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How to add drainage under deck?

Budding Browser

How to add drainage under deck?

Hi in coming days want to tackle decking project by myself for my new house. Deck will half over concrete floor and half on ground. Do I need to put screed to make floor slope for drainage under deck? What sort of product are available?

Bunnings Team Member
Bunnings Team Member

Re: decking

Hello @harry5


Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thank you for sharing your question about decking.


I suggest before you lay down anything on the ground, make sure that it already has a slope. The other thing I recommend is to provide an adequate drain set-up so that when the rainwater flows under your deck it will be diverted away. It is often safer to have both options available for your deck. 


Once you've made a slope and provided drainage, I suggest using weedmat and drainage gravel under your deck. The drainage gravel is ideal for these situations as it will not be carried away by the rain because they are quite heavy. It also allows water to pass through and hold the weedmat in place.


Please keep us updated with your progress, we look forward to seeing the start of your decking project.


If you have any other questions we can help with, please let us know.




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