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View Full Version : Laying pavers on an "asphalt binder"


little green guy
10-22-2008, 11:55 AM
I'm working on a bid for a state funded historical renovation project, the work includes selective demolition, concrete and asphalt removal and installation of new pavers (900 sq ft). The specs are calling for removing the existing concrete to a depth of 6" and laying the new pavers on a 3" asphalt binder, instead of the conventional QP/ sand (ICPI) method.

I have never seen this spec'd before and am wondering if and of you guys have come across this or done this before?

little green guy
10-22-2008, 04:59 PM
I talked to the architect and they want I-2 blacktop (base) under the pavers as the "asphalt binder"... no sand for setting, seems crazy to me... anybody have any insight on this?

tmant
10-22-2008, 06:14 PM
I have done alot of brick work using that method, one was a street being changed into an outside mall. The specs. were asphalt, then a adhesive to hold the brick down. I think the adhesive was called Karnack. The only problem is the asphalt has to be where you need it and nice and flat. There is no way to shim the brick to get them flat if the asphalt is off. The Karnak seems nice and thick and would shim nicely but when the sun beats on it, it squishes up between the brick. Not good!

Paver Gangster
10-23-2008, 01:10 AM
Unless there is a structural issue at the jobsite that would warrant such a spec, my hunch is that it's a specifier using old paver cross sections from over a decade ago when some companys were calling on architects and engineers and telling them this was the way pavers were installed (no, really).

My suggestion would be to have a pavier manufacturer rep call the specifier, and get him updated info, as for tmants post, in addition to what he mentioned, its messy, and you cant pull the pavers out easily to make a repair after the fact, eliminating one of the main advantages of the system, and the drainage is non existant.

Not recommended in most cases, you are correct. Perhaps you can find out for us why they are insisting on this bed.

little green guy
10-23-2008, 10:17 PM
I had the GC put in a request to change the spec with the engineer and he said they would accept compacted stone dust, so I guess that solves that problem... I don't know why they spec'd that, probley like you said paverganster... just going off an old spec.

tmant- was they asphalt you where laying over already there, or did you lay the asphalt? The whole method of laying over blacktop just seems backwards to me.

thanks guys

tmant
10-24-2008, 06:02 AM
I did 2 jobs in sepeate locations on the same street, both were brick laid on asphalt. The blacktop was already there but was resurfaced to lay the brick. The only good part is all the prep was done, we just laid the brick, it went real fast. One part we laid in Dec. when it was real cold and the Karnak was way to thick to spread so someone had the idea to heat it with a torch. Its real flammable;) After alot of running around it went out and spread nice.
We are doing another app. just like that now, another streetscape. This time a sidewalk with the same specs. The same architect on different jobs specs. a gravel base compacted, 4" of concrete, 1" of sand and then the pavers. Their office does alot of huge jobs all around the country.