Decks, Patios, Porches and Docks - Brick on sand?!

I'm putting brick on a part of my yard that's enclosed by a 10 ft retaining wall. I've been told that I should put plastic down on the leveled dirt before I put down the sand to help with drainage. That seems like it would prevent water from draining. I'm putting in two three inch drains in the ground (and shooting out of the wall) and sloping the sand/brick toward the drains. Do I need the plastic under the sand? Or should I just put the sand directly on dirt? Thanks!

Not enough info. What part of the world, what type of brick ( mortared or interlocking, clay or concrete), what type of dirt, and is the water from the walls being directed onto your pavers?

Bricks are normal old red brick pulled out of an old patio. My plan is to put sand, then brick, then concrete between them. And the water from the wall will not go directly on them. And I live in Southern California. I'm not sure what type of dirt. It has been compacted with one of those gas-powered tampers you can rent at Home Depot. Is that enough info?

So long as the edges are restrained, you can just put them on sand, cover them with sand and run the plate compactor on them, and then sweep sand to fill the joints. No concrete needed.

Is the plate compactor that tamper I was talking about? And I don't need concrete at all?

The plate compactor is a vibrating motor sitting on a metal plate. A tamper will generally have a smaller plate and look kind of like a pogo stick.

Something doesn't sound right.

How is the water supposed to get to these drains if you have sand between the bricks? Unless you have a monsoon, any rain will drain through the sand joints and never reach the drains you plan to install.

I'm not sure where the plastic idea came from, but that will do little more than trap water and to some point act as a weed block, so that can be discarded in favor of a commercially availble weed block fabic if you want block weeds and still let rain water perc through the soil.

Like I said, just confused how these drains will ever see any water.

The compacted sand will allow very little water through the joints. When I do pavers under trees, for example, I widen the joints and use coal slag so that some water WILL penetrate. Realize, of course, that when laying brick pavers in a sand base, you do not lay them with a standard 3/8" joint; it is an 1/8 or less.

Tscarborough - Just curious, since I will be laying a red brick walkway over sand with compacted rock underneath soon - Is there a standard spacing when laying brick in sand?

What would be the down-side of the wider spacing?

thx

When laying pavers on a sand setting base (1" thick), put the pavers as close together as possible. Vibrate a fine sand between the joints with a plate vibrator to get stability and strength.

The area should be restrained to keep the pavers together for strength. For a pato or walkway, brick should be OK. For a driveway or heavier use, use interlocking concrete pavers.

The pattern you use has an effect on the strength and stability of an insulation. A herring bone pattern is much more stable than running bond, or a square basketweave.

Dick

The proper way to lay pavers, concrete or clay, is to place them with a consistent effort. The idea is not to lay them too tight or too loose, just slam those puppies in place as fast as possible while maintaining bond and pattern. Done correctly, several people can lay together, but done incorrectly it is possible to tell who laid what, where. Concrete pavers and real clay pavers have teats on the side to delineate the spacing, regular brick do not and are thus harder to get consistent.

The best way is to lay the paver, not pull it tight to the already laid units. Just put 'em down and check line and pattern every few courses. After they are down and before you sand them, use a screwdriver to get the visual lines right, then spread your sand and compact them.

I find it easier to hard trowel the sand base before laying, but this is not a recommended practice.

To maintain permeability, use landscape filter fabric. This will prevent the sand from mixing with the soil, but allow for drainage. Be sure to tamp the leveled soils to prevent settling. Is this a paver style install?? If so, you should consider using a compacted aggregate base for stability.