Six builds, one working system

Catch it, settle it, filter it, store it. Each step removes a different problem, so skipping one leaves you treating water that is still dirty.

What you end up with: Roughly 1 000 L of stored rain and 20 – 40 L/day of drinking water that has been filtered and disinfected.

1. 1Split Bamboo Rainwater GutterGet the roof water into one place before you build anything to hold it.$5 – $30 for poles, wire and a collection drum · Half a day
2. 2Rooftop Rainwater Harvesting with First-Flush DiverterThrow away the dirtiest 20 L of every storm — the cheapest water treatment there is.$90 – $300 depending on tank size and gutter run · 1 – 2 days
3. 3Ferrocement Water Storage TankStorage is what turns a wet season into a dry-season supply.$150 – $350 for a 5,000 L tank · 5 – 7 days including curing
4. 4Folded Cloth Pre-FilterTake out silt so the slow filter's sand does not clog in a week.Under $3 for cloth and a tie · 20 minutes
5. 5Concrete Biosand Water FilterThe workhorse: removes turbidity and most pathogens with no consumables.$25 – $75 depending on cement and mould access · 1 day to cast, 7 days to cure, 3 weeks for the biolayer to mature
6. 6Safe Water Storage VesselA filtered bucket recontaminates in a day if the storage vessel has no tap.$5 – $20 per vessel · 1 hour per vessel

Burn less, burn cleaner, then stop burning for part of the cooking. Done in this order each build reduces the fuel the next one needs.

What you end up with: Typically 40 – 60% less fuel per meal and no visible smoke in the cooking space.

1. 1Insulated Brick Rocket StoveInsulated combustion is the single biggest fuel saving available.$8 – $20, or free from reclaimed brick and clay · Half a day, plus drying time for mortar
2. 2Retained-Heat Basket CookerBeans and maize finish off the fire — half the fuel for long-cooking food.$5 – $15 from local cloth and dry filling · Half a day
3. 3Plywood Solar Box CookerOn clear days lunch costs nothing at all.$25 – $70 depending on glazing and foil · 1 – 2 days
4. 4Waste Paper & Leaf BriquettesFree fuel from waste paper for the stove you just built.Under $15 for a tin mould, a drum and a rack · 1 day to set up, 2 weeks to first dry fuel
5. 5Raised Biomass Drying RackWet fuel is smoky fuel; drying is what makes briquettes and wood burn clean.$10 – $60 in poles, mesh and roofing offcuts · 1 day

The full briquette chain — the deep version of this path, with binder ratios and output numbers, lives on the briquettes hub.

What you end up with: A press line producing 100 – 300 briquettes a day from material collected free.

1. 1Cone Pit Biochar KilnChar the woody residue that will not press wet.Free as a dug pit; $80 – $250 for a steel cone · 1 day to dig; 3 – 5 hours per burn
2. 2Lee Hite Eco-Briquette Lever PressThe lever press is the step from household to small business.$25 – $90 in timber, pipe and hardware · 2 days to build, then continuous production
3. 3Lever-Arm Charcoal Briquette PressCharcoal dust is the highest-value feedstock in most towns.$35 – $80 in timber, steel pipe and fasteners · 1 – 2 days to build; 300 – 500 briquettes per day by hand
4. 4Raised Biomass Drying RackTwo to three weeks of drying decides whether the briquettes sell or mould.$10 – $60 in poles, mesh and roofing offcuts · 1 day
5. 5TLUD Gasifier StoveA stove that suits fines and briquettes, so you can demonstrate the fuel.$5 – $25 from scrap tins · 3 – 4 hours

Containment, ventilation, handwashing, then reuse. The handwashing station matters as much as the pit — it is what breaks the transmission route.

What you end up with: One ventilated toilet, two handwashing points and a greywater bed for the washing area.

1. 1Arborloo Shallow-Pit Compost ToiletThe cheapest safe start: shallow pit, moved and planted when full.$25 – $70 for a reusable slab and light superstructure · 1 – 2 days per relocation
2. 2Ventilated Improved Pit LatrineThe permanent version once you can cast a slab — the vent kills the smell and flies.$200 – $600 depending on lining and superstructure · 1 – 2 weeks
3. 3Tippy Tap Handwashing StationHands-free water at the toilet door, buildable in an afternoon.Under $5, often free from scrap · 1 hour
4. 4Foot-Pedal Handwashing StationThe durable version for a school, clinic or busy compound.$8 – $35 for the frame, container and linkage · Half a day
5. 5Greywater Reed BedStops washing water pooling and breeding mosquitoes.$50 – $200 for a household bed · 2 – 4 days

Hold water in the soil first, then irrigate what is left. Irrigating unimproved soil wastes most of what you carry.

What you end up with: A garden that feeds a household through the dry season on 40 – 80 L of water a day.

1. 1Zai Pits and Stone Contour BundsCatch and hold rain in the ground before you spend anything on pipe.Under $20 — an A-frame level and hand tools · Dry-season work: roughly 60 – 100 pits per person per day
2. 2Keyhole Garden with Central Compost BasketConcentrates compost and water into a bed you can reach without treading.$0 – $20 using stone, scrap timber and household waste · 1 – 2 days to build; productive within a season
3. 3Vermicompost Bin from Stacked CratesCompost is what makes the soil hold the water you add.$10 – $30, less with salvaged crates · Half a day to build; first castings in 8 – 12 weeks
4. 4Gravity Drip Irrigation from a Raised BarrelGravity drip puts water at the root, not on the leaf.$30 – $90 depending on drip tape and drum price · Half a day
5. 5Buried Clay Pot (Olla) IrrigationFor the driest beds — buried pots lose almost nothing to evaporation.$1 – $3 per pot; 10 – 20 pots for a family plot · Half a day to install a bed
6. 6Shade Net Nursery TunnelSeedlings raised under shade transplant through heat that kills direct-sown crops.$30 – $120 for netting, poles and wire · 1 – 2 days

Most earth walls fail at the bottom or the top, not in the middle. This sequence does the plinth and the roof-line protection properly.

What you end up with: A single-storey earth wall on a stone plinth, rendered and roofed to survive the rains.

1. 1Stone Masonry Plinth & FoundationEarth walls need 300 mm of stone between them and the ground water.$30 – $150 depending on how far the stone travels · 3 – 6 days for a small building
2. 2Soil-Cement Floor SlabDo the floor while the site is still open.$90 – $250 for a 20 m² room · 2 days to lay, 7 days moist curing
3. 3Sun-Dried Adobe Brick YardLearn the soil with hand-moulded bricks before you invest in a press.$10 – $20 for moulds; bricks cost soil and labour · 1 day to build moulds, 400 – 600 bricks/day with four people, 3 weeks curing
4. 4Manual Compressed Earth Block PressThe pressed block is the step up in strength, speed and finish.$30 – $60 in materials · 2 – 3 days to build, then ~300 blocks/day with three people
5. 5Lime and Earth Plaster for Earthen WallsBreathable render protects the wall without trapping moisture in it.$40 – $90 per small house of lime and sand · 2 – 3 days per coat, with a week between coats
6. 6Bamboo Truss Roof FrameA wide overhang is the real waterproofing on any earth wall.$90 – $300 for a small building, mostly treatment and fixings · 1 week including treatment soak, 2 days to erect