Glossary

The model that comfort temperature rises with outdoor temperature as occupants adapt clothing and expectation. Basis of IMAC. Introduced in Lesson 0.2.

The controls a building gives occupants to regulate their own comfort — openable windows, ceiling fans, clothing freedom, air movement. Without it, the adaptive comfort band collapses to the static one.

One of five NBC/SP 41 categories — hot-dry, warm-humid, composite, temperate, cold — defined by mean monthly temperature and humidity. The first classification any Indian design depends on.

The rate of heat a building must remove to hold a target indoor temperature. Every passive strategy in the course exists to shrink it before any machine is sized.

The difference between daily maximum and minimum temperature. Large in deserts (enables night flushing), small on humid coasts.

The fraction by which a wall reduces the amplitude of the outdoor temperature swing as it passes inside. f = 0.3 means a 10°C swing arrives as 3°C.

India Model for Adaptive Comfort — locally derived comfort bands recognising that the Indian body tolerates a wider, warmer range than static Western models assume.

Predicted Mean Vote — Fanger's index predicting average thermal sensation on a 7-point scale. Basis of the static comfort model.

A weighted average of recent days' outdoor temperature, used as the input to the adaptive comfort relation. Captures the acclimatisation the body has built up.

The PMV/Fanger model treating comfort as a fixed ~24°C set-point regardless of season. Built from chamber tests; implies sealed, air-conditioned buildings.

A material's capacity to absorb, store and slowly release heat. A hero in hot-dry climates with big day-night swings; a liability in humid climates where nights don't cool.

The number of hours a wall delays the outdoor temperature peak from reaching the interior. Derived in Lesson 2.1.

Traditional building tuned to a specific local climate and materials. Teaches a method (respond to your sky), not a portable form.

The balance-point temperature above which cooling (or below which heating) is needed, used as the threshold for degree-day counting. India often uses ~26°C for cooling, reflecting the adaptive comfort band. Always stated explicitly.

Givoni's chart mapping a climate's temperature-humidity data onto zones of viable passive strategies.

A projecting horizontal sunshade or eaves over a window or wall, ubiquitous in Indian architecture. Sized to block the high summer sun while admitting the low winter sun.

A free building-climate analysis tool that reads an EPW weather file and plots the bioclimatic chart and design strategies automatically.

Long-term averages of temperature, humidity and rainfall (e.g. IMD's 1991–2020 tables) used to characterise a typical year rather than a single memorable one.

The annual sum of how many degrees and for how many days the outdoor temperature sits above a chosen base. Captures the whole-year cooling burden in one number.

Air driven through a space by pressure difference between a windward inlet and a leeward outlet. Needs both an aimed inlet and an escape path; an inlet alone barely ventilates.

Cumulative measure (CDD/HDD) of how far and how long outdoor temperature sits above/below a base — quantifies cooling or heating demand.

The temperature to which air must cool for its moisture to begin condensing. The trigger temperature for condensation, mould and corrosion; the gap between dry-bulb and dew point is the room evaporative cooling has to work.

A measure combining rainfall and wind that indicates how forcefully rain is driven against walls and openings, used to size overhangs and wall protection (per IS 1346 / SP 41).

The air temperature read by an ordinary thermometer, ignoring humidity. The horizontal axis of the psychrometric chart.

The strategy territories Baruch Givoni drew on the psychrometric chart — comfort, ventilation, mass, night flush, evaporative cooling, passive solar — each marking where one passive strategy can reach comfort unaided.

The annual sum of degrees and days the temperature sits below a base. Dominant only in India's cold zone and northern winters.

The vertical angle a horizontal overhang must command to shade a window at a given solar altitude. Set by the summer noon altitude for a south façade.

The seasonal flip of India's prevailing wind — moist air off the sea in the SW monsoon (Jun–Sep), dry land air the rest of the year — the subcontinent's defining climatic rhythm.

Using wind and buoyancy to move air through a building for cooling and air quality. The lead strategy for warm-humid India; effective where air movement offsets a few degrees of warmth.

A design move that achieves comfort without mechanical energy: ventilation, thermal mass, evaporative cooling, night flushing, shading or solar gain. The vocabulary of climate-responsive design.

