The backbone of serious masonry
Concrete block — CMU, if you want the trade term — is the structural workhorse of masonry. It does not get the glory of brick or stone, but it does the heavy lifting: foundation walls, retaining walls, piers, outbuildings, and the structural core behind brick and stone veneer. When something needs to be strong, straight, and built to code, block is usually the answer.
Good block work is precise. Every course level, every wall plumb, every core that needs grout filled solid, every bar of rebar where engineering calls for it. Bad block work shows forever — a wavy wall cannot be hidden, and a weak wall cannot be fixed with paint. We lay block the way it is supposed to be laid: carefully.
What we build with block
Foundation walls are the most common: block foundations for additions, garages, porches, and outbuildings — footings below the frost line, walls laid plumb, cores filled and reinforced per plan, waterproofing before backfill. (More on our foundation masonry page.)
Retaining and garden walls in block give you a clean, structural wall that can be left exposed, painted, stuccoed, or faced with stone or brick. For walls that need real strength — tall walls, walls with heavy loads above — reinforced block is often the most economical engineered solution.
Piers and columns in block provide the structural core for brick piers, porch columns, and gate posts — built to carry the load, then faced to match the house. Outbuildings and sheds get block walls that stand up to weather and time far better than wood framing at grade.
We also build block for commercial and multi-unit work: common walls, equipment enclosures, dumpster enclosures, and site walls — the unglamorous masonry that has to be right because inspectors and engineers are watching.
Reinforcement: what separates real block work from stacked block
A block wall's strength comes from what is inside it, not just the block itself. Vertical rebar in grouted cores ties the wall to the footing and gives it bending strength against soil pressure and wind. Horizontal joint reinforcement ties courses together. Bond beams — a course of special block filled with concrete and rebar — create a continuous structural ring at the top of walls.
This is engineering, and on structural walls we build to the engineer's spec or the code's prescriptive requirements — whichever governs. A garden wall can be simple. A foundation wall or tall retaining wall cannot. We know the difference, and we do not blur it.
Waterproofing and drainage
Block is porous — water moves through it. Any block wall below grade or holding back soil gets waterproofing on the earth side and drainage at the base, before backfill. This is the step that gets skipped on cheap jobs, and it is the reason so many block basement walls seep and so many block retaining walls fail. We treat every buried block wall as a waterproofing project that happens to be made of block.
Finishes for block
Block does not have to look like block. Stucco gives a clean, traditional finish in any color. Brick or stone veneer over block gives you the premium look with block's structural strength behind it — the best of both. Paint works for utility structures. And for walls where the block itself is the finish, we lay with tight joints and consistent coursing so it looks intentional, not industrial.
Block in Northern Virginia's soil
Our clay soil is the reason block details matter so much here. Expansive clay pushes on foundation and retaining walls with every wet season, which is why reinforcement, drainage, and waterproofing are not upgrades — they are the job. A block wall in sandy soil can get away with less; a block wall in Fairfax clay cannot. We have repaired enough under-built block walls to know exactly where the shortcuts show up: missing grout in cores that should be filled, rebar skipped to save an hour, waterproofing "forgotten" before backfill. When we build your block wall, every core that engineering calls for gets filled, every bar gets placed, and the waterproofing goes on before the excavator comes back. It is more work up front and far less work later.
Matching existing block
Repairs and additions to existing block structures need matching units — block sizes and textures have changed over the decades. We source to match, and where exact matches are impossible, we blend or refinish so the new work does not clash with the old. Repointing and repair of aging block walls follows the same careful mortar matching as brick.
Our process
Step one: we visit and review your plans or your existing structure — measuring, checking soil and drainage, and understanding the structural requirements. Step two: you get a free written estimate with the wall spec, reinforcement plan, and price. Step three: we build — footings, coursing, reinforcement, grouting, and waterproofing, each stage verified. Step four: we clean up and walk the finished work with you.
Every structure is different — contact us for a free written estimate.
Call (301) 679-9193 or send the form for a free on-site estimate.