Walls are priced by face area, not length
The first thing to understand is that retaining walls are quoted per square foot of wall face, height multiplied by length, not per linear foot.
That matters because height drives cost non-linearly. A wall twice as tall needs a deeper excavation, a wider base, more drainage volume, and geogrid reinforcement extending back into the slope. Doubling height more than doubles the work.
It’s also why terracing two shorter walls often costs less than one wall of the combined height, which is a genuinely useful thing to know before you commit to a design. This is where every retaining wall conversation should start.
Typical ranges in the Tooele and Salt Lake valleys
| Scope | Typical range |
|---|---|
| Low garden or edging wall | From around $3,000 |
| Standard structural back-yard wall | $8,000 – $15,000 |
| Terraced or rural hillside work | $15,000 – $25,000+ |
| Large engineered walls | Quoted individually |
These are budgeting ranges. Your number depends on height, material, access and what’s in the ground, none of which can be assessed from a photo.
What drives the number
Height. The dominant factor, for the reasons above.
Material. Segmental block is generally most economical at typical residential heights. Boulder cost swings with stone size and machine time. Natural cut stone carries the highest labour cost because each piece is fitted individually.
Drainage. Drain rock, perforated tile, filter fabric and the outlet. A real cost and a non-negotiable one.
Reinforcement. Above certain heights, geogrid tying the wall back into the slope. This also means excavating further back, which increases both labour and backfill volume.
Excavation conditions. Rocky ground, common across Tooele County, slows digging considerably. Existing structures, utilities and mature tree roots all add time.
Access. Whether machinery and material deliveries can reach the wall line. A back yard we can drive an excavator into costs meaningfully less per square foot than one where everything comes through a gate.
Engineering. Where height or loading requires a stamped design.
Grading and finishing above and below the wall, and any planting or erosion control in the scope.
What a cheap bid is usually missing
Retaining walls are the single easiest landscape element to underbid, because the expensive parts are invisible once the job is finished.
Drain rock and drain tile. Backfilling with the soil that came out is faster and cheaper and guarantees the wall will fail. This is the most common omission.
Filter fabric. Cheap to include, and without it the drain rock silts up within a few years and stops working.
Compacted base depth. Setting the first course on undisturbed soil rather than excavating and compacting road base.
Geogrid. Leaving out reinforcement the height calls for, along with the deeper excavation it requires.
Any of those makes a bid look competitive and makes the wall a future problem. Ask each contractor to walk you through what’s going behind the wall, and read up on how retaining wall drainage works first so you know what a good answer sounds like. The answers separate them quickly.
How to compare bids properly
Ask for the square footage of wall face each bidder is quoting, then divide. If one bid is dramatically lower per square foot for the same wall, something structural is missing from it. That’s not a bargain, it’s a different product.
Getting your number
The variables that move retaining wall cost most, actual height needed, ground conditions and access, all require standing on the site.
Our on-site estimate is free and comes back itemized: excavation, base, materials, drainage, reinforcement and labour priced separately. That lets you see where the money goes, adjust the design if you want to, and compare meaningfully against other bids.
Get a free estimate and we’ll walk the slope with you before quoting anything.