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Replies

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  Ian Street October 26, 2014 at 5:27pm

  James, I use concrete, as opposed to MOT Type 1 on most drives nowadays. However, it depends on what the sub- soil is. On chalk I wouldn't bother with concrete. On sand/clay... I would use a bare minimum of 100mm, relatively dry mixed concrete, raked, levelled and wacked. Then, about every 1mtr, perforate the concrete with something like metal road pins. When preping the grit, fill the road pin holes with grit. The holes will aid drainage and filling them will prevent settlement.
  Hope this makes sense?!
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  mark harris October 26, 2014 at 8:36pm

  http://www.pavingexpert.com/faq_subbase_conc.htm

  read this from the leading paving expert
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  James November 3, 2014 at 9:57pm

  Thanks for the advice Ian and Mark. Does perforating the base not weaken the strength of it ?
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  Colin Hunt November 4, 2014 at 6:48am

  We started block paving in 1985 and have always used a 100mm lean mix concrete base, no sub-base, raked and whacked as above. We still go back to some of the gardens and none have dipped/sunk round MH covers and are as sound as the day they were laid.
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  Ian Street November 4, 2014 at 7:14am

  James, never had a drive fail yet, with the concrete. No rutting... If you don't put in holes and water goes down to grit, grit will turn to soup !
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  mark harris November 4, 2014 at 2:33pm

  I have never put holes in lean mix base ,and never had a problem, done lots of estate roads blockpaved over tarmac subbase with no holes, blockpaving is inpermable one laid properly,so the sand stays moist under blocks.each to there own but i see no point in doing it as a road pin hole will serve little use.
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  Colin Hunt November 4, 2014 at 5:01pm

  Nor me.
  
  mark harris said:

  I have never put holes in lean mix base ,and never had a problem, done lots of estate roads blockpaved over tarmac subbase with no holes, blockpaving is inpermable one laid properly,so the sand stays moist under blocks.each to there own but i see no point in doing it as a road pin hole will serve little use.
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  mark harris November 4, 2014 at 6:46pm

  Has anyone ever had sand go liquid using lean mix with no holes.i doubt you will ever find one
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  Lawncare-4u.co.uk November 6, 2014 at 8:06pm

  by grit do you mean #capping dust' or sharp-sand ? im a bit stunned at above comments and im no pro!
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  mark harris November 6, 2014 at 9:54pm

  grit is whats is best to use as laying course for block paving, can be sharp sand or grit mix,