Building a Cold Frame with Used Windows

Build a Cold Frame with Used Windows

Building a cold frame is a great way if you want to make your growing season last longer. It is simply like creating a green house, but with almost different tools. In general, it is not that complicated and costly to build a cold frame. Here are the steps how you can build a simple cold frame using old windows frame.

About Cold Frames

Cold frames are used in countries where the season is changing constantly. A cold frame helps gardeners to start planting quicker in spring. A cold frame is also used to let and leave plants to grow well, especially plants that tend to need the cool season to grow. A cold frame basically is a box with a clear and safe cover that is able to open and close well. A clear cover is needed to allow the sun to shine through it in order to enable the plants to gain the right amount of sunlight. In warmer days, the cover is slightly lifted so as to let out hot air, which will not suffocate the plants. Plants are put inside the cold frame and there are some gardeners who prefer theirs planted into the soil in the frame.

You will need:

  1. Old window frames
  2. 2×2 wood and stainless steel screws
  3. Hinges and 1×1″ woods


  1. First, build two frames of the same size as the frame of your used window. You can use 2×2 wood and stainless steel screws. For a stronger frame, use 2×4 woods for bottom frame. Cedar or redwood will last longer than pine wood.
  2. Then, connect the two frames with legs. The front legs will be slightly shorter than the rear ones to make the tops slope forward. The sides should be covered with cedar or redwood. Leave the bottom open so the whole frame can be set over plants that are already growing.
  3. Place the used window over the top and attach with hinges on the back which is on the higher side. You can add a simple hook and eye closure in the front to protect your window top from being blown away by strong winds.
  4. Next, you will want to be able to open the top partially and leave it that way since the sun can warm the cold frame too much on warmer days. The simplest way is to add support by adding 1×1″ pieces held by a single screw on either side of the box on the inside. These can be swiveled up to prop up the frame too.
  5. Keep your cold frame small if you prefer it portable. And also, build more frames to cover more space. However, you can build it in any size you like if you want to leave it in place and remove the window top so it stays all year.

Image Credit:

Flickr CC

Additional Reading:

Building & Using Cold Frames: Garden Way Publishing Bulletin A-39

Black & Decker The Complete Guide to Greenhouses & Garden Projects: Greenhouses, Cold Frames, Compost Bins, Garden Carts, Planter Beds, Potting Benches & More (Black & Decker Complete Guide)