Ñande Roga

Ñande Roga — "Our House" in Guaraní — is a repeatable housing series, not a building: a fixed kit of parts, a designation, a product line of dwelling for the Paraguayan urban edge. It adopts the grammar of the Soviet housing series — fixed bay, cross-wall plan, panel nomenclature, assembly as scheduled event — and re-founds it in local material and local hands: confined clay brick, prestressed clay-block floors, stabilized earth, and a rationed quantity of concrete.

A heavy, repeatable housing machine in Paraguayan clay — Soviet in its grammar, Guaraní in its ground — that shades deeply, breathes freely, and can one day be taken apart into the bricks it was born from.

Phase I delivers 480 dwellings (~33,000 m² residential GFA) on 2.5–4 ha at the urban edge of Greater Asunción: three 5-storey bars and one 8-storey portal slab, every dwelling double-aspect, shaded by a 2.0–2.4 m galería, raised on a 1.5 m loma plinth. The performance claim is falsifiable — ≥ 90% of occupied hours in adaptive comfort on passive strategies alone — gated on simulation, a mockup cell, and one full year of post-occupancy measurement.

The search image is a 2.5–4 ha urban-edge parcel in Greater Asunción's expansion belt (Luque, Capiatá, Mariano Roque Alonso, Lambaré fringe): flat to gently sloping (0.5–3%), alluvial silty-clay with a wet-season water table at 0.8–2.5 m, above the five-year flood line, long axis available E–W, open to the northeast breeze, with a trunk bus corridor on one edge and school and health post within 800 m. Clear tenure, grid electricity and piped water at the boundary are prerequisites; absence of sewer is assumed and designed for. High water table and termite pressure are generators, not objections: no basements, shallow footings, ventilated timber, funded inspection.

Phase I places three 100 m E–W bars (B1–B3, 5 storeys, 360 dwellings) and one 8-storey N–S portal slab (B4, 120 dwellings) whose gable — the Guaraní relief mural in projected brickwork — faces the bus street. Dwelling faces inward; monument faces out. N–S calles de viento between the bars funnel the prevailing breeze into two ~100 × 38 m courtyard gardens, which keep 20+ m of winter noon sun against the 16 m bar shadow. A plaza with the preserved timbó canopy, fútbol court and tereré tables sits at the portal; a ~1,200 m² retention lagunita occupies the low west corner, deliberately downwind of intake air. Coverage ≈ 17% · FAR ≈ 1.0 (headroom to 1.6) · 133 dwellings/ha net · ~450 inhabitants/ha. Full build-out: a mikrorayon of ~1,400 dwellings in three phases around a school-and-park spine.

Every level is reachable dry-foot in the rain — plinth, portal and galería form one covered line. The motorcycle is the primary vehicle of the Paraguayan working household: 1.2–1.5 per unit → 600–700 covered bays in the plinth arcades and two moto patios. Cars get their honest minority share — 0.3–0.35 per unit → ~160 edge-field surface bays in porous rubble pavers under trellis, never in the courtyards, 10% EV conduits. ~480 bicycle racks; bus stop ≤ 200 m from every gate; remise and moto-taxi rank at the portal. The internal loop is a shared-surface calle tranquila at 20 km/h, pedestrian priority on the plinth. No garage: buried parking for 480 units would cost more than the blokera, the guardería and the lagunita together — and we choose the places people live in.

Baseline: 35–38 °C summer maxima at 70–85% RH · ~1,400 mm/yr with 80–100 mm/h cloudbursts · mild winter (11–13 °C means, surazos to 5–8 °C) · NE prevailing breeze. At 25.3°S the north facades are the sun side, the south facades the cool side. Bars run long-axis E–W; large glazing never faces the rising or setting sun. The 2.0–2.4 m recess is a fixed solar instrument: summer noon sun at 88° — fully shaded; equinox 64.7° — 1.3 m ray run, short of the recess; June solstice 41.3° — a 0.7–1.1 m sun band enters and warms the brick floor exactly when wanted. ~95% of annual beam hours are blocked from north glass; free winter gain is admitted. Wing walls deflect the oblique NE breeze; the portal slab wears the celosía against low E/W sun; the bars mass to the SW against the surazo.

Cross walls (~350 kJ/m²K, 6–8 h lag) and rammed-earth commons (~500 kJ/m²K, 8–10 h lag, hygric buffering) stand exposed behind lime finishes; slab soffits are exposed — suspended ceilings are banned in living areas; roof insulation sits outside the slab. 25–30 t of cycled material per unit absorb 20–30 kWh per diurnal swing, flattening a 12–14 °C outdoor swing to ~4 °C indoors. Every unit is double-aspect with ribbon openings ≥ 5% of floor area per aspect and fixed brick-louvre vents over the doorheads: cross-flow ≥ 20 ACH on breeze days. Brick shafts (0.6 × 1.2 m, one per two bays) extract kitchen and bath air at source, ≥ 40 L/s per dwelling; the night purge ≥ 8 ACH recharges the mass with courtyard air 1–2 °C cooler than street air.

The bar section is itself the overhang — driving-rain exposure on glazing is near zero. Humidity is controlled by source extraction, breathable monolithic walls and ventilated cavities; mold is an airflow-geometry problem, not a dehumidifier problem. Continuous ribbon bands with splayed lime-washed reveals target a 3–5% daylight factor in living rooms and daylight autonomy to dusk; no decorative exterior lighting — the building is a shadow in the evening.

Roof yield ≈ 8,400 m³/yr against ≈ 8,700 m³/yr non-potable demand — near parity. Gate: WUFI transient runs of every build-up — surface RH < 80% for ≥ 95% of hours. Verification: EnergyPlus + CFD for the courtyard and calle-de-viento field, and twenty instrumented units through one full year before the claim publishes as measured.