A graph relating dry-bulb temperature, humidity, wet-bulb and dew point. Used to plot a city's comfort cloud and pick passive strategies.

A graph tying together dry-bulb, wet-bulb, relative humidity, dew point and moisture content of air. Plotting a climate on it reveals both its discomfort and the direction of its cure.

The ratio of the air's actual vapour pressure to its saturation value at that temperature, as a percentage. How 'full' the air is of moisture.

The maximum water-vapour pressure air can hold at a given temperature; rises steeply with temperature (Magnus relation). Sets the 100% RH line on the chart.

An effective outdoor temperature combining air temperature and absorbed solar radiation on a surface — what the envelope actually 'feels'.

The sun's angular height above the horizon, 0° at sunrise/sunset to 90° directly overhead. Sets how deep a horizontal overhang must be.

The sun's compass direction, conventionally measured from south. Tells you which façades the sun strikes and when through the day.

The angle between the sun's rays and the equatorial plane, swinging from +23.45° (June solstice) to −23.45° (December solstice) over the year. Drives the seasonal change in noon sun height.

The instant the sun crosses the local meridian and reaches its highest point for the day. The reference moment for sizing horizontal shading.

Buoyancy-driven airflow where warm air rises and escapes high while cooler air enters low — the wind-independent partner to cross-ventilation, detailed in Module 3.

A stereographic plot of the sun's altitude and azimuth across the day and year for a given latitude. The working drawing for all shading analysis.

A building designed to change behaviour by season — opening for ventilation in the monsoon, closing over mass in dry heat — needed wherever a composite climate scatters across several Givoni zones.

A Typical Meteorological Year file (often in EnergyPlus Weather / EPW format) giving hourly data for a representative year — the input for building-energy simulation.

The tendency of dense, paved city centres to run several degrees warmer than surrounding or airport weather stations, a gap that can distort design data if unaccounted for.

The lowest temperature reachable by evaporation alone, read from a thermometer with a wetted wick. The ceiling on evaporative cooling; above ~32°C wet-bulb the body cannot cool itself.

The driving pressure a breeze exerts across an opening, p = ½ρv² — rising with the square of wind speed, so orientation to a stronger wind matters more than enlarging the opening.

A radial diagram showing how often and how strongly wind blows from each compass direction. For monsoon India it must be read by season, since the prevailing wind reverses.

How many times per hour a room's full air volume is replaced by outside air. Night flushing needs a high rate — typically 10–30 ACH — to discharge a heavy mass.

The daily rhythm of thermal mass absorbing heat through the closed day and releasing it through the open, ventilated night — the operating principle that makes mass worthwhile in hot-dry climates.

An internal open-to-sky void at the heart of a plan. In hot-dry climates it pools cool dense night air, holds daytime shade, and gives a private outdoor room — a thermal device as much as a space.

Cooling air by evaporating water into it. Effective only in dry climates where the air can absorb moisture.

Cooling air by evaporating water into it; the latent heat of vaporisation is drawn from the air as it turns liquid to vapour. Powerful in dry air, futile in humid air.

Evaporative cooling that chills a surface or secondary air stream, cooling the occupied air without adding moisture to it — useful where some humidity already exists.

A perforated stone or lattice screen that shades, admits soft glare-free daylight, allows ventilation, and gives privacy all at once. Tuned by its open-area ratio.

A screen of woven vetiver (khus) roots, wetted so that dry air evaporatively cools as it passes through — a traditional hot-dry cooling device, explored further in Lesson 2.3.

The energy (~2400 kJ/kg for water) absorbed when liquid turns to vapour without a temperature change. This is the heat evaporative cooling spends to cool the surrounding air.

Purging a building's stored daytime heat with cool night air, recharging the thermal mass for the next day. Needs a large diurnal swing.

Purging a building's heat-charged thermal mass with cool night air so it can absorb the next day's heat. The essential partner to mass in hot-dry climates; detailed in Lesson 2.4.

The proportion of a screen that is open (holes) versus solid. The single number tuning a jaali: ~25–40% typically balances airflow and daylight against glare and heat.

A secure, insect-screened vent or window that can be opened at night for cross-flow across exposed mass and closed before the day heats — the hardware that makes night flushing practical.

The characteristic depth d = √(αP/π) that a daily temperature wave reaches into a wall. Time lag and decrement both scale with wall thickness measured in these depths.

