Terraced Backyard Ideas: Tier Math, Wall Spacing and 11 Designs
Plan terraces like a builder: walls from the total drop, tier depths, the 2× setback rule and drainage between tiers, plus 11 terraced backyard ideas.
Most terraced backyard ideas start with a photo of neat stone tiers and skip the numbers that made them work. Before you turn a hill into a terraced yard, you need three answers: how far your yard drops, how many walls that takes, and how deep each level ends up once walls, steps and drainage are in.
Below is the math our crews use, a worked example and 11 terrace ideas with the heights and spacing that make them last. Not sure terraces suit your hill? Start with our sloped backyard ideas.
Quick answer
Divide the total drop by the wall height you want: a 6 ft drop is two 3 ft walls or three 2 ft walls. Set each upper wall back at least twice the lower wall’s full height, buried course included, and drain every wall. Walls over 4 ft, or with heavy loads above, need an engineer.
Terrace math: how many walls and how deep each tier
Measure the total drop and the run (the horizontal distance) with a string, a line level and a tape, then work out five numbers:
- Walls = total drop ÷ wall height. A 6 ft drop takes two 3 ft walls or three 2 ft walls.
- Levels = walls + 1. Two walls give you three flat levels.
- Tier depth ≈ run ÷ levels, minus about 1 ft per wall for the block. You can split it unevenly: more for the patio tier, less for planting.
- Setback check: each upper wall sits at least 2× the lower wall’s full height (buried course included) behind it.
- Steps = tier drop ÷ 6 in. risers, with one fewer tread than risers. At 14 in. treads, a 3 ft change takes 6 risers and about 6 ft of run; a 2 ft change takes 4 risers and about 3½ ft.
Why the 2× setback rule matters
Soil behind a wall pushes on it, and so does anything sitting on that soil. Allan Block’s article on terraced retaining walls gives the common rule of thumb: a wall’s zone of influence extends horizontally about twice its height, and an upper wall inside it adds surcharge load to the wall below. Too close, and the pair behaves like one tall wall neither was built to be. Even with the spacing met, Allan Block notes, overall slope stability may still need an engineer’s analysis.
Rule of thumb: If the math leaves any tier shallower than twice the height of the wall below it, switch to lower walls or fewer levels, or bring in an engineer. Squeezed tiers, usually from enlarging one level or stacking planting shelves a foot or two apart, are how terraces end up acting like one tall wall.
Planning terraced walls?
Central PA: we build them. Anywhere else: get the whole yard planned.
In Clinton, Lycoming, Centre and Union counties we build retaining walls at a fixed price in writing, from $6,900 installed, 33% down, never more. Anywhere else, the Groundwork Build-Ready plan ($1,795) gives you everything in Full Yard (a scaled site plan and planting list, a dimensioned hardscape sheet and a grading and drainage concept) plus construction details and a quantity takeoff.
Worked example: two 3 ft walls or three 2 ft walls?
Two 3 ft walls give fewer, deeper levels that suit a dining patio or a lawn. Three 2 ft walls give more, shallower tiers for planting, but add a leveling pad, drain line and flight of steps, and a stack of three walls gets an engineer’s review.
Say your yard drops 6 ft over 40 ft from the house to the back fence, a 15% slope, and the walls run 50 ft across the yard.
