I am rebuilding a pathway using brick about an inch thick. I see everyone says for a walkway to use 4" - 6" of paver base but that seems like a lot. I have clay soil underneath and I’m thinking Big Base just wants me to make a thicc base to buy more paver slag. Is a full 4" really necessary or could I get by with 2"?
I don’t know what you technically COULD do or how quickly you would regret it but I can say that, in 25+ years of landscape estimating, I’ve never seen a pedestrian paver area with aggregate base spec’d with less than 4" of base material.
4" of limestone aggregate, fabric and a 1" sand setting bed is the typical detail for clay/concrete pavers for foot traffic. The soil underneath isn’t a big consideration. A couple inches deep around here and it’s solid clay but the detail remains the same.
Moved to IMHO
It’s hard to say what you’ll need. Over clay you may need the full depth. Clay has a life of it’s own, kind of like The Blob except much slower. It might swallow your base eventually no matter how much you use. More than likely 2" of paver base or a gravel and sand mix well is probably enough. How well you contain the sides of the base will make a difference to. Bricks or large stones lining the sides will keep the base from sliding laterally out from beneath the pavers.
You say you are rebuilding a pathway. That makes a difference. What was the original material? How did it hold up? Is the base already well compacted and prepared? It may be.
Bricks will allow more water to directly seep into the underlying material than a cement walkway. Using the poly sand between may lessen that for a time.
It was straight on the dirt, no paver base. Some settling but overall not horrible
Polymeric sand has its uses but I wouldn’t use it to try to get around a properly laid base. For one thing, the extra 2" of gravel is going to cost less than using polymeric sand vs regular masonry sand and letting the water seep through.
I did a quick and dirty patio round a fire pit in my back yard. Interlocking bricks, I think 2" thick?
Not clay soil. Gravelly crap. With a very thin topsoil. Taking up the sod basically took up all the soil.
Wicked freeze thaw cycles. Just regular sand filler between.It was good enough for many years. But I am not fussy.
Only removed it to build a couple big raised garden beds.
If you are using bricks. If at first you don’t succeed, pick them up and do it better. Not like you are having to break up a cement walkway and repour.
Do you live where it rains? Where it freezes? That will greatly affect the durability of a base.
All bases (hell, all manmade everything) only deteriorates with time. The goal of any base is to remain adequate enough for long enough. What is adequate enough and long enough for you? Would you rather do a weak job, keep the cash, and redo it in 10 years or will the place be sold by then? etc.
Builder speaking.
Accepted procedure for paver base is to remove top soil and organics and excavate down to undisturbed mineral substrate. Base then needs to be prepared with material that will compact such as road crush and sand. The thickness of the base is not particularly important, what is important is that it is stable and is not going to absorb moisture and heave. Obviously you need enough workable base to level sufficiently.
Clay is completely acceptable as long as it is undisturbed or campacted properly.
The problem with topsoil and organics is they do not compact and will absorb water leading to heaving, especially in a region with frost.
I highly recommend this site if you want expert but understandable information on block paving (or any hard landscaping).