# Ground preparation for laying pavers



## barryrk (Apr 29, 2010)

Could tamped down pea gravel be used for the underlayment before putting sand in to lay 16" pavers?


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## troubleseeker (Sep 25, 2006)

I do not know what the "official" guidance is on this, but my opinion is that pee gravel would not make a very stable base. Since it is basically round, the pieces can not interlock, so no matter how much you tamp it, it just keeps rolling around like a bed of ball bearings.

Be interested to see what the real landscape guys think.


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## Bushman (Mar 28, 2010)

I agree. I have never used or heard of anyone using pea stone for this purpose. 
The drainage would be excellent. However in an effort to compact it the pea stone would squish out the sides. Forever moving.
Any type of sand bed would end up filtering down into the pea stone.
Thus the pavers would have to be laid directly on the stone.
Stick around maybe someone has used it and can elaborate.


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## Scuba_Dave (Jan 16, 2009)

I used pea stone under the walkway to my basement & to my pool area -4.5" pavers
The basement walkway is fine, I drive my truck across the pool walkway
So that has moved due to grading & weight of truck w/lots of weight (wood, more pvaers for another patio)
Once I'm finished w/construction & grading is corrected I'll redo the walkway

I did not vibrate compact either walkway - small
Not sure how it will work on a larger area w/sand & virbration

Pea stone was from an area that former owners filled


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## GardenConcepts (Jan 21, 2010)

the compaction is more of an issue with different size/mix stone, although angular will compact better than round. You might try adding some screenings/fines to the pea gravel to get better compaction.


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## Hoopscoach (Apr 25, 2010)

I just started prepping for a patio with 16 x 16 pavers this weekend. I framed it out and layed crushed gravel, hand tamped it and will be allowing it to settle until I put the sand and pavers on next weekend. The crushed gravel has already become extremely hard and looks to be a great surface to build on. I will let you know how the finished product looks. Just my two cents... crushed gravel seems to be a suitable surface.


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## concretemasonry (Oct 10, 2006)

If you ever build someting with real loads, you will never use "pea stone" because it does not compact unless you have something mixed in with it. For things like driveways, streets, airport taxiways (747 caliber) or harbor facilities (100 ton straddle loaders), the only thing used is a road base with a 1" sand cushion. This is for the small interlocking pavers since the larger (over 9" maximum dimension) pavers will not be stable or carry the same loads.

For large pavers, you need a compacted base plus a thin sand setting bed to eliminate cracks due to stress concentrations or base movement. A large paver has no interlock, so the stability and strength of the surface is less and you can expect some movement and possible loss of the protective sand cushion.

Without a compacted base, the large pavers are almost floating on the base, especially with high moisture contents since the aggregate is not interlocked.

Dick


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## Hoopscoach (Apr 25, 2010)

concretemasonry, can you expand a little bit on the specific base needs for 16 x 16 pavers? Thanks.


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## High Gear (Nov 30, 2009)

Road Base is crushed limestone around here and is 3/4" in size down to fines (dust).

When you use a vibrator compactor with water you will see air bubbling up 

from the angular rocks sliding together upon compacting ( and expelling the trapped air).

Use plenty of water , you will know when your using to much.

Accepted minimum paver base thickness is 6" around here for sidewalks and 

patios because of heavy clay soils. ( compact in layers).


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