| Factor | Option A: two 3 ft walls | Option B: three 2 ft walls |
|---|---|---|
| Flat levels | 3 | 4 |
| Tier depth, split evenly | About 13 ft (12 ft usable) | 10 ft (9 ft usable) |
| 2× setback needed (buried course counts) | 7 ft, met | 5 ft, met |
| Steps between tiers | 6 risers, about 6 ft of run | 4 risers, about 3½ ft of run |
| Wall face, incl. 6 in. buried course | About 350 sq ft | About 375 sq ft |
| Leveling pads, drain lines, cap rows | 2 of each | 3 of each |
| Geogrid | Often not needed in decent soil; check the block maker’s chart | Rarely needed |
| Engineer needed if | Anything heavy sits within 7 ft above a wall | Always, since three terraces need an engineer’s review; also anything heavy within 5 ft above a wall |
| Best for | A dining patio or a lawn you’ll use | Beds and vegetable tiers |
The costs land closer than you’d think: about the same block either way, but three walls add a third leveling pad, drain line, row of caps and flight of steps, while 3 ft walls can need geogrid on clay or under a slope. Take Option A if a level must hold a dining table (you want about 3 ft behind every chair); take Option B for planting tiers, knowing a stack of three walls gets an engineer’s review. A hybrid works too: one 3 ft wall under the patio and two 18 in. walls for the beds, though as a stack of three walls it gets the same engineer’s review as Option B.
Only need one flat area instead of several tiers? Our guide to landscaping and leveling a sloped backyard shows how to work out the cut and fill, and when the edges of a level patch need a wall.
What each tier can hold
Give every tier one job and size it for that job:
| Tier use | Usable depth | Plan for |
|---|---|---|
| Dining patio | 12 ft or more | One step below the door; no hot tub unless the wall below is engineered |
| Lawn | 10 ft or more | A mower route: a side ramp or gate |
| Fire pit circle | 14 to 18 ft | A seat wall on the uphill side |
| Vegetable garden | 6 to 7 ft | A 3 to 4 ft bed you can reach across, plus a 3 ft path |
| Planting beds | 3 to 4 ft | Shrubs and perennials; trees well back from the wall below |
Terraced backyard ideas that work
These terraced backyard landscaping ideas assume segmental block walls unless noted; our retaining wall ideas compare other materials.
Picking the block for your tiers? Our best interlocking retaining wall blocks compared guide covers Allan Block, Versa-Lok, Keystone, Belgard and Fortus.
1. A patio terrace off the back door
Make the top tier the patio, one step (6 to 7 in.) below the door and pitched about ¼ in. per ft away from the house and toward one end, so water leaves at a corner instead of sheeting over the wall below. Treat a 3 ft drop at the patio edge like a deck edge: a planter, hedge or railing keeps chairs from backing off it.
2. Lawn terraces
Stepped lawn panels read clean and open. Give the mower a route (a side ramp or gate, since mowers don’t do steps), and run a flush paver mow strip along the top of each wall so you’re not scalping grass or chipping caps.
3. A terraced backyard garden for vegetables
A south-facing slope terraced into beds warms early and drains well. Fill beds with at least 12 in. of good topsoil and run water to every level; hauling a hose up three flights gets old fast.
4. Seat-wall terraces
Around a patio or fire pit, build the tier walls at 18 to 20 in. with a deep cap and they double as seating. That’s lower than a typical 2 ft tier on purpose: at 24 in., most people’s feet dangle.
5. Planted terraces with steps through the middle
Set the steps into the wall line so they don’t eat tier depth, and match risers to the block course where you can, since 6 in. block makes 6 in. risers easy. Keep every riser in a flight the same height.
6. Curved block terraces
Curves soften a terraced backyard and follow the land. With setback block, each course on an outside curve sits on a slightly tighter radius, so lay out the bottom course larger than the block maker’s minimum or the top course won’t fit.
7. Boulder terraces
Boulder tiers suit wooded or natural yards. Keep each tier to about 2 to 3 ft, set the bottom row partly buried on compacted stone, tilt every boulder back into the hill and pack drainage stone behind. Taller boulder walls need an engineer and an operator who has set them before.
8. Timber terraces
Treated timber is the cheapest, most DIY-friendly terrace and the shortest-lived. Use ground-contact lumber (UC4A or UC4B on the tag), treat every cut end, use hot-dip galvanized or stainless fasteners and keep tiers to about 2 ft, adding deadmen (tie-backs buried in the slope) on anything taller. Even built well, it’s usually the first terrace material you’ll replace.
