Gravel driveway sub-base (drainage)

[riph72]

Hello all,

I'm getting a driveway replaced with gravel - should the sub-base be type 1 or type 3, or does it not matter a great deal for gravel? I'm mainly concerned with drainage/permeability issues...

My builder seems to think type 1 will be fine (and I do think he's speaking from experience!), but I'm still curious to see what the consensus is...

Thanks,
Richard.

 

[angelboy]

I used type 1. It's up to 200mm an I had a 4t fully loaded dumper on it a few months back with no problems at all.

 

[riph72]

Thanks. I wasn't actually clear in my original post, my concern was about the permeability of type 1 - I would imagine most gravel driveways have been laid with type 1 historically, without much flooding trouble?

 

[angelboy]

Should be fine. I have no problems.

 

[jeds]

Type 1 isn't classed as permeable. Use a permeable 4/20 sub-base.

 

[angelboy]

Type 1 isn't classed as permeable. Use a permeable 4/20 sub-base.

Good to know - thanks.

 

[angelboy]

https://www.gov.uk/government/uploa...achment_data/file/7728/pavingfrontgardens.pdf


Mine was done pre-2008 - but I still don't have a problem with standing water

 

[ban-all-sheds]

The Paving Expert site may have good info.

 

[r896neo]

type 2 is what would be used under a permeable surface e such as permeable block paving.

You need a much heavier roller to compact it properly though

 

[jeds]

type 2 is what would be used under a permeable surface e such as permeable block paving.

You need a much heavier roller to compact it properly though

Type 2 is not classed as permeable. The only MOT spec that is permeable is type 3. Use type 3 if you don't mind large 40mm stone or a 4/20 sub-base if you want 20mm stone. Either will do the job.

 

[riph72]

So how permeable is type 1, knowing it's not likely to be as permeable as type 3?