Page 1 of 1

Posted: Wed Aug 19, 2020 9:26 pm
by DorrisMorris
I've been pouring over information about sub bases including on this site and asking mates who were in the trade before their backs gave up and going round the houses.

I need 20-25 ton sub base to build up levels 150mm for path and astro. Problem is that this must be slightly permeable to help direct water into a simple drain trench that goes into a sump pit. I'm at the bottom of a hill on heavy clay. Unfortunately everyone Ive spoken to seems to have a different view of what is permeable and what isn't.

Truth be told I don't really want to have to spend well over a grand on 25 ton of type 3 as ground is clay and high water table so ground won't absorb much water in any event. I'm being offered 25 ton of crushed concrete type 1 (not MOT spec) for £250. I'm presuming there will be reduced clay content that will make it more permeable? But then this is just an assumption! Do you reckon just fork out the extra for type 3 or is it a safe (ish) punt to go with the crushed concrete?

Thanks as always brilliant site and a life saver for those of us with little practical experience of how to deal with site problems.

Posted: Thu Aug 20, 2020 10:19 am
by Bob_A
Sorry can't help but when I read

I'm being offered 25 ton of crushed concrete type 1 (not MOT spec) for £250

It reminded me of this, be careful!


Please read this

Posted: Thu Aug 20, 2020 2:36 pm
by DorrisMorris
Thank you.

That link was incredibly useful and has most definitely put me off the idea.

Posted: Thu Aug 20, 2020 6:51 pm
by dig dug dan
I was going to post the same thing this morning!

Posted: Tue Aug 25, 2020 6:52 pm
by Tony McC
How can this "material" be described as Type 1 but not MOT? It's the same bloody thing!

Admittedly, MOT is a very outdated term, but we all know what it means, and the full name of the "material" is crushed sub-base aggreate to a Type 1 specification of the Dept of Transport documentation.

It can't simultaneously, be Type 1 but not MOT!