9. Small terraced backyard ideas
In a small yard, two tiers usually beat three, because every wall and stair takes space. Keep walls 12 to 24 in., give one level to seating and one to planting, and let the walls curve so the tiers read deeper than they are.
10. Steep terraced backyard ideas
Run the same math on 6 ft of drop over 15 ft (a 40% slope): split evenly, three levels come out about 5 ft deep, short of the 7 ft that 3 ft walls need once the buried course counts, and four levels under 4 ft, short again for 2 ft walls. On steep ground, spacing caps how many flat levels you get. Allan Block also cites a flat bench of at least 5 ft in front of any wall built on sloping ground as common practice, so build one or two usable levels and plant the rest.
11. A terraced backyard with a pool
A pool is a heavy load: water alone weighs about 62 lb per cubic foot. Any terrace wall with the pool inside its zone of influence needs an engineer, and pool builders generally want the shell in cut, undisturbed soil, not new fill. Set the pool level first and terrace around it.
Tiered and terraced patio ideas
A tiered patio splits one paved area into two or three levels, and a terraced patio is the paved tier of a terraced yard. Both are built from the same parts: steps, seat walls and retaining walls, with every level pitched to drain on its own. Three layouts cover most yards:
| Layout | Level change | What takes up the drop | Watch for |
|---|---|---|---|
| Two-level patio: dining up top, lounge or fire pit below | 1 to 3 risers (about 6 to 20 in.) | Full-width steps, or an 18 to 20 in. seat wall along the upper level’s edge | Pitch each level about ¼ in. per ft to its own low corner so water doesn’t sheet down the steps |
| Raised patio off the door, steps down to the yard | Up to about 3 ft at the outer edge | A block retaining wall with drainage stone behind it and geogrid where the block maker’s chart calls for it | A planter, hedge or railing along the edge; steps set into the wall line |
| Patio tier above planting tiers | One 2 to 3 ft wall under the patio, 18 in. to 2 ft walls below it | Two or three walls, each set back at least 2× the height of the wall below | A stack of three walls gets an engineer’s review |
Size each level from the tier table above: 12 ft or more for a dining level, 14 to 18 ft for a fire pit circle. On a raised paver patio we built in Dunnstown, near Lock Haven, the block wall under the patio went in with geogrid reinforcement and compacted stone backfill, and steps tie the patio to the deck. Pricing a patio level in central PA? See our patio cost and retaining wall cost pages.
Drainage between tiers
On a terraced backyard slope, every wall sits under the water from the tier above, and water is behind most failures of terraced backyard retaining walls (see why retaining walls fail). Each wall needs:
- 12 in. of clean drainage stone behind the block, with backfill compacted in 6 to 8 in. lifts.
- A 4 in. perforated pipe at the base. Some block makers only require it on taller or loaded walls; on terraces, we put one behind every wall.
- A solid pipe that carries each wall’s water past the bottom wall to daylight, with outlets at least every 50 ft on long walls.
- Tiers pitched about 1 to 2% toward one end, not over the wall below or back into the base of the wall above.
- Downspouts in their own solid pipe, never dumped onto a tier.
Mistake to avoid: Daylighting the upper wall’s pipe onto the tier below. That water soaks straight into the next wall’s drainage stone, and the bottom wall ends up draining the whole hill.
For more on the stone, pipe and outlets behind each tier, our retaining wall drainage guide covers drain pipe placement, outlet spacing and routing drains on terraced walls.
Sample plan 03 puts it together. It first drains a low addition with 4 in. perforated pipe in a fabric-wrapped stone trench on three sides at 1% minimum fall and a solid outlet about 40 ft down the side slope to daylight. Then the slope behind it becomes two 2 ft terraces: two walls of about 60 ft, each with three exposed courses plus a cap, one buried course, a stone pad, and clean stone and perforated pipe behind it tied into that same outlet.
