brick paver landings

[mtlogcabin]

The frost depth in a paticular jurisdiction is not the real factor if frost heave will occur.

From ASCE 32-01

The ability of the soils to retain moisture while allowing capillary moisture transport are what should be considered. Silty soils are great for this, coarse sand and gravel with limited fines have a very low susceptibility to frost. Clay soils tend to block the capillary movement so they are slightly higher than coarse sand and gravel when it comes to suspectibilty of frost heave. To be classified as a non-frost-susceptible no more than 6% of the mass of undisturbed soils or fill material must pass through a #200 mesh sieve in accordance with ASTM D422

Washed gravel will meet that standard. Think of all the railroads built on gravel all over the country and no frost heave. Why because it does not support the capillary action required to for ice lens formation and growth.

 

[Francis Vineyard]

Gravel footings and beds near or on clayey soils are susceptible to frost heave?

Afterthought backfill must be well drained and if it's an addition beyond the point it should be evident. Contractors usually submit an engineer report when constructing on backfill. No worries.

Francis

 

[David Henderson]

What if they wanted the stairs or steps to empty on to the lawn, say rear yard deck?

 

[Frank]

Ok say we put down below frost depth foundation for the landing--

How do we handle the seasonal vertical movement of the ground surface adjacent?

Max 1/4 inch vertical step for accessibility--ground moves few inches seasonally frost heave or shrink swell soil issues-- at some point you have to float to the sidewalk.

 

[JBI]

"Deck" and "Balcony" are both defined in the ResCode and neither definition would apply to brick pavers be they as a 'patio' or a walkway. If the pavers also incorporate a walkway would that then be required to provide frost protection?

Frost depth in my State ranges from 36" to 84", depending on where in the State. I know of no jurisdiction here that requires frost protection for a patio.

 

[KZQuixote]

Our climate is particularly destructive for concrete because of that pavers are used extensively in Central Oregon. I've installed many such projects including many thousands of square feet of paver walk ways at The High Desert Museum. Four inches of compacted base rock is all that is needed.

To require footings, piers and a slab to support nine square foot landing is an abuse of the code.

Unless you were to require continuous footings and a stem wall under the slab, there'd be no guarantee that the frost heave wouldn't lift the slab off of the piers any way.

Bill