Brick Patio and landscaping blanket??

Hey guys, I'm laying down a paver-stone patio and was wondering if I should put the landscaping blanket under the road crush or on top of it?? Thanks for any advice/input!!

 

Unless you are laying with an extremely wide joint, you do not want or need it under the pavers at all.

 

Spray the base with Roundup before laying pavers if you are really worried about the existing weeds/seeds.

Any new weed seeds would be airborne, so the tight joints on interlocking concrete pavers will severely limit seeds from taling root. If you do get any, you can give them a short spray when you do your yard.

Never, never put a solid sheet of poly under your pavers.

Dick

 

You could use geotextile under the granular material to stabilize the soil underneath if it's unstable, otherwise you don't need any textile or plastic sheet underneath interlocking brick. You can place the bricks directly on your granular or use screenings on top of the granular if you wish (like many contractors do).

When the weeds come up between the bricks, and it's just a matter of time before they do, then you can spray the whole thing with a commercial soil sterilant, pull out the weeds, or apply salt to the joints and sweep it in or spray water on it with a gentle spray to wash it into the joints. I personally do the salt thing because it's a cheap form of soil sterilant compared to the commercial options.

 

If you are installing interlocking concrete pavers, they should be set on a 1" sand (concrete sand meets the specifications) setting bed that is screeded on an appropriate base!!

If you wish to slope the paver surface, slope the base to maintain a consistant 1" sand setting bed thickness. Screenings are crushed and are too angular. - See the ICPI site(icpi.org) for complete information.

Dick

 

For a patio, you could get away with screenings for a setting bed, but you will still need a fine concrete sand to sweep and vibrate into the joints, so using concrete sand will eliminate using two different materials.

Dick

 

Jagged edges on screenings is the least of the problems with them, as they are too fine to worry about that. The biggest problem is that screenings (or stone dust) is a very crappy material that is really cheap waste picked up by contractors to cut costs. Screenings is a material typically composed of the fines resulting from crushing limestone. Since all limestone is crap because it is relatively soft and effervesces with water and then turns into mud, screenings turns into mud that much quicker because it requires little effervescence - it's already very fine.

Concrete sand, on the other hand, is typically a harder material from alluvial deposits (deposited by glaciers many years ago), will last much much longer, and will not become mud.

Contractors like to push the idea that screenings packs well, which it does, until, of course, it breaks down.

 

Quickcurrent, you must realise that the innernet' is a big place. In this part of the country, limestone fines or screenings, make an outstanding base, as well as the finest raw material in the United States for cement production. Our native sand is very hard, true, but is 100% due to weathering of granitic batholiths and depostional limestones/sandstones, with never a glaicer involved (in the last 100 million years, anyway).

Interestingly enough, New Orleans and the surrounding areas have some of the hardest aggregate in the US, in spite of not being within 150 miles of anything that could be considered "rock". With no local point sources, all of the gravel mined is glacial, and only the hardest makes it that far down the Mississippi.

Just a reminder that what prevails in your world does not pertain to the overall situation.

 

Interesting comments, but you're making assumptions as to where I get my knowledge from, certainly not from the Internet on this topic. FYI, I am a civil engineer with many years experience from around the world, including the good US of A. And, believe me, limestone is great for the production of cement, but that's where its true usefulness ends. As a granular material it is garbage for any application, but unfortunately has to be used for economic reasons where it is prevalent.

What you call "rock" is not the only hard material or even necessarily hard for that matter. Rock comes in many hardnesses from very soft to very hard depending on its composition. Similarly small particles of sand and gravel come in many different compositions and that determines their hardness and usefulness. Sand and gravel from alluvial deposits as well as those deposited by such things as rivers tend to be hard and excellent for any construction application. Similarly granite from quarries (among other materials) makes excellent crushed rock. Limestone is never desirable in construction for either crushed rock or fines (waste from crushing) and is only used out of economic need.

Peace...........

 

I will defer to your education, but disagree with your conclusions.

Graded crushed limestone makes one of the finest foundations for a road possible. It has low absorption, is angular, exceeds required compressive strengths, heals autongenously and can be considered to be a flexible paving system.

As an example of how good an aggregate in cementious concrete it actually is, here are links to three test reports:

The first is a normal weight 8" CMU with limestone aggregate.
http://www.swconcrete.com/documentation/8x8x16%20Smooth%20Face%20White%20Limestone.pdf

The second is a normal weight 8" CMU with alluvial (granitic) aggregate.
http://www.swconcrete.com/documentation/8x8x16%20Regular%20Normal%20Weight.pdf

The third is a light weight unit with expanded shale aggregate.
http://www.swconcrete.com/documentation/8x8x16%20Regular%20Light%20Weight.pdf

As you can see from the tests, the limestone aggregate CMU tests stronger than the other two. It is also lighter. It does have a 2% higher rate of absorbtion.


Edit (no we don't).

Take it as a discussion, I am always willing to learn.

 

I have stated my case. My conclusions are from my many years of practical experience, watching roads being re-built after some years in use and requiring a complete excavation of the old crushed limestone broken down into a jelly-like mess when wet, railroad ballast being replaced after one year in use because it was so badly deteriorated (in fact most railroads stopped using limestone because of the high cost of frequent ballast replacements), pathetic results of abrasion tests of limestone in the lab, etc. They are not mine alone. These are well known facts by those in the know and shared by all my colleagues. So they are not open for discussion and I am done with this thread, no offense meant.

You may choose to agree or disagree, that is your prerogative. But it doesn't change a thing. You sound like a contractor or a limestone supplier, lol.

I have no interest whatsoever in promoting any one material over another, just in offering facts for the benefit of the members in this forum.

 

Actually, I am neither. I do have 25 years of practical experience in heavy construction and commercial masonry, though. The fact that you are unwilling to discuss the issue makes it appear that you are indeed an engineer. <Shrug> Makes no difference to me.