How close an evaporative cooler brings the air to the wet-bulb floor, T_out = T_db − ε(T_db − T_wb). Good direct coolers reach ε ≈ 0.7–0.9.

The fraction of the overhead sky visible from a point, set by surrounding geometry. For a courtyard, SVF ≈ W/√(W²+4H²); a low SVF means deep shade but less daylight.

The energy needed to raise unit mass of a material by one degree. High c (e.g. masonry, water) lets a material store a lot of heat, strengthening thermal mass.

The total heat a building's mass can store per degree, ρ·c·V. The larger it is, the more night ventilation is needed to discharge it fully.

How quickly a material conducts heat relative to how much it stores, α = k/(ρc). Low diffusivity (dense, high-capacity materials) gives long time lag and small decrement — the basis of thermal mass.

The rate cool air carries heat out of a space, P = ρ·(nV/3600)·c·ΔT, rising with both air change rate and the indoor–outdoor temperature gap.

Density times specific heat (ρc) — how much heat a unit volume stores per degree. The true measure of a material's mass-effect, since a dense high-c material stores the most.

The gap between dry-bulb and wet-bulb temperature; the total cooling an evaporative device can draw on. Above ~10°C it is a strong strategy; under ~5°C it is futile.

The thin film of warm, humid air the body generates around itself. Moving air strips it away, letting sweat evaporate — which is how ventilation cools the person even when room temperature is unchanged.

Assemblies that allow water vapour to diffuse out rather than trapping it, helping warm-humid buildings dry and avoid hidden mould — the opposite of a sealed, vapour-trapping wall.

A roof with a reflective, high-SRI surface that bounces solar radiation away rather than absorbing it, cutting the heat reaching the space below — high-leverage in the tropics.

Rain blown horizontally by wind so it strikes walls and openings rather than falling vertically. The dramatic water threat of the monsoon, shed by deep overhangs and protected openings.

The combined aperture of openings in series, 1/A_eff² = 1/A₁² + 1/A₂², dominated by the smaller opening. It governs total ventilation flow.

The windward opening where a breeze enters and the leeward opening where it escapes. Cross-ventilation needs both — a single opening cannot drive through-flow.

Low-mass envelope (timber, bamboo, thin panels, light frame) that holds little heat and responds almost immediately to outdoor temperature — the warm-humid counterpart to hot-dry thermal mass.

The surface relative humidity (~80%) above which, sustained over time, mould will grow. No liquid water or leak is required — only persistently high surface humidity.

How far an eave or verandah extends to shade a wall, P = h/tan(β). Sized to the lowest useful sun angle for year-round tropical shade, and checked against the driving-rain angle.

Lifting the living level on a plinth or stilts to catch faster breeze, escape damp ground and re-radiated heat, and clear floods and pests — a defining warm-humid move.

The release of stored heat from a warm surface back into a space. On warm-humid nights, heated mass re-radiates into bedrooms exactly when occupants want to sleep.

A plan one room deep, so every room has openings on two opposite sides for cross-ventilation. The organising principle of warm-humid houses like the Kerala nalukettu.

A measure of how well a surface reflects solar radiation and stays cool. High-SRI (light, reflective) roofs and walls are key to warm-humid envelopes.

Buoyancy-driven air movement: warm air rises and escapes high, drawing cooler air in low. Drives ventilation in warm-humid design.

The vertical distance between a low inlet and a high outlet. Greater stack height increases buoyancy-driven flow on windless days, Δp = ρg·h·(ΔT/T).

The relative humidity of the air right at a surface. Because a cooler surface raises local RH for the same moisture, mould grows wherever surface RH exceeds ~80% — the cold spots, not the room as a whole.

The roughness factor in the power-law wind profile: ~0.14 open country, ~0.22 suburban, ~0.33 dense urban or forest. Rougher ground means a steeper profile and slower surface wind.

A path of higher conductivity (an uninsulated lintel, beam or junction) that creates a locally cold surface, raising surface RH and inviting condensation and mould.

A roof with an air gap or ventilated attic between a reflective outer layer and the ceiling, so airflow carries away absorbed solar heat before it reaches the room.

