How to Foam Insulate a Shed

Updated February 21, 2017

Sheds come in handy when you need to store garden, auto and lawn equipment and supplies. Lack of insulation in a shed can result in extreme cold or excess moisture exposure, resulting in damage to any temperature- or moisture-sensitive items you may be storing in the shed. Foam insulating a shed helps protect its contents from the elements, and it's a project you can accomplish with the help of some foam panel boards and other materials.

Remove the shed's existing roof so the exterior roofing structure is exposed. Lay OSB (oriented-strand board) or plywood across the roofing structure, and attach it, using a hammer and galvanised or stainless steel nails.

Lay vapour sheeting, a weatherproofing material that keeps out moisture, over the board. Use a staple gun to staple down the sheeting over the boards.

Use a measuring tape to measure the area of the roof. Measure and mark foam board panels to the correct size to fit on your roof. Score the panels with a razor knife, and snap the panels at the score mark to cut them to size.

Use a glue specifically designed to adhere to foam board panels, which you can purchase at most home improvement centres. Apply the glue to the foam boards according to the manufacturer's instructions, and place the panels over the vapour sheeting. Leave a 1/8-inch seam between each foam board panel. Place strips of duct tape over each seam.

Lay down firing strips, beginning at the top of the foam board panels and working your way down. Position the firing strips horizontally across the panels. Position an additional firing strip across the top and bottom ridge and centre of each panel.

Reposition the metal roof on top of the shed. Attach the roof to the previously installed firing strips, using a hammer and galvanised nails. Apply a bead of caulk to the nail heads to prevent damaging the foam board panels, and to create a small amount of space to promote airflow between the roof and panels.


Enlisting a partner to help you install the boards and panels will make the job go quicker and easier.


Always wear safety gloves and goggles when working with hand tools and power tools to avoid injury.

Things You'll Need

  • Staple gun
  • Staples
  • Foam board panels
  • Glue
  • Duct tape
  • Vapour sheeting
  • OSB or plywood
  • Razor knife
  • Galvanised nails
  • Hammer
  • Caulk
  • Safety goggles
  • Work gloves
  • Assistant (optional)
Cite this Article A tool to create a citation to reference this article Cite this Article

About the Author