Build your own greenhouse using recycled windows

A recycled (or new) window frame is used to make the front of your new greenhouse. The dimensions of the other components of the greenhouse are determined by the size of the window frame and the type of frame you choose. Because of this, the following instructions outline only the most important steps and provide you with the critical tips you need to complete this project. You must determine the necessary measurements for yourself.

The first diagram (above) illustrates the components that we used to build the body of our greenhouse: two sides (A), a back (B), a roof (C), a front board (D) and a bottom (E).
In order to build a greenhouse like ours, you will require all of these components. However, you must determine the correct size of each component based on your frame. For reference, the width of the front board, the roof and the bottom correspond to the width of the window frame you’ve chosen. The depth of the roof and bottom match the depth of the sides.

Place an appropriately-sized three-ply wood panel on your work surface and sketch out the dimensions for components A through D (Figure 2). Remember that the front of the greenhouse will be set at an angle to accommodate the window frame. To determine the length of this diagonal line, trace the diagonal using the window frame as a guide (Figure 3).
Refer to Figure 4 to determine shape of the sides (A). Here, we have drawn both sides on a single wood panel.

You can purchase a pre-cut screen printing plate (E) for the bottom of the greenhouse at a DIY store.

Once you have taken all of the necessary measurements and drawn them onto the three-ply wood panel using a pencil, you can begin to cut out the individual components using a jigsaw (Figure 1).

Once you are finished, make sure to carefully sand each cut edge (Figure 2).

Now you can begin to assemble the body of your greenhouse. The diagram above shows the exact positions of each component (Figure 1).
Important: to make sure that the greenhouse is stable, it is important to use squared timbers in the construction. The positions and sizes of these timbers can be found in the diagram and the list of materials. The length of each squared timber depends on the individual dimensions of the other components. Cut the squared timbers to the correct lengths.

We recommend starting by attaching the squared timbers to the back (B) (Figure 2). Then you can easily attach the sides (Figure 3). You can use this method to attach all other components to the body.

Attach the bottom (E) last, making sure to mount the casters to the bottom before attaching the bottom to the body (Figure 4).

When you are finished constructing the body of your greenhouse, you can begin to design the interior. There are no rules here – simply design the interior to suit your gardening needs.

In our version, we added two additional squared timbers (I) and a shelf (K) to the upper part of the greenhouse (see diagram from Step 3 and Figure 1 in this step). Naturally, each component must be sized to fit your individual project.

In addition, we recommend lining the bottom of your greenhouse with a section of pond liner. In order to fix the pond liner in place, you may have to unmount individual squared timbers. Clamp the liner behind the timbers and cut off the overhanging edges of the pond liner using a craft knife (Figure 2).

When you are installing the pond liner, make sure to include space for a drain. To build a drain, you must cut a hole in the bottom plate (see diagram). Once everything aligned properly, mount the pond liner using a tacker or other tool. 

The lower part of the greenhouse with the pond liner is perfect for a small herb garden. To learn how to create your herb garden here.

Now it’s time to put the finishing touch on your greenhouse by adding the window. To mount the frame to the body, first detach the windows and clamp the frame to the body using G-clamps. Fix the frame in place using 2 to 3 screws on each side.

Once the frame is fixed in place, you can reattach the windows.

Since you probably want to store your greenhouse outdoors, we recommend finishing it off with a coat of weatherproof paint.

We hope you enjoy your new garden!