Granodust or more type 1 for final 25mm of sub base
Posted: Sun Jan 30, 2022 9:04 am
Hi there, just finishing off the prep on my drive before putting on the aggregate top layer (15mm granite/basalt). Unfortunately my contractor ran out of time to finish the job so it’s down to me 
Subbase is basically there, but the level just needs bringing up in a few places first. It is clear that the type 1 used (recycled) is way too chunky in places and whilst it’s been wacked down there are areas which are well compacted with little visible gaps between the particles, there are others that just look like rubble packed together! I’m not happy with this, and combined with the fact I have a small pile of clean rubble to dispose of I thought I would:
- hire a red rhino 4000 concrete crusher for a day (approx £200), crush up the rubble and take out all the chunky bits in the drive, then relevel and whack.
- bring the final level up (what’s left) with either a) good type 1 (non recycled) or Granodust.
- whack again, add first layer of aggregate then whack
- add final layer then whack.
Really grateful if anyone can validate my approach and suggest whether Granodust may be a better option for the last say 20mm of subbase (my ex-contractors original suggestion). I suppose I could avoid the crusher and just pay to muck the chunky stuff away and buy more type 1 - seems like a waste tho?
Many thanks!
Subbase is basically there, but the level just needs bringing up in a few places first. It is clear that the type 1 used (recycled) is way too chunky in places and whilst it’s been wacked down there are areas which are well compacted with little visible gaps between the particles, there are others that just look like rubble packed together! I’m not happy with this, and combined with the fact I have a small pile of clean rubble to dispose of I thought I would:- hire a red rhino 4000 concrete crusher for a day (approx £200), crush up the rubble and take out all the chunky bits in the drive, then relevel and whack.
- bring the final level up (what’s left) with either a) good type 1 (non recycled) or Granodust.
- whack again, add first layer of aggregate then whack
- add final layer then whack.
Really grateful if anyone can validate my approach and suggest whether Granodust may be a better option for the last say 20mm of subbase (my ex-contractors original suggestion). I suppose I could avoid the crusher and just pay to muck the chunky stuff away and buy more type 1 - seems like a waste tho?
Many thanks!