4 Ways to Waterproof Your Wood Shed

A small wooden storage shed with a ramp in a backyard.
  • 5-10 hours
  • Intermediate
  • 50-500
What You'll Need
Concrete or old scrap metal
Wood treatment
Waterproof paint
Commercial sealer
Sealer gun
Eye protection

These days, wooden sheds come with a wood-based primer coating that protects them against natural weathering, but sometimes it is not enough. This is where waterproofing comes in. It can add extra protection to save your investment and everything inside! While your shed will not be perfectly impervious to moisture and some water may still find its way inside, it will certainly minimize damage. In the following article, you will learn what preventative measures you can take.

Elevate the Floor

The first thing to do is to ensure that your floor inside the shed is slightly detached from the ground. If not, your shed will be easily damaged by water seeping up from below. Moisture is very damaging and with the addition of rainwater, your shed could be destroyed in months. Use old scrap metal and concrete blocks put onto the earth as an elevated sub-structure to keep this from happening.

Treat the Wood

Source Waterproof Wood Treatments on Amazon

Adding a wood preservation treatment is a great way to keep your shed in good shape. Use it as a base coat and you can paint over it with the color of your choice. Just make sure when you buy the treatment that it is the type that you can apply paint to afterward--otherwise, any paint you add will just slide off.

The process to apply wood treatment is a simple one; you just have to spray it all over the wood, and then let it dry. You may want to use a spirit-based preservative because this type will soak more efficiently into the wood.

When finished, allow the shed to dry for one or two days. Then, if so desired you can paint over it with waterproof paint to add extra weathering strength.

Seal the Wood Shed

For the most thorough moisture protection, seal the wood, both inside and out with a commercial sealer. It doesn’t necessarily have to be designed just specifically for wood, but if it is, it will produce a much better result.

Start by sealing the perimeter of the roof, paying special attention to the corners of the shed, as that is where water typically seeps through. Then you can continue to the walls and potentially the corners at the bottom. Once you are done, leave it to dry. The key rule to remember with moisture is that if there is any way at all to get into your shed, water will find it.

Protect the Roof

You can’t have a waterproof shed if you don’t have a waterproof roof, so consider adding a protective layer to this as well. This can be done by adding sheets of old scrap metal or fiberglass to the inside. Usually, this is done as an alternative to adding a wood treatment.

As mentioned above, you may not have a completely waterproof shed, but by doing your homework like you are now and by taking certain preventative measures, you can be sure it will keep most of the moisture out, and last you for a very long time to come.

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