Great Zimbabwe at its peak - thriving African city with dry-stone walls, 14th century

800 years. No mortar. Still standing.

Across southern Africa, over 200 dry-stone structures survive from the 11th-15th centuries. Great Zimbabwe housed 20,000 people. The walls—some 36 feet high—were built without mortar. They're still standing today.

Precision-cut stone, carefully stacked. Gravity and friction do the work. No mortar to crack. No plaster to fail. Water sheds off; the structure endures.

Modern dry-stack brick home in Ghana - metal roof, covered veranda, warm evening light

Modern dry-stack brick. Built to last.

Great Zimbabwe's builders shaped stone by hand. The precision required master craftsmen and years of training. Our system transfers that precision to the mold. Laterite clay—abundant across Ghana—is pressed into interlocking bricks. The geometry does what the stonemason's skill once did.

Same principle. Same dry-stack technique. But now any worker can build walls that perform like master craftsmanship.

Laterite clay is everywhere in Ghana. Dig it up. Press it. Fire it or cure it. Cost per brick: 18-29 US cents. Cement block: 73-91 US cents. The material is nearly free—the labor to shape it is the cost.

Every imported bag of cement is money leaving Ghana. Every brick made from local laterite is a job, a skill, wealth that stays.

MaterialCost per UnitSource
Laterite brick18-29¢Local clay deposits
Cement block73-91¢Imported cement

Ashanti Region alone has 37 million metric tonnes of clay deposits.

Ghana's construction sector employs 420,000 people. Skilled artisan shortage: 60,000+. This system creates jobs that didn't exist:

RoleTraining TimeOpportunity
Brick press operatorDaysManufacturing job
Dry-stack masonDaysConstruction trade
Quality inspectorWeeksSupervision role
Press maintenanceWeeksTechnical trade

A trade becomes a business. A business becomes a contractor. That's how a middle class gets built.

System Feature Benefit
WallsDry-stack interlocking brickNo mortar, no plaster, no skilled masons
WallsLaterite/local clay70% wall cost reduction, jobs stay local
WallsConcave face with drip edgeWater sheds off, no penetration
CoolingDouble roof with ventilated gap5-8°C reduction
CoolingClerestory windowsHot air exits high, stack effect
CoolingDeep overhangs (chajjas)3-5°C reduction, shade
CoolingJaali screens / perforated brickAirflow + privacy + decorative
CoolingRoof mist spray (dry season)Evaporative cooling, 3-5°C
Target15°C cooler than exteriorNo AC needed
Electrical24V DC LED lightingSafer, simpler wiring, cheaper
ElectricalHand-crank generator backupAlways have light, no grid dependency
Hot WaterBlack tank passive solarWarm water, no water heater
WaterRainwater cistern + gravity feedRunning water, reduced plumbing
SanitationVented bio-toiletIndoor toilet, no smell, no septic
InternetUbiquiti mesh, 10 homes share Starlink90% cost reduction per home
InteriorJapanese shoji / bamboo screensLight, cheap, movable, family reconfigures
WindowsLouvered shutters + mosquito screenTraditional, local carpenter, full ventilation
Dry-stack brick wall showing horizontal shadow lines at each course - the signature of the system

Half the cost. Same home.

Conventional Dry-Stack System
2-Bedroom Home (80 m²) $26,500 $12,400 target
Cost per square meter $330/m² $155/m² target

Our goal: cut construction costs in half using local materials and simplified systems. Validation in progress.

Component Target Savings
Walls (no mortar, no plaster)70%
Electrical (24V system)45%
Finishes (brick is the finish)90%
Interior walls (bamboo screens)75%

The house is designed to operate with minimal external services. Passive systems replace expensive utilities.

