How to build low level deck over pavers?

[jpgc2020]

We're in the middle of a renovation that includes a big new deck around our pool. The patio tiles have just been dug up, and the builders discovered they had been laid directly on the original pavers. We're now seriously considering extending the deck into the patio to create more flow. Budget constraints mean we would do this ourselves. Would love to hear your thoughts and advice for how to do this properly. Here's the plan so far:

- as you can see in the photos, some of the pavers are not level. I'm thinking I'll remove that section in front of the pool gate (about 1.5m x 2m), and replace it with a 50mm thick, reinforced section of concrete, so that it's level.

- I'll also add a bit of self-leveling concrete to a couple of pavers that have randomly subsided, to level the surface for stability and drainage.

- theres about 60mm from the top of the pavers to where the old tiles used to finish. 

- planning to used an aluminium deck frame kit, on short (10-25mm) adjustable feet, and composite deck boards with hidden fasteners.

- the grass height in front of the pavers will be reduced so that water can flow into the pit drain.

I'd love to hear people's thoughts and advice, esp around any tips or tricks for decking over pavers, sorting out drainage issues (like should we put some builders plastic over the pavers first so that water can run off easier?) etc. thanks! 

[JacobZ]

Hi @jpgc2020,

Welcome to the Bunnings Workshop community, it is fantastic to have you with us.

In all honesty, you are in a very good place to start from compared to some decking projects. The pavers look relatively flat and stable, and you're using suitable materials for the height of your deck. 

You are using adjustable levelling feet for your deck, so there is no real need to level anything under the deck unless the difference in level is outside of the range of adjustment for the feet. If the level is outside of this range, I wouldn't use self-levelling compound or pull the pavers up and replace them with concrete; I would just lift the pavers, add a bit of paver sand, compact and level it, then put the paver back. As long as the ground beneath the pavers is well compacted, then this is a perfectly fine solution that doesn't require a ton of work.

In terms of drainage, I would grab your hose and spray all over the brick pavers and see what happens and then make adjustments accordingly. Being pavers, there are gaps between them, so water will likely drain between them. The only situation where I would be considering major adjustments is if the water did not drain through the pavers and it flowed back towards the house. If this were the case, I would be looking at adding a channel drain around the perimeter of the pavers to collect any surface water and divert it towards your pit drain. I wouldn't suggest putting builder's plastic over the pavers, as it will take away any ability for water to naturally drain between the pavers.

I think you're in a very good spot and you're asking the right questions. I can't wait to see how the project progresses.

Allow me to tag @Nailbag, @MikeTNZ and @JoeAzza to see what thoughts they might have.

Jacob

[Nailbag]

Hi @jpgc2020 

As with @JacobZ you already have an excellent foundation to build straight onto. 

He also makes a good suggestion on just checking if you don’t already know there are no low points currently collecting water within the alfresco area. If not, I wouldn’t see the need to add any additional drainage and definitely not plastic as that can potentially trap water between it and the pavers. 

Other than that I think you right to go 👍

Nailbag