Variation in gravel size for sub base
Discussion
Hi all, currently I'm in the process of laying a new driveway.
I've done 200mm of MOT type 1 subbase, needed an extra bag which has been delivered today from another supplier and the size of the stones is far larger than the previous sub base and there's far less fine material, just wondered if this is likely to cause any issues?
You can see here the new layer at the top compared with the old which has already been whacked down
It seems to be mainly large stones in the bag (where as the previous type 1 that was laid last week had a lot more cat litter sized to fine dust material).
I've done 200mm of MOT type 1 subbase, needed an extra bag which has been delivered today from another supplier and the size of the stones is far larger than the previous sub base and there's far less fine material, just wondered if this is likely to cause any issues?
You can see here the new layer at the top compared with the old which has already been whacked down
It seems to be mainly large stones in the bag (where as the previous type 1 that was laid last week had a lot more cat litter sized to fine dust material).
To ensure a smooth finish I would measure each stone on the surface from the new batch, anything above standard I would crush with a nutcracker - can't be too careful
Then mash 'em with a wacker plate.
Then mash 'em with a wacker plate.
untakenname said:
Hi all, currently I'm in the process of laying a new driveway.
I've done 200mm of MOT type 1 subbase, needed an extra bag which has been delivered today from another supplier and the size of the stones is far larger than the previous sub base and there's far less fine material, just wondered if this is likely to cause any issues?
You can see here the new layer at the top compared with the old which has already been whacked down
It seems to be mainly large stones in the bag (where as the previous type 1 that was laid last week had a lot more cat litter sized to fine dust material).
I've done 200mm of MOT type 1 subbase, needed an extra bag which has been delivered today from another supplier and the size of the stones is far larger than the previous sub base and there's far less fine material, just wondered if this is likely to cause any issues?
You can see here the new layer at the top compared with the old which has already been whacked down
It seems to be mainly large stones in the bag (where as the previous type 1 that was laid last week had a lot more cat litter sized to fine dust material).
Drumroll said:
To conform to MOT type 1 subbase it has to meet specific grading requirements. The reality is that the allowed percentage passing each sieve is very large.
So on a 31.5mm sieve you can have anything from 75-99% passing and the 4mm sieve 12-53% passing.
This^^^So on a 31.5mm sieve you can have anything from 75-99% passing and the 4mm sieve 12-53% passing.
What are you going to lay on top?
I do driveways and this type of thing drives me mad, I have got better but I am finally excepting that it doesn't actually matter, the stones just don't match 
As mentioned the difference in stone size can be quite big, you can get dusty loads or stoney loads, they aren't meant to be like that but it is.
As mentioned the difference in stone size can be quite big, you can get dusty loads or stoney loads, they aren't meant to be like that but it is.
Thanks for all the replies.
I've been putting some sharp sand into the mix to even it out a bit but it's not ideal as my wacker plate isn't the strongest.
I'm using Materials Market so don't have a say in the supplier (tried a local merchants first but they only did loose load).
I'm getting one more bag as I've decided to do down the side access as well where the bins go so hopefully the next bag will be better and I can mix them both together.
A neighbor asked if they could have a bucket worth for their water feature, some of the stones measure over 70mm so imo should never have got through the grading process.
I've been putting some sharp sand into the mix to even it out a bit but it's not ideal as my wacker plate isn't the strongest.
I'm using Materials Market so don't have a say in the supplier (tried a local merchants first but they only did loose load).
I'm getting one more bag as I've decided to do down the side access as well where the bins go so hopefully the next bag will be better and I can mix them both together.
A neighbor asked if they could have a bucket worth for their water feature, some of the stones measure over 70mm so imo should never have got through the grading process.
TA14 said:
This^^^
What are you going to lay on top?
It's going to have 40mm of sharp sand ontop then some paving bricks for the car tyres and gravel in the middle.What are you going to lay on top?
Wacky Racer said:
I dunno. When building something of this magnitude, one needs to think about the details. Perhaps the OP should give the chaps at Faslane a call and ask them about their gravel size variation. Not sure the guys at Murmansk will be especially accomodating at the moment.untakenname said:
TA14 said:
This^^^
What are you going to lay on top?
It's going to have 40mm of sharp sand ontop then some paving bricks for the car tyres and gravel in the middle. What are you going to lay on top?
(And you might consider a few small bags of 10mm clean but that's probably OTT.)
untakenname said:
A neighbor asked if they could have a bucket worth for their water feature, some of the stones measure over 70mm so imo should never have got through the grading process.
Those do look to be within spec actually: https://mineralproducts.org/MPA/media/root/Publica...Gassing Station | Homes, Gardens and DIY | Top of Page | What's New | My Stuff