[mrusk]

I think alot of guys here need to take ICPI or retake it.

[Matt Kulp]

Originally posted by mrusk
I think alot of guys here need to take ICPI or retake it.

I may not agree with everybody on this site for installation methods, but who are you to make a statement like that. You make it sound like ICPI is the only way. Where do you think ICPI gets all of there tech specs...FROM CONTRACTOR field studies. I agree that they set a standard that should be followed, but there methods are not the only that work. If I remember correctly, you have been in the bus. for a few years, and you are telling guys that have been doing this longer then you are alive that there methods are incorrect? Even better, you know better because you read about it in a book and took a two day course.

I apologize about the rant, but I am so sick of guys quoting ICPI and NCMA specs and trying to make everyone else seem inferior for not adhering to there methods. We use the majority of all of the methods they recommend, but I am always looking for other methods that may improve our quality and efficiency.

I have been certified by ICPI and NCMA for 4-5 years now and I can tell you of numerous times when engineering firms have went against both in certain applications.

[lasting impress]

Not too change the subject, but Im from Canada and Ive never heard of ICPI and NCMA. Just wondering what their standards are. Just for curiosity purpose.

[Stonehenge]

mrusk - putting in plainly, you're not showing appropriate respect to others. Start today or you will lose your privileges.

@ lasting - their Canadian HQ is in your area:

561 Brant Street
Burlington, ON L7R 4K2

[Raj Venugopal]

Originally posted by lasting impress
Not too change the subject, but Im from Canada and Ive never heard of ICPI and NCMA. Just wondering what their standards are. Just for curiosity purpose.

ICPI is quite active in the States, but not so much in Canada. Some hardscapers travel for their courses and certification, but I know it's just not that big here. A lot of guys get their training here through apprenticeship. I believe ICPI has a good site if you keyword search them.

[B.lock]

25 years ago, surface compaction over pavers bedded by 1"-1 1/2" of FA-2 sand would result in many broken pavers. As the manufacturors have changed their mix designs to increase PSI strengths, broken pavers are no longer a problem (we currently screed at 1/2"-3/4".)
We recognize that the bedding layer - no matter what the material - is a composition of fine aggregates that become vulnerable to water saturation and migration problems.

My question was basically this: have we evolved our installations to more base material (which I believe most agree with), followed by less bedding material?


I recognize every project and its paver are different. On a new material made by Unilock (Umbriano), we've had better results increasing depth of bedding sand back to 1"-1 1/2" in order to allow for some lateral movement under compaction of the larger (16"X16") paver. So its not that I'm anti-sand, its just that I favor a situational approach to the specific product used.

My point is that I STRONGLY reject the theory of "if it's not ICPI spec - it's wrong." Matt Kulp's right about that.

[johnkeegan]

What do the manufacturer's say to use in their spec. guides?
I've done it both ways, with sand and with stone dust. I've seen no difference in long term results. I swithched to sand now because it simplifes things... for me.
This may just be a case of honest disagreement. I don't think ICPI has a hidden agenda. It's not like they have a vested interest in selling sand.

[Stoneman705]

I betcha Stonehendge's side by side test of sand vs concrete block dust shows that concretre/limestone granular waves more in a freeze/thaw climates. I think this is due because dust absorbs or the water clings to the molecules or something, and the dust releases water slower. This causes lateral movement in the stone and I would imagine over the long term waving would set in. I will get my Gold Oak membership soon.

tbh my first ever job left me in charge and not an employee. It was a 1800sf driveway, 9 steps down the side of the house, a garden bed and a small walkway. A big job for someone who didn't know nothing.

After furiously studying tech manuals, books, pamphlets, library, internet etc, I decided to take no chances and used NO sand, just straight 6i 3/4 minus or A gravel mixed, and topped with 4i gravel screenings all compacted in 2" lifts. Dunno what the fines were.

We swept/vibrated 4 times and broke 30-40 of the Allen Block pavers, (4x8, 8x8,12x8) around 85% were the 8x8's. The Allen block pavers were "concretish". The surface beneath these pavers were all smooth and fully supported the pavers. So I dunno if this was a bad batch or simply the product you get from a low-end supplier. Probably both :/

You have to be careful working screenings, the more it is raked, the more separation between sizes you get. So you end up with some pebbling. It was incredibly difficult screeding gravel shavings!

So for my next job I used 1" sand, compacted once and "pooled" between the soldiering course with the gravel screenings layered up to the edge - a packer width which my soldiering/edging sat on. This gave an added benefit of providing a screeding surface to work from.

If I keep using sand, I am going to go with what B.Lock said about adjusting sand depth.

I think sand is used since it's a helluva lot easier to screed with than gravel screenings. Concrete dust is easier still, but Unilock only warranties on sand.

[schaafsma]

Has anyone ever used crushed, recycled glass as a bedding base for pavers? And, will the pavers be effected if more than 1-1/2 of bedding material is used to fill in over the ill prepared base. For example, if the compacted ABC base was lacking in a few areas and the crushed glass was used to compensate for the lack of base, will this effect how the pavers turn out? I have always believed that the surface of the final compacted base will equal the final outcome of the pavers. Any opinions about this?

[sandim]

Certainly not a real expert here...but I agree with Paul. The number one reason for failure is improperly compacted base and sub-base. Also, ICPI standards now call for washed mason sand, not stone dust. Certain companies like Techo-Bloc will not warranty their product if it was installed with stone dust, not sand.

[Rex Mann]

[QUOT, ICPI standards now call for washed mason sand,

I think you mean washed concrete sand

Peace,

Rex

PAVERSINSTALLED.COM

[Euroscapes]

Another thing i brought up at an ICPI course when I attended was:

If you use a screenings base to make it level, then use polymeric sand in the joints would that not create a better interlock since now it goes all they way to the bottom of the paver and all completely hardens.

vs. having the bedding sand come part way up the joint and polymeric part way down...

opinions?

-Cam

[AZTLANLC]

Polymeric sand hardens up but try this, spread a thin layer anyplace and then moist it after it hardens up try to break it and you'll notice it doesn't take any effort to do it, any minor movement from the pavers and the polymeric will break, polymeric sand I believe has many advantages over regular sand but will have the same interlocking effect compare to regular sand if it stays in place.