Sunken pavers and ground

[DonnaL]

Hi Folks,

My questions relate to a big problem in the yard where the ground and parts of the paved path  have sunk due to disintegrating tree roots. Some of the "holes" are up to 20 cm deep and the ground very soft and spongy.

I have pulled up pavers in the sunken areas back to level plus two more pavers, removed what roots I can of the old camphor laurel but some are still solid circa 20 - 30cm diameter and taking longer to chop out.

So my question is what do I fill the holes with before I put gravel and sand in to replace the pavers? Some of these go down 50-100 cm and I wondered if normal bagged garden soil would be too soft.

Thank you.

[MitchellMc · Accepted solution]

Welcome to the Bunnings Workshop community @DonnaL. Many thanks for your question, I'd be glad to assist. 

It's fantastic to have you join us and we look forward to finding a solution. My advice would be to fill the holes with a material that doesn't easily compress like the gravel or sand that you are already using. Bagged garden soil is a bit too soft and can't easily be compacted. You might like to consider hiring a compactor to run over the area a few times to make sure you have a solid surface to start paving on. Here's a helpful step-by-step D.I.Y article on How to lay paving for a path that I trust you'll find useful in the process. Let me also mention @Adam_W to see if he might like to add to the discussion.

Please let me know if you need further advice or have questions.

Mitchell

[Adam_W]

Hi @DonnaL and welcome, welcome, welcome!
That's actually a pretty typical sort of problem with pavers that have been down for a while & likley weren't laid well in the first pace.
As @MitchellMc said the key is to do your filling with material that won't break down or compress and bagged garden soils etc. will do both.
The bigger holes would best be filled with a cheap, bulk material like roadbase or for those big holes you can get what's called fill sand. If you can't find that in bags or need larger quantities then see a landscape supplier.
You then need to add a layer of paving sand so you can get an even bed to re-lay the pavers.
To be honest... looking at that path I think I'd be pressure cleaning those pavers in-situ (maybe after treatment with a product like 30-Seconds) lifting the whole thing & doing a re-lay.
Not as hard as it sounds and then you know it's done the right way & will last for ages.

[DonnaL]

Thanks Mitchell and Adam,

It was watching the Bunnings DIY that first got me wondering about filling holes first ... you have also helped me decide whether to pull up and start again and that way I can head off other areas sinking later.  I am also unearthing mounds of various pebbles/rocks from around the plants in the gardens so they can go as hole-fill to sort two probs ... citrus tree roots can now spread better but that is another story.

One question Adam ... would it make a big difference if I pressure washed after re-laying?

Thanks again Gentleman. 

Donna

[Adam_W]

Hi @DonnaL , apologies for the delay, been knocked over by a lurgy (no... not that one...)
Okay... advantage of doing it before relay is that it will make an awful mess so that doesn't matter so much when you are then going to lift etc.
More importantly however is that it is easy to destabilise recently laid paving with pressure cleaning. After you lay you should always broom clean sand over the area and this works like a mobile grout to lock things in place. It's easy to accidentally remove this with the cleaning process.

[DonnaL]

Makes perfect sense. Thank you again for your help. It makes it less daunting. 

donna lucas