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Keith P
03-21-2005, 02:55 PM
If i want to end up with 4 inches of compacted gravel for base and 1 inch of compacted sand for paver base, roughly how many inches of uncompacted material will I need?

Thanks for your guys' patience with my questions I new to hardscaping.

Dig-it Landscaping
03-21-2005, 10:18 PM
i remember in school we were told that 1.25" of chips and dust gravel compacted to 1". sorry i cant help on the sand

zedosix
03-22-2005, 12:52 AM
Since there is very little air space between the grains of sand, it would have very little compaction.

WhohasHelios?
03-22-2005, 01:58 AM
It all depends on which specific type of material you are using. To say sand and gravel isnt really specific enough for the industry here anyways. 3/4" minus (road base) will easily compact about an inch and a quarter or so. So you would need that much more than your desired compacted levels.

Sand I will assume you are using masons sand of some sort ( washed sand) it does not compact nearly as much as someone already pointed out due to less gradation in the size of grains.

Hope that helps,

-Reuben

YardPro
03-22-2005, 08:09 AM
icpi
STRONGLY advises against compacting the sand before the pavers are laid.
compacting the pavers into the sand will give you a 3/8" settle, and will push sand up between the pavers and lock them together.

WhohasHelios?
03-22-2005, 11:44 AM
icpi
STRONGLY advises against compacting the sand before the pavers are laid.
compacting the pavers into the sand will give you a 3/8" settle, and will push sand up between the pavers and lock them together.

I remember my dear old dad used to do it that way when I worked with him. It was always a huge deal to screed the sand out completely evenly and then not step ANYWHERE on the prepared surface.

When I started up, I had a few paving jobs that I did that way, and then on one of them I had a guy working with me...He stepped on the prepared base after screeding the sand a year later there was a dip in that spot...Since then I have switched to compacting the sand as well as the aggregate.

Is the sand coming up though the bottom the only reason for not packing sand or are there other reasons we should be doing it this way?

-Reuben

zedosix
03-22-2005, 11:50 AM
You are defeating the purpose of "interlocking" if you compact before laying the brick. Why wouldn't you of taken a few seconds to level the "dip" before laying the brick?

dylan
03-22-2005, 01:39 PM
I usually increase the amount of fill required (volume) by 20% to allow for compaction.
It also works in reverse. When you excavate a hole, the material will get bigger by 20% when you go to take it away.

YardPro
03-23-2005, 08:57 AM
You are defeating the purpose of "interlocking" if you compact before laying the brick. Why wouldn't you of taken a few seconds to level the "dip" before laying the brick?


bingo

why would you not just use a 12" hand trowl to fill in the dip????

EVERY paver manufacturer will void thier warranty if they find out that you compacted the sand base BEFORE paver installation.

also the advantage to compacting after is that IF you have any unlevel areas, they can be fixed with the compactor. just run over the higher areas a little more.


the main reason to compact after is so that you can push sand up between the pavers and get a good LOCK. when you sweep sand in from the top, you will have a lot of areas that sand does not entirely fill the gap. the voids will be at the bottom of the pavers. with compacting after pavers are laid, this eliminates this problem by filling the bottom area with sand.

WhohasHelios?
03-23-2005, 10:39 AM
You are defeating the purpose of "interlocking" if you compact before laying the brick. Why wouldn't you of taken a few seconds to level the "dip" before laying the brick?
Of course we did !! But the rate of natural compaction in that spot compared to the rest of the sand was then comprimised. Hence the problem...Of course I did not just look at the dip in the sand build on top of it!!!

YardPro
03-23-2005, 08:41 PM
I call BS on that one.
after the initial compaction, sand reaches almost 100% proctor density. meaning it will NEVER compact more. there is no " natural" compaction in a 1" layer of sand after a plate tamp has run over it....

WhohasHelios?
03-24-2005, 12:44 AM
Fair enough..Like i said, it was the only time..but enough of a cost that the next time I tried compacting the sand...

I just assumed that becuase it sunk in the area that the guy stepped in, (which i did repair at the time) that that was the reason for it doing so.

I was slightly surprised to hear that..Because there are a few big paving companies here that tamp the sand on ALL their bases..So I thought perhaps I was in the wrong, but if you guys are saying that warranty is voided, then obviously that is the correct way...

BS is perhaps the wrong word..Misinformed assumption is perhaps better :p

Cheers,

-Reuben

YardPro
03-24-2005, 08:18 AM
i agree that BS was probably the wrong word. :)
i wasn't trying to be a jerk or anything, so i hope it did not come off that way.

go to www.belgard.biz and download thier installation guide.

it is basically the ICPI certification test in a short form. It goes into base, sand prep, etc.....
it should help you a lot with paver installs.

WhohasHelios?
03-24-2005, 10:27 AM
No offense taken man, thanks for the link.
-Reuben