NeedConventionalThis System
CoolingAC unit + GH¢200-400/month electricityPassive: double roof, clerestory, cross-ventilation. Cost: GH¢0
LightingGrid dependent, dark during outages24V LED + hand-crank generator. Never in the dark.
Hot waterElectric or gas water heaterBlack tank on roof. Sun heats it. Free.
WaterMunicipal connection, GH¢50-100/monthRainwater cistern + gravity feed. Backup municipal.
InternetIndividual connection, GH¢150-300/month10 homes share Starlink via Ubiquiti mesh. GH¢15-30/month.

Annual operating savings: GH¢4,500-9,000 ($280-560) compared to conventional homes.

The hand-crank generator means the family always has light. Grid goes down? Crank for a minute, lights stay on. No batteries to replace. No fuel to buy. The house works whether the grid does or not.

Exploded view of interlocking brick courses showing how blocks fit together

How it works.

Four-face interlock. Concave water shedder. Each brick locks to its neighbors on top, bottom, and both ends. The concave face creates an overhang—the course below is recessed. Water has nowhere to enter.

Patent Application: 63/955,346 (Filed January 7, 2026)

View Specification (PDF)

View Drawings (PDF)

Stretcher brick - the main wall unit with concave face and four-face interlock

The main wall unit. Concave weather face, upper rail tenon, lower rail mortise, end tenon and mortise.

Corner L brick - turns corners while maintaining interlock

Turns corners while maintaining interlock. Multiple tongues and mortises engage stretchers from both directions.

Close stack showing two courses interlocked

Courses stack with running bond offset. Each brick locks to six neighbors. The wall becomes a monolithic structure.

Vision

Extraordinary homes at reasonable prices. Built locally, by local people, with local materials. Good housing. Good jobs.

Market

Ghana's housing deficit exceeds 1.8 million units. Annual production falls short of demand.

1.8M Housing Deficit
8.2M Households
$4.6B Annual Remittances
40K Units Built/Year
Current Deficit1.8 million units
Annual Production~40,000 units
Annual Need~200,000 units
Net Annual Shortfall~160,000 units

At current production rates, the deficit grows each year.

Source: ConstructAfrica, Ghana Ministry of Works and Housing

Ghana has approximately 8.2 million households distributed across five income quintiles.

QuintileHouseholdsShare of IncomeEst. Annual Income
Q1 (Lowest 20%)1.64M4.7%~$700
Q21.64M9.6%~$1,450
Q31.64M14.8%~$2,230
Q41.64M22.3%~$3,360
Q5 (Top 20%)1.64M48.6%~$7,320

Top 10% holds 32.2% of national income.

Source: World Bank 2016

Q5 Households1.64M
Q4 Households1.64M
Upper Q3 (estimate)~800K
Total Addressable2-4 million households

Government "affordable housing" programs price units at $13,000-$42,550. These prices serve primarily Q5 households.

Source: Centre for Affordable Housing Finance in Africa

Annual Remittances$4.6 billion
Percent of GDP6.4%
Est. Housing Share25-35%
Annual Housing Flow~$1.2 billion

Building a house back home is a significant life decision for the diaspora. Platforms like Seso Global and MyAwayHome address trust and oversight challenges for remote construction.

Source: World Bank Remittance Data

Feasibility

Laterite soil is abundant across Ghana. Compressed earth blocks have been proven at scale in East Africa.

70% Mortar Reduction
400 Blocks/Day
5 Days Training
37K+ Homes Built (East Africa)
Soil TypeLaterite (iron-rich clay)
CoverageCommon across Ghana and West Africa
Current UseRoad construction, traditional building
TransportLocal sourcing reduces costs

The material is already present. No imports required.

Compressed earth blocks and interlocking stabilized soil blocks have been used in East Africa for decades.

Hydraform (South Africa)Commercial-scale production, established supply chain
ISSB Programs (Uganda, Kenya)37,000+ homes built, 150,000 people housed
Housing Microfinance$30M in loans, 76% borrowers under $10/day income
Block TypeInterlocking, dry-stack
Mortar Reduction70% less than conventional
Production400 blocks/day with manual press (3-person team)
Training5-day program

Simple operation enables community participation and creates local jobs.

