How to waterproof my shed?

abdulahi

Hi there my shed has been leaking in water and the contents in there have gotten a mould on there. What can I do?

JacobZ

A warm welcome to the Bunnings workshop community, it is fantastic to have you with us.

Sealing up a shed is not always easy because they aren't really designed to be watertight; rather, their focus is on being lightweight and easy to construct.

If you can identify where the water is getting in, and post some photos, I'd be happy to advise what could be done in specific areas.

To seal it up as best we can, you'll need to use things like flashing tape and silicone on the outside of the shed to cover any water entry points.

You could also check out the recommendations in How to waterproof a shed floor for examples of how to seal the bottom edge of the shed.

Let me know what you think and if you have further questions or details to add, please don't hesitate to add them.

Jacob

Jason

Hi @abdulahi,

Is that light we can see between the two roof panels?

Let me tag other helpful members for their thoughts: @TedBear, @Nailbag, @Dave-1

Welcome to the community.

Jason

Dave-1

Good afternoon @abdulahi

I think @Jason has spotted the first thing to approach. That roof spine has lost its cap by the look of it. You can see light through the length of the spine.

Something along the lines of this Fielders 390mm x 2.4m Zinc Roll Top Ridge Id prefer flatter but couldnt see any in Bunnings, colourbond does have them so maybe the special orders desk would be able to help you out.

Water also looks like its coming in from the bottom edges, I would suggest to mount the things you want to store on shelving or cut down pallets.

Dave

Nailbag

Hi @abdulahi

A few things to note:

1. Garden sheds are not designed to be waterproof or even prevent moisture from entering without some form of modification.

2. The light you can see through the top sections of the roof that others have noted is very normal in both shed and even more substantial metal roof designs. So, unless rain is obviously entering here, then this isn't the source of your issues.

3. The likely source is from the ground where thew bottom of the shed walls meet the concrete slab. With the concrete dry, run a thick bead of this Sika product internally along the bottom of the shed walls and more thickly over any fastening points. Then the next time is heavily rains check to see where there are spots missed and mark them. When dry add additional sealant and so on. This is how I have successfully sealed my own and many other sheds.

4. Lastly as I mentioned garden shed are not designed to be water/weatherproof. If you are storing moisture sensitive items in there, then you may need to consider additional storage requirements like sealed tubs etc.

Nailbag