Patio edging construction

[machtucker]

I'm currently in the process of building a patio area and coming to the end of the excavation. I have a bedding area around the patio of about 800mm deep which will be planted with plants eventually (see my sketch for an idea of what I'm aiming for). I want to maximise the space for plants so don't want the subbase to got too far into it. When initially designing the patio I had in mind design 1 in the picture. I was just going to excavate, put the subbase down and then put the mortar and slabs on top, all in line. After consideration I think the edges might be susceptible to moving as the subbase will only be constrained by top soil. A way around this would be to go to option 2 by extending the subbase. I suppose a more belt and braces solution would be to put some concrete edging blocks to constrain the subbase and not allow it migrate etc. This is shown in option 3.

What are peoples thoughts of the most suitable solution bearing in mind that I don't want to eat too much into the planting bed?

Many thanks,

Ed

 

 

Edited March 20, 2023 by machtucker
Changed patio options from pdf to png

[Temp]

We  have option 1 and similar to 3.

 

My first job when the weather is nice will be to repair the edge where option 1 has failed just due to foot and wheelie bin traffic. Surprised but its happened. Got about 6-8 meters to fix.

 

Elsewhere we have something like option 3 but with the vertical slab higher up forming a kerb separating gravel drive from flower bed. That's held up well despite being driven over a few times.

 

 

[machtucker]

Yes I think after some thought I will do option 3. Thanks for your post. 
 

Ed