The upper wall sits 6 ft back, more than twice the lower wall’s full height even counting the buried course, so the tiers act independently with margin. The plan reuses 12 to 14 boulders from the site and keeps the excess soil on site. Our online backyard design service draws plans like this, and online retaining wall design is the place to start when walls are the main event.
See the whole terraced garden and French drain plan, from the drain around the addition to the two 2 ft garden terraces, swales and boulders.
Tiered retaining walls: spacing, height and when to call an engineer
The 2× rule is the starting point, not the whole rule. The Concrete Masonry & Hardscapes Association (CMHA) puts it this way: for each terrace to act on its own, the distance between walls must be at least twice the height of the lower wall. Closer than that, the design treats the stack as one taller wall carrying the load of the wall above it. Three details decide if your tiers really qualify.
- Count the buried course. CMHA measures wall height from the top of the leveling pad to the top of the highest block, not counting the cap, so the part below grade counts. A wall that shows 3 ft above a 6 in. buried course is 3½ ft tall, and the next wall belongs at least 7 ft back, not 6.
- Keep the upper wall the same height or shorter. Allan Block’s terracing guide pairs the 2× spacing with an upper wall no taller than the lower one.
- Set the upper wall on solid ground. Upper walls often land on soil churned up during the dig. Allan Block says to remove it down to solid ground and put it back compacted: wall rock in 8 in. lifts, or on-site soil in lifts of 4 in. or less. Skip that and the upper wall settles.
Allan Block’s commercial installation manual says an engineer must evaluate terraced walls that need geogrid, walls closer than twice the lower wall’s height, retaining walls with more than two terraces, and terraces with any structure above them. That third trigger matters for planting terraces: a stack of three walls, like Option B in the worked example, gets an engineer’s look even when each wall is short. The residential guide adds slopes above or below the walls, groundwater, surcharges and bad soils to the list.
Under IRC R404.4, a wall that needs engineering has to be designed against overturning, sliding, excessive foundation pressure and water uplift, with a safety factor of 1.5 against sliding and overturning. On terraces the engineer also checks global stability: the whole slope moving behind and beneath every wall at once. CMHA says that check belongs in every design, and Allan Block says the lower walls in tiers that don’t act independently must be designed to carry the upper walls.
Terraced backyard cost and DIY limits
What drives terraced backyard cost
Most of the cost follows the wall face: length × (exposed height + buried course), about 350 to 375 sq ft in the worked example. Ask installers to price per face square foot and your bids line up. Prices vary a lot by region, and these drive them:
- Access: if a skid steer can’t reach the slope, every block and ton of stone moves by hand.
- Soil: balanced cut and fill stays on site; hauling out or trucking in adds up fast.
- Material: timber ($), segmental block ($$), natural stone and boulders ($$ to $$$), poured concrete ($$$).
- Steps and drainage: every flight and outlet line is its own small job.
- Engineering and permits for tall or loaded walls.
DIY terraced backyard: where the line is
DIY is realistic for tiers of 2 ft or less in standard wall block, with nothing heavy above and room to get material close. Hire a builder as walls approach 3 ft, on wet clay or with tight access. Bring in a licensed engineer for walls holding back more than 48 in. of soil, or more than 24 in. with a driveway, pool, structure or upper wall loading them (IRC R404.4). Groundwork plans lay out terraces and drainage, but they aren’t sealed engineering drawings.
Permits vary by town. The model code exempts walls up to 4 ft measured from the bottom of the footing unless they support a surcharge (IRC R105.2), so a wall showing 3 ft above ground can reach 4 ft once you count the buried course and base. Our guide to retaining wall design covers block choice, base depth and geogrid.
Common terracing mistakes
- Tiers inside the 2× zone. Planting shelves stacked a foot or two apart act as one tall wall.
- No route between levels. Plan how the mower, wheelbarrow and garden cart reach every tier.
- Heavy loads on a tier. Hot tubs, sheds and parking need an engineered wall below them.
