Stone Walkway: Dry laid or Cemented in??

[schole]

I have a 5' wide by 15' long, outdoor walkway up to our front door which needs replacing (present 2" concrete is cracked and crumbled).

Wife wants flag stone (squared, not irregular shapes).

Should I lay compacted crushed rock/pea gravel for a base then dry lay the stone and fill the gaps with stone dust??

OR, should I lay a compacted gravel base, pour a concrete slab, then mortar the stones down on top of the concrete slab??

Any thoughts on stability, durability, and cost would help. This walk will be exposed to frost, and salt in winter.

Thanks in advance!

Shawn

 

[beowulf]

I am not an expert, and not sure of how my comments might apply with the frost and salt issue, but I have laid a lot of clay brick on pea gravel -sand base. .. I have borders - RR ties or something to hold the edges, but those walks are really solid and seem to last forever. . . use a rubber mallet to tap them in, and then sweep fine (sandbox sand) over the top and lightly hose. .. it is solid. ...I have never done anything with flagstone. ..

 

[forgeblast]

i have worked with a landscaper and this is how we put paver stones down. (we are in ne pa and have some hard winters)
first we put down a 2-3 inch base of modified 2-8 (make sure you get your slopes right then so you have no standing water). then we tamp it down (walk behind tamper helps), then using 1'' gas pipe we screed builders sand and put the pavers down. then we tamp the pavers down and brush in sand. then we take a mortar and run it along the sides of the walkway to keep them from moving. that way you dont need any of those plastic things to hold your walkway in place.
Hope this helps.
Forgeblast

 

[jhb]

What kind of soil are you on?

I made a 14x20 bluestone patio on Cape Cod 6 years ago. It has not settled one bit. However, the soil on the Cape is all sand so drainage is very good. I excavated down 8 or 9 inches then leveled, added a 2 inch slope, and then laid the bluestone right in. I used the rectangular stones that come in 6 inch increments. This has been very stable.

I am, as we speak no less, building two patios and brick walkway at my new house. The entire property is on ledge, which is a problem because water has no place to drain. I have underground hills and valleys that trap the water and create soft spots. I have not finished yet, but I intend to dig down 12 inches, put in 4 inches crushed stone with perforated pipe, then landscape fabric, then 7 inches of stone dust, and finally broom sweep stone dust into the cracks after the stone is laid. I truly believe this is overkill, but the patio should last longer than me! We also are putting in a 7"x6'x3' granite step, weighs 1700lbs! My tractor can't pick that up, nor move it! Not sure how I am going to handle this yet.

The existing brick walkways were on about 6 inches of stonedust/sand, and they have been stable for 50+ years. Not sure when they were installed but I know it was pre 1970. They have settled very little.

Its not a hard task, just needs lots of muscle!

 

[ejb]

What would be the best way to "edge" a patio like this?(To provide support to keep it all together) I'd like to put in a patio by the pool using pavers, it would be about 12x24...if it was old brick I'd use either railroad ties or PT 6x6's around the edge, but with a more modern looking paver they probably wouldn't look quite right...suggestions?

BTW: I am in Mass, hard winters, poor soils...

 

[jhb]

On my patio, I am going to buy 1"x12"x16' boards, nail them together as a box and use it for edging/leveling. Then back fill, and just let them rot out. By the time they are gone, the soil around the patio will be packed, and grass/growth should hold it all together.

 

[forgeblast]

grass/growth should hold it all together
you want to be careful it may cause it to lift up. thats why we put a layer of mortar around the outside edge to hold it all together, that way when the mortar dries you can back fill right up to it and you dont have to worry about your boards rotting out.
Forgeblast

 

[jhb]

I've seen it suggested that people mix dry cement in with the stone dust, then water thoroughly when done. I have not tried this method myself, and would probably not try it. But jus thought I would throw it out there.

 

[forgeblast]

Heard that done too, but i have not seen it done. Some of the guys i worked with said they will throw a shovel of portland in with the mortar to give it a little bit more strength in the winter time.
forgeblast

 

[schole]

Thank you all for the excellent responses.

In reading over at the Fine Homebuilding Break-time site, I came up with the following link which is excellent:

http://www.pavingexpert.com/pavindex.htm

Sounds like dry laying is winning out so far. We have a fine, powdery, loam-like soil -- great when tilled for growing, but horrible for drainage when packed. I was planning on a thick base of crushed rock for drainage.

Shawn