Build the Floor Frame
Next, it’s time to construct the floor frame using 2×4 lumber. The floor joists will be spaced 16 inches apart, following the standard building practice of 16 on center. However, for this project, you can break each section down into three equal segments for additional support.
Using a pneumatic framing nailer makes this task easier and quicker. Ensure to nail in the joists securely to create a sturdy foundation for the greenhouse.
Step 3: Level the Ground
Before finalizing the position of the frame, check the ground level. If the ground is uneven, you can use additional 2x4s as feet to help level the structure. By adjusting these supports, you can create a stable and even surface to work on.
Step 4: Lay Down the Floor
Now that the frame is in place and level, it’s time to lay down the floor. The flooring will consist of two layers: a half-inch pressure-treated plywood base topped with outdoor siding. The outdoor siding is composite, designed to withstand moisture and provides a better aesthetic than regular plywood.
Use decking screws to secure the plywood and siding in place, ensuring a durable floor that can handle the weight of people and plants.
Step 5: Assemble the Walls
With the floor complete, proceed to put up the vertical wall frames. Start with the back wall, securing the vertical pieces with a horizontal 2×4 across the top for stability. Once the back wall is in place, repeat the process for the front wall, connecting the two with additional supports.
Step 6: Add Paneling to the Exterior
For the exterior, take the offcuts from the flooring and nail them to the walls. This will serve as a base for the greenhouse covering. To enhance the look, wrap the edges with trim pieces for a finished appearance.
Step 7: Install the Greenhouse Covering
For the covering, 4×8 sheets of clear plastic were ordered. If local stores do not have them in stock, you can order them online and have them delivered to your local store for pickup. This plastic covering will allow sunlight to penetrate while keeping the inside warm.
Before applying, consider whether to leave the white sheet on the outside for reduced transparency or remove it for maximum light. The plastic sheets can be cut using a circular saw for precision.
Step 8: Create the Door
The door is a crucial element of the greenhouse. Construct a lightweight frame using the same materials as the walls. Attach the door with spring hinges, allowing it to close automatically when released. Ensure it fits snugly within the frame for proper sealing.
Step 9: Add Vents for Airflow
To maintain a suitable temperature inside the greenhouse, it’s essential to add vents. Cut holes near the top of the roof to install vent flaps that can be opened and closed as needed. This will help regulate heat on hot days.
Step 10: Install Air Registers
In addition to vents, installing AC registers at the lower part of the walls will allow fresh air to enter the greenhouse. These registers can be opened and closed to control airflow, ensuring a comfortable environment for plants.
Step 11: Finalize the Structure
Now that all components are in place, review the structure for stability. Make sure everything is securely fastened, and consider adding lag screws to attach the greenhouse to the house for added security.