- Odd steps. Divide each tier drop evenly, with no short step at the top or bottom.
- Digging before the locate. Call 811 a few business days ahead. It’s free.
Related: our retaining walls guide gathers our articles on wall design, drainage and cost in one place.
Building this in central PA? We build terraced walls with the 2x setback, a drain behind each tier and outlets that skip the wall below. See how we build a retaining wall in Lock Haven or a retaining wall in Williamsport (the same crew covers South Williamsport, Loyalsock and Montoursville). In Centre County, see how we build a retaining wall in State College.
Common questions about terraced backyards
How far apart should terraced retaining walls be?
Set each upper wall back at least twice the height of the wall below, measured horizontally, and count the buried course in that height: about 7 ft for a 3 ft wall on a 6 in. buried course, 5 ft for a 2 ft wall. Any closer and the pair has to be designed as one wall, usually by an engineer.
How deep should each terrace be?
Divide the run by the number of levels and subtract about 1 ft per wall. Plan at least 10 to 12 ft for a patio or lawn, 6 to 7 ft for vegetables and 3 to 4 ft for planting beds, and never less than twice the height of the wall below.
How much does a terraced backyard cost?
Most of the cost follows the wall face: total length times height, including the buried course. Access, soil hauling, material, steps, drainage and engineering drive the rest, and prices vary a lot by region, so ask for bids priced per face square foot.
Can I build a terraced backyard myself?
Tiers of 2 ft or less in standard wall block, with good access and nothing heavy above, are reasonable DIY projects. Walls near 3 ft, wet clay or tight access call for a builder, and walls over 4 ft, or over 2 ft with a load above, need a licensed engineer.
Can you put a pool in a terraced backyard?
Yes, with an engineer. Water weighs about 62 lb per cubic foot, so walls near the pool carry real load, and pool builders generally want the shell in undisturbed soil rather than new fill. Set the pool level first and terrace around it.
What is the cheapest way to terrace a backyard?
Treated timber tiers of about 2 ft, built with ground-contact lumber (UC4A or UC4B on the tag), cost the least and are the easiest to DIY, but they are also the shortest-lived. Balancing cut and fill so the soil stays on site keeps hauling costs down with any material.
How tall should each terrace wall be?
We usually build backyard terrace walls about 2 to 3 ft tall. Tiers of 2 ft or less are realistic DIY, Allan Block pairs the 2× spacing with an upper wall no taller than the one below it, and walls holding back more than 48 in. of soil need an engineer under IRC R404.4.
Do terrace walls need drainage?
Yes. Every tier sits under the water from the tier above, so each wall needs 12 in. of clean drainage stone, a 4 in. perforated pipe at the base and a solid pipe that carries the water past the bottom wall to daylight, not onto the tier below.
Is my slope too steep to terrace?
Usually not, but steep ground limits how many levels fit. Each tier must be at least twice as deep as the lower wall is tall, and Allan Block cites a flat bench of at least 5 ft in front of a wall on sloping ground, so on a 40% slope plan one or two usable levels and plant the rest.
Sources: CMHA, SRW FAQ on terraced walls; Allan Block, terraced retaining walls; Allan Block, residential terracing guide; Allan Block, commercial installation manual: terraces; IRC R404.4, retaining walls; Call 811.
Groundwork Design Co. · designed by builders
Get your terraces drawn before you dig
A Full Yard plan ($895) gives you a scaled site plan and planting list, a dimensioned hardscape sheet and a grading and drainage concept. Build-Ready ($1,795) adds construction details and a quantity takeoff. Designed remotely from photos and measurements, anywhere in the U.S.; single areas start at $349.
See design packagesSee sample plans
Building in central Pennsylvania? Our crews build this work around Lock Haven, Williamsport and State College, retaining walls around Williamsport.
Published by Muthler Landscaping & Construction, owned by Thayne Muthler (PA HIC #PA212584). How we research and check facts: editorial policy.