Hybrid base construction for patios and driveways in Ottawa
A lot of changes have happened in the Hardscape industry since I started almost 10 years ago. When I started it was industry standard to use GA for the base and stonedust for the bedding layer, there was nothing else, that’s all the suppliers carried - specifically for Hardscape construction or interlock, So I thought…
I started attending as many classes and hardscape shows I could get to and getting certified was of utmost importance. I always felt there had to be a better way, and it was there all along. The shows and classes had started talking about permeable paver construction even ICPI talked about it and how clearstone doesn’t need compaction, that’s when it struck me, why not use a permeable base with regular pavers?
I am always looking for quicker faster better ways to install, if there’s a product or method out there I want to know all about it.
One of those ways is what is now called a hybrid base which is essentially regular pavers installed over a permeable base.
Through the past 10 years we have shifted from a base constructed of fines (GA and Stonedust) to what we now call a hybrid base and have seen a big shift with many other contractors following suit.
The hybrid base for paver installation is constructed in a way that
* we don’t get freeze/thaw expansion problems that you get using a dense graded base
* You get built-in drainage,
* Efflorescence is minimized
* Easier to install with no worries if your installer compacted properly as it is 95% compacted as is.
One note to mention here is this installation practice has not yet been approved by ICPI. But, it is becoming widely accepted even by ICPI instructors, because it is that effective.
Take a look at railroad tracks for instance, they are built on what is essentially an open graded base, and have been for over 200 years! Even manufacturers of pavers have recommended this method and some have gone as far as voiding their warranty if stonedust was used.
I’ll list some of the pros and cons of using a hybrid open graded base in Ottawa.
Pros
#57 stone gets delivered and installed at 95% compaction before the compactor even gets turned on. So a 10 yard delivery of 57 stone is very close to 10 yards installed. GA on the other hand, 10 yards gets compacted and loses approx 25% to 7-8 yards - ever wondered why your calculations were off and had to go get another 2,3 or 4 yards?This translates to inefficiency and time lost and money out of pocket.
Efflorescence is minimized or even eliminated
57 stone is not affected by frost and heaving because water has space to expand when it does freeze in between all the stones.
Eliminate drains and make an area permeable
Easier to work with in the rain
#9 stone used for the bedding layer doubles as winter grit if you happen to do snow removal services
No worries if your employees compacted GA properly every 2-3 inches to achieve 95% compaction - this is THE number 1 cause of failures down the road.
Cons
Edge restraints are tricky to install but still doable.
#9 stone is only available in very limited locations in Ottawa
Greely sand and gravel - Depot
Karson - quarry
Tomlinson - quarry
Can-Lock
Kott will be carrying it in 2019
ICPI hasn’t technically recognized it yet as an authorized installation method.
I believe it’s coming and they are waiting on test results.
As you can see the Cons are minimal.
At Peartree Property Services we are strictly hybrid base construction, you will not see stonedust on our job sites ever.
We believe in long lasting quality installations and believe this will be the standard in short time.
Are you a Hardscape contractor? Are you using this method?
Are you a homeowner? Are you convinced that this is how you want your next project installed?
Let me know…