A roofed, open-sided space wrapping a building. In warm-humid design it shades the whole envelope, intercepts driving rain, and stays open to the breeze — the humid house's counterpart to the dry house's courtyard.

The increase of wind speed with height above ground, v(z)=v_ref(z/z_ref)^α. Surface friction slows air near the ground, so a raised floor catches a faster, steadier breeze.

A climate that passes through several distinct seasons — hot-dry, warm-humid and sometimes cold — across one year, as in Delhi, Lucknow and Nagpur. It demands a switching building rather than a single fixed strategy.

Putting insulation outside the mass so the mass faces the room, not the weather — deciding whether mass tracks indoor or outdoor temperature.

A central element — typically a courtyard — around which a building's plan, ventilation and seasonal-use zoning are organised, acting as its climate engine.

Thermal mass placed inside the insulated envelope (party walls, cores, courtyard walls) so it couples to the controlled indoor air and stabilises temperature rather than storing outdoor heat.

Thermal mass treated as a switchable subsystem via shading, ventilation and coupling controls — charged only when useful (winter sun, cool-night storage) and isolated otherwise.

The absorption of heat by thermal mass, dominated by solar radiation on a sun-struck surface (q = α·I). Shading the surface cuts charging five- to ten-fold, regardless of how much mass is present.

The degree to which a building's elements (windows, vents, shutters, shades) can be opened, closed and adjusted by occupants — the core enabler of a switching building.

How far a horizontal shade extends to fully shade a window of height H at the summer noon altitude: P = H/tan(β_s). Sized to the local latitude's solstice angles.

Using different parts of a building by season — a shaded cool core in summer, sunny rooms and terraces in winter, cross-ventilated spaces in the monsoon. A traditional composite-climate practice.

Thermal mass placed, shaded and controlled so it stores heat or coolness only in the seasons that reward it and stays inert otherwise — the composite-climate resolution of the mass paradox.

The fraction of solar radiation striking a window that passes through as heat. Lower SHGC suits hot, sun-exposed or west-facing glass; higher where winter solar gain is wanted.

The noon sun heights at summer and winter solstice, β = 90−|φ∓23.45°|. Their large difference lets one courtyard exclude the high summer sun yet admit the low winter sun.

A space shaped to admit and capture the low winter sun, warming the surrounding mass and rooms. The composite courtyard's winter role.

The moderate upland climate of cities like Bengaluru and Pune — mild much of the year with cooler periods, needing light seasonal switching rather than extreme strategies.

A removable cloth or awning drawn over a courtyard's open top for the hottest weeks and removed in cooler seasons — seasonal adjustability layered onto fixed geometry.

Projecting vertical shading elements that block low east/west sun, which horizontal overhangs cannot — the right device for the hard-to-shade morning and evening sun.

The proportion of a façade that is glazed. Modest WWR limits heat gain and loss; ECBC sets limits. Enough for light and air, not a heat hole.

A courtyard proportioned and detailed so a single fixed geometry performs in every season — cool well in summer, stack-ventilation chimney in the monsoon, sun-trap in winter.

A dark, exposed, sun-struck interior surface (stone or concrete floor, masonry wall) that converts incoming sunlight to stored heat. A beam on a rug warms only the rug; on dark stone it charges a thermal store.

A building shape with minimal exposed surface for its volume (cube, clustered, shared-wall), minimising heat loss in cold climates — the opposite of the breeze-seeking warm-humid plan.

Passive heating where sunlight enters through south glazing, strikes interior surfaces, and is absorbed as heat directly in the living space — the simplest and first cold-climate strategy.

The trapping of solar heat behind glass: short-wave sunlight passes in and is absorbed, but the resulting long-wave heat is held by the glazing, charging a Trombe wall or sunspace far hotter than open air.

A low-conductivity material that traps still air to slow heat flow through the envelope. Distinct from thermal mass: insulation resists heat escape; mass stores heat.

Insulated shutters or heavy curtains drawn over glazing at night to stop the day's captured solar heat leaking out through the glass during the long cold hours.

The traditional Ladakhi timber-framed glazed south balcony that captures the winter sun — a vernacular direct-gain solar collector.

Turning a building's major façade and largest glazing to true south to harvest the low winter sun, while minimising openings on the cold north, east and west — the building leaning toward the sun.

