Pro Center · Architects · Engineers · GCs · AHJs
The technical documentation library: ICC-ES AC447 acceptance criteria, full IBC/IRC code compliance with seismic zones A through E, UL fire testing, Envion® composite material specs, CAD details, and architect/engineer resources. If a detail you need isn't here, email info@blokusa.com.
The headline numbers every architect, engineer, GC, and code official asks first. Pull this card into your spec book.
| Property | Value | Notes |
|---|---|---|
| Material | Envion® composite | Proprietary blend; base is 100% recycled polypropylene |
| Standard block weight | ~6.2 lbs | ~90% lighter than a conventional 8″ CMU (~38 lbs) |
| Standard block size | 16″ × 8″ × 8″ | Cut-line increments every 3″ |
| Internal channels | ~1.5″ Ø | Horizontal + vertical — fits Greenfield / Romex |
| Color (default) | Charcoal gray | UV-stabilized via integral carbon black |
| Custom color | Any | Truckload-quantity minimum |
| Connection method | Mortarless, interlocking | Dovetail + post/receiver geometry; no glue, no nails |
| Tensioning | Post-tension rod | Footer/slab → top plate, full-height vertical compression |
| Build speed vs. wood | ~50% faster | Side-by-side time-to-shell comparison |
| Build speed vs. CMU | ~80% faster | No mortar cure time, no specialized labor |
| Design strength vs. CMU | 10× stronger | Capacity-design comparison per AC447 protocol |
| Tools required | Rubber mallet | No mixers, no specialty masonry tools |
| Field-modifiable | Yes | Cuts cleanly with standard saws at 3″ marks |
| Recyclable | 100% | Base polymer (PP) is recyclable; all jobsite scrap reusable |
| LEED | Eligible | Recycled-content + waste-reduction credits |
All numbers above are from internal R&D and the AC447 testing protocol. Project-specific stamped engineering supersedes general specs — request the latest design guide for your jurisdiction.
Lok-N-Blok was tested by independent labs against the same acceptance criteria your AHJ uses. The opinion letters are part of the design-guide package — request the full set below.
Full acceptance-criteria testing performed by Wiss Janney Elstner Associates. Lok-N-Blok meets current National Building Code requirements (IBC / IRC), including all seismic code requirements for zones A through E. Opinion letters available in the technical documents library.
A full range of fire-performance tests was performed at UL's laboratories in Northbrook, IL. Detailed results are in the Lok-N-Blok Design Guide & Technical Manual. Spec-book ready for any inspector who asks.
Because Lok-N-Blok meets all requirements of the National Building Code, it carries the same insurability profile as wood-frame and conventional masonry construction. No special endorsement required for typical residential or commercial coverage.
Envion®'s base polymer is polypropylene, the most environmentally friendly of fossil-based plastics. Heat-resistant; if burned, emits only water vapor and CO₂ — no toxic off-gassing. Different from PVC and many other plastics in this regard.
A Lok-N-Blok wall is three things: an interlocking dry-stack, a vertical post-tensioning system, and a top-plate / roof-tie-down assembly that you already know how to build.
Each block carries integral dovetails on both faces and posts/receivers on top and bottom. Blocks lock horizontally and vertically as you stack. Corners are formed by the same dovetails — no specialty corner block needed; perpendicular walls interlock through the standard geometry.
Steel rods run vertically from the footer or slab through the full wall height to the top plate. Once the wall is dry-stacked, the rods are tensioned — every block is compressed against the rest, every interlock is pulled tight. This is what holds the wall to the foundation and resists uplift.
A standard top plate sits on the wall, secured by the post-tensioning system. Standard roof trusses set atop and tie to the top plate — exactly how you already do it. Conventional methods, conventional tools.
The questions every contractor asks before quoting their first Lok-N-Blok job. Full FAQ at /faq.html; full Design Guide on request.
Designed to cut at 3-inch increments. Built-in cut lines mark where to part. For rough openings (windows, doors), you can cut at any point — no degradation to structural integrity. Standard blade cuts cleanly.
Each block has integral cavities ~1½″ in diameter running both horizontally and vertically through the body. Greenfield or Romex runs through these channels. Brought out anywhere by drilling through the side.
Sheetrock, panel, or wood finish nails / screws / glues directly to the block. Higher holding strength than pine lumber. No stud searching: the entire wall is solid attachment. Cabinetry no longer needs pre-blocking before sheetrock.
Same as conventional masonry — nails, screws, adhesives, mechanical fasteners. Lok-N-Blok accepts every standard exterior cladding.
Leave the rough opening when stacking; insert the unit and facially attach via the nailing flange. Same as wood-frame or steel-stud construction.
Post-tensioning rods anchor into the footer or slab and run vertical through the full wall height. Final torque pulls the entire wall down onto the foundation and compresses every interlock simultaneously.
Capable of any climate — hurricane (FL/Gulf), wildfire (CA/CO), seismic (CA/PNW/AK), arctic (cold-soaked), arid (desert UV), tropical (humidity + termites). Concrete-class performance with a polymer base that doesn't rot, rust, or feed insects.
Designed primarily for structural exterior walls, but nothing prohibits interior use. Single SKU + interlocking geometry simplifies the project bill of materials dramatically.
Every building type Lok-N-Blok is designed for. Each has corresponding code-compliance documentation in the design guide.
What the wall does once it's standing. The 11 properties most relevant to AHJs, insurers, and homeowners.
UL flame-spread + smoke-development tested. Won't ignite, won't feed fire.
Composite polymer doesn't absorb water. No swelling, no rot path.
Multiple-times capacity vs. CMU under stamped engineering.
No organic substrate for mold to grow on.
~6.2 lbs per block · ~90% lighter than 8″ CMU.
Carbon-black integral stabilization. No sun-degradation.
100% recycled feedstock + 100% recyclable end-of-life.
No food source for termites, ants, or microbial growth.
Mass + internal cavities provide STC-class performance.
Stack heights not limited by mortar-cure cycle.
Cuts, drills, and fastens on-site with standard tools.
Six folks who saw the product before mass-market launch. Industry roles span design/build, plastics manufacturing, architecture, education, and homeowners.
My background in the building industry, design, and sales all allow me to see the huge potential and game-changing ability of this product.
Obviously, you have built something with Lok-N-Blok. I do believe that this would be an excellent product for waterfront properties or areas that are prone to flooding.
Looks promising in the South Florida environment, where everything else rots or rusts.
Your block (Lok-N-Blok) is going to be the most disruptive technology this industry has ever seen.
Being able to do most of the construction ourselves would save a considerable amount of money. Your product appears to be a perfect alternative to the planned cinder block walls for these buildings.
Your block (Lok-N-Blok) is going to be the most disruptive technology this industry has ever seen.
Lok-N-Blok wasn't built in a hackathon. The interlocking-geometry thesis dates to 1996. The product you can buy today is the result of three decades of iteration on geometry, material chemistry, and tooling.
Full PDF design guide includes: stamped structural details, AC447 opinion letters, UL fire reports, cut-line drawings, corner geometry, foundation tie-in details, MEP routing, roof attachment, finish-cladding interfaces, and rough-opening dimensions.
As details and drawings are produced for new customer projects, they're added to the technical-documents library. If a specific detail you need isn't in the package yet, email info@blokusa.com with the requirement — the engineering team turns most requests inside two business days.
Real Three.js scene with real Lok-N-Blok dimensions. Stack a wall, drop in doors and windows, see the live cost & weight.