Transverse confined-masonry cross walls (230 mm 18-hole clay brick, f'm ≥ 8 MPa) at 3.9 m centres, confined by 180 mm cast-in-place tie columns and bond beams at every floor; one-way prestressed-joist and clay-bovedilla floors spanning 3.9 m with a 45 mm topping; cross walls acting as shear walls in both directions. The 8-storey portal slab switches to an RC frame with brick infill bracing the lower two stories — honest engineering at Paraguay's seismicity. Material ration per m² GFA: concrete ≤ 0.16 m³ · steel ≤ 22 kg · brick ≈ 120 units.

All precast elements weigh ≤ 2.0 t — liftable by a single 12 t mobile crane; no tower crane exists in the program. Every panel derives from one 3.9 × 1.35 m half-storey mold cell: one formwork family with bolt-in inserts produces the entire facade catalog. Each part number is optimized once (FE layout, joist spacing, tie section) and repeated ~4,000 times across the quarter — savings come from series multiplication, exactly the Soviet logic. 30% recycled brick aggregate in non-structural mixes; excavation reused in rammed walls.

Foundations — no basements, no deep piles by default: 400 mm recycled-brick rubble trench footings under every loadbearing wall (capillary break, drainage blanket and circularity in one element); 1.5 m confined-masonry plinth piers at 3.9 m centres carrying ground beams; a ventilated rubble crawl, never sealed. Under the 8-storey portal only, geotech-gated options: vibro-rubble columns or 1.5–2 m over-excavation with lime-stabilized backfill on a stiff ground-beam grid.

The bar reads as a 6.7 : 1 hull — ≈ 100 × 11.6 m, 15.0 m to coping, 17.5 m with stacks and tank band. The bay is a near-√2 rectangle (3.9 × 2.7 m); recess depths (2.0 / 2.4 m) and plinth height (1.5 m) all derive from it. The north face is a continuous shadow band interrupted by board-marked slab-edge fascias — five datum lines per elevation, no more; living bays notch 0.4 m deeper than bedroom bays — variation without decoration. The south face opens in wider ribbon bands toward the courtyard; gables are blind brick terminations with celosía screens to the stairs. The building's window is its shadow.

Wall depth at openings ≈ 480 mm plus 2.0 m of shadow. Three brick tones in horizontal strata like a cut riverbank; no paint on brick. Residents own the trellis and reveal layer; rail, soffit, fascia and brick are inviolable. South spandrels are zoned for moss and fern colonization from year 5. The 1.5 m plinth is a rusticated rubble-concrete arcade — moto and bicycle storage, bodegas, lavaderos, kiosco, cooperative depot — open and inspectable, nothing sealed; its deck is a continuous raised walk, dry-foot in any storm, with brick stoops up to the galería and steps and ramps to the street at ≤ 25 m intervals. Two stair-lift cores project 0.9 m as south-face brick buttresses, daylit through celosía, discharging directly onto the galería — the galería is the corridor; no internal public corridor exists anywhere in the bar.

Stepped 2% roofs drain to oversized internal gutters with twin scuppers; each unit's water tank docks on precast saddles aligned over its shaft — the tank band as disciplined cornice. Skyline inventory fixed by design: nothing on the roof that is not also a load, a duct, or a gutter.

Industrialize the vernacular: Paraguay's advantage is brick hands, a mature prestressed-joist industry, national cement and kilns everywhere — not panel factories. Off-site (≈ 25–30% of labor hours): facade panels cast face-down with brick slips pre-laid in the mold, precast stairs, shafts, gutters and cisterns, pressed stabilized-earth blocks; joists are procured from existing prestressing yards. On-site: hand-laid confined walls, slab assembly, rammed-earth commons. The plant is a 2,000 m² yard on site with one casting bed and one mold family; transport is 50–300 m flatbed moves on the future calle tranquila; buffer stock 7 days per type; storm protocol Oct–Mar — casting under shed, maturity method absorbs cure interruptions.

Three bars and the portal run in staggered pairs over ~60–70 weeks with a peak workforce of ~100, including 20% apprentices from the future resident body — the yard is the district's first payroll. Quality control adopts Soviet geodesy and ОТК discipline: closed survey loops, plinth level ±10 mm over 100 m, panel ±5 mm, a frozen reference type-bay per bar, maturity-gated strikes, panels stamped with part number and cast date, non-conformance charged to the yard, not the crew. A mockup cell and one prototype bay must pass a full wet season before series production.

The saving exists only at series multiplication — ≥ 3 bars, the molds must pay for themselves — and the maintenance advantage accrues over decades, not at handover. The claim is falsifiable by design: the prototype carries the cost model before a single production brick is laid.

Collectivity must be load-bearing — in program, budget and maintenance clocks — or it fails; that is the Robin Hood Gardens lesson. Here it is functional: the lavadero, the clay oven, ~70 huerta plots, the blokera and the vivero are shared labor with shared product, administered by a resident cooperative with a real budget and a contractual maintenance doctrine. Each household personalizes its own 2.2 m galería bay — identity without fences; the geometric supervision of 300+ galerías over guardería, court and plaza replaces surveillance with daylight. The unit mix is family-weighted (20% one-bed / 45% two-bed / 35% three-bed); every dwelling double-aspect, no single-aspect plan anywhere in the series.

Series multiplication delivers ≈ US$ 540–680/m² against a regional conventional baseline of US$ 700–850/m² — 18–25% below — with a 35–40% program shortening and earlier cooperative income. The construction year is the first social program: the yard is the first payroll, its apprenticeship the first school. Both the cost claim and the comfort claim stand or fall on the prototype and the monitoring year.