Armour stone is natural quarried block, often several hundred kilograms a unit, set in courses to hold a grade. It fails in the same ways a segmental wall does, but the repair is a different trade problem: nothing moves by hand, so the first question on every quote is whether equipment can reach it.
A segmental wall can be rebuilt by hand anywhere a wheelbarrow reaches. Armour stone cannot: each unit needs a machine to lift it, so the route from the street to the wall has to take that machine, and the ground has to carry it without being destroyed.
That is why an armour stone quote starts with a walk of the access rather than a measure of the wall.
Where a machine can reach, the work is relatively quick: units are lifted off, the base under the bottom course is rebuilt and compacted, drainage goes in behind, and the stones are re-set to a string line.
Where it cannot, the honest answer is sometimes that the wall stays as it is, or that a section is rebuilt in a smaller product instead. We would rather say that on the estimate than discover it with a machine stuck in a side yard.
Where a machine can get in, what it has to cross and whether the ground will carry it. This decides whether the job is possible at all.
Lift and set aside
Units come off in order with the machine and are laid out where they can be reached again without moving twice.
Rebuild the bearing
The base under the bottom course is rebuilt and compacted, and drainage goes in behind, because stone this heavy punishes a soft bearing.
Re-set to a string line
Units go back to line and level with the machine, bedded rather than dropped, so the finished face reads straight from every angle.
Weight And Height
Big stone does not make an engineer unnecessary
There is an assumption that armour stone holds a grade by sheer mass and therefore needs less care. It does resist sliding better than a small block, but the same municipal height thresholds apply and the same drainage rules do too.
Above about a metre we ask for a drawing here exactly as we would for segmental block. See how wall rebuilding handles the same threshold, what wall repair costs come to by face foot, and how grading and slope is set behind a wall.
No. Individual units run to several hundred kilograms, so a machine is required and the access route decides whether the work can be done at all.
Then the honest options are leaving it as it is or rebuilding that section in a smaller product. We would rather say that at the estimate than on the day.
Usually the bearing under the bottom course, because the weight punishes any soft spot, or saturated fill behind pushing individual units out of line.
Yes, exactly as a block wall does. Mass resists sliding but it does not stop saturated soil loading the wall or freezing behind it every winter.
Roughly $120 to $250 per running foot depending on unit size, height and access, since the machine time and the route are most of the variable.
Against it yes, roots in the joints no. Anything that will push a woody root between two stones buys you a leaning wall in ten years, so we suggest keeping shrubs a little back and letting perennials do the softening.