Field validation in Ghana requires:

Soil TestingLocal composition analysis
EquipmentProduction equipment adaptation
ComplianceGhana building code documentation
Cost VerificationProduction scale economics

Strategy

Local partners bring local expertise. Developers license the system.

Two roles make this work:

RoleContributionOutcome
Technical PartnerLocal soil expertise, field validation, production oversightQuality assurance
DeveloperCapital, land, construction, salesLicensed production rights

The technical partner validates production for Ghana conditions. Developers build houses.

Developers license production rights for their territory.

License ComponentDescription
TerritoryExclusive or non-exclusive by region
TrainingProduction methods, quality control
EquipmentMold specifications for block production
SupportTechnical guidance during startup

License terms negotiated with qualified developers who demonstrate capacity.

StakeholderWhat They Get
Technical PartnerOngoing role, professional recognition
DeveloperProven system, competitive advantage, technical support
MarketQuality housing at reduced cost
WorkersLocal jobs, transferable skills

Everyone has aligned incentives. Success for one means success for all.

Budget

Local materials. Local labor. The economics work.

MaterialsLocally sourced laterite vs imported cement and steel
LaborCommunity workers trained on-site
TransportReduced logistics cost from local sourcing
EquipmentManual and semi-automated presses, locally serviceable

Imported materials carry shipping, duties, and currency risk. Local materials do not.

Block ProductionOn-site or near-site, eliminates transport markup
Mortar Reduction70% less than conventional masonry
Skill Requirements5-day training for production crew
ScaleEconomics improve with volume

Quality housing delivered through standard market channels. Pricing reflects market conditions.

Detailed budget available to qualified partners.

Patent

Patent-pending interlocking block with integrated water management.

An interlocking block geometry designed for dry-stack construction. The shape of each brick creates a slight overhang such that the course below is recessed, which gives water nowhere to enter.

Four-Face InterlockUpper rail tenon, lower rail mortise, end mortise, end tenon
Concave Water ShedderProfile curves inward, directs water to drip edge
Overhang/RecessEach course shelters the joint below
Block TypesStretcher, Corner L, Termination

Three mechanisms defeat water intrusion at every horizontal joint:

Capillary BreakRecess exceeds wicking threshold
Surface Tension BreakDrip edge forces water to release
Gravity DrainageConcave profile directs water outward

Water follows the concave profile, releases at the drip edge, and falls free. It cannot reach the horizontal joint because the joint is tucked back under the overhang.

U.S. ProvisionalApplication No. 63/955,346
Filing DateJanuary 7, 2026
TitleInterlocking Building Unit with Integrated Water Management Profile
InventorMichael Hoffman
Non-Provisional DeadlineJanuary 7, 2027

The invention is geometry, not material. The water-shedding profile functions through geometric principles that apply regardless of material composition.

LateriteCommon across Ghana and West Africa
Compressed Earth BlockStandard CEB and ISSB approach
ConcreteConventional block production
Fired ClayTraditional brick manufacturing
Other MaterialsAny curable or formable material

The patent covers the block shape. Use what's local.

Action Plan

Find the right technical partner. Everything else follows.

ContactPurpose
Technical PartnerField validation lead, production oversight
University ConnectionKNUST, University of Ghana - engineering faculty
DeveloperCapitalist partner with land and construction capacity
Ghana Standards AuthorityBuilding code compliance pathway
PhaseActivityOutcome
1Identify technical partnerPartnership agreement
2Soil sampling and testingMix design validation
3Block production trialsStrength verification
4Pilot constructionField validation
5Developer licensingCommercial scale-up
Partner IdentificationNear-term
Production Validation3-6 months after partnership
Pilot Construction6-12 months after validation
Commercial OperationsFollowing successful pilot

Timeline depends on finding the right partner. The rest is execution.

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