A glazed south-facing room that captures solar heat in a large volume, serving as a warm winter living space, a thermal buffer for the house, and a solar collector — closeable at night so it doesn't drain heat.

The ratio of a building's heat-losing exposed surface to its heat-holding volume. Low is best in cold climates; a compact cube or clustered form loses heat far slower than a spread-out one with wings.

A conductive path (uninsulated junction, beam, lintel) that lets heat bypass the insulation; in cold climates these and air leakage can dominate real heat loss.

A space (such as a sunspace) placed on the cold side of a house to intercept heat loss and moderate the indoor environment — a heated layer between the living space and the freezing outdoors.

A mass wall (such as a Trombe wall) sized to absorb solar heat and release it on a deliberate time delay, scheduling warmth to arrive when it is most needed.

A south-facing glazed mass wall that captures winter solar gain and releases it indoors after dark. A cold-climate workhorse.

Glass coloured through its body, which lowers SHGC and VLT together (poor selectivity) and absorbs solar heat that it then re-radiates inward — it dims a room without properly cooling it.

A bare heavy roof slab that absorbs the day's intense solar load and re-radiates it downward into the top-floor rooms in the evening — the time-lag problem (2.1) turned against the occupant, driven by the building's largest solar load.

A second, lightweight, often ventilated layer (pergola, raised tiles, PV array, second roof) above the structural slab that intercepts and sheds the sun before it reaches the roof, with an air gap to carry heat away.

Energy Conservation Building Code — India's mandatory energy standard for larger buildings, with envelope, lighting and HVAC requirements.

India's Energy Conservation Building Code for Residential buildings, launched by the Bureau of Energy Efficiency in 2018. Part I sets minimum building-envelope performance: ventilation, daylight, roof U-value and the RETV/cold-U envelope limit.

Soil and planting over a waterproofed slab that cools by three mechanisms at once — shading, insulation and evaporative cooling — while managing rainwater, cutting the heat island and giving back green space.

VLT divided by SHGC — how well a glass separates daylight from heat. Clear glass ~1.07, body-tint <1, spectrally-selective low-E ~2+. Higher is better for a hot, bright climate.

Insulation placed above the structural roof slab (under the waterproofing and screed), which keeps the slab's mass coupled to the interior and avoids interstitial condensation — the preferred way to insulate an Indian RCC roof.

A prescriptive code fixes individual component values (e.g. a wall U-value); a performance code (like the RETV path) caps an overall outcome, letting the designer trade components freely to meet it.

The principle that thermal resistances of layers in series simply add, so the total R is the sum of all layers plus the surface films; U = 1/R_total.

The net heat-gain rate over the cooling season through the envelope (excluding roof) per m², combining wall conduction, window conduction and solar gain through glazing. Capped at 15 W/m² for the four hot/temperate zones.

The principle that because the roof receives the most solar load of any surface, all day, unshaded, treating it (insulate + reflect + shade) is the single highest-value envelope intervention in an Indian building.

The Eco-Niwas Samhita's single universal prescriptive limit: roof thermal transmittance U_roof ≤ 1.2 W/m²K in every climate zone — the code's recognition that the roof is the priority everywhere.

Solar Heat Gain Coefficient — fraction of solar radiation a glazing admits as heat. Critical for hot-climate window selection.

The fraction of incident sunlight a surface reflects rather than absorbs (0–1). A dark roof ~0.05–0.15; a cool white roof ~0.7–0.8. The primary lever of a cool roof.

Glass with a low-E coating tuned to transmit visible light while reflecting near-infrared heat, achieving a low SHGC with a high VLT — the hot-climate ideal that breaks the light-vs-heat trade-off.

The small fixed thermal resistance of the still air clinging to a surface (R_si ≈ 0.13 inside, R_so ≈ 0.04 outside for walls), added to the layer resistances in a U-value calculation.

A material property: how readily it conducts heat (W/mK). Low k (insulation ~0.035) resists heat; high k (concrete ~1.8) conducts it. R = L/k.

A surface's ability to shed absorbed heat as infrared radiation (0–1). High emittance keeps a roof cooler by radiating heat back to the sky; a cool roof needs high emittance as well as high reflectance.

How strongly a layer opposes heat flow, R = L/k (thickness over conductivity), in m²K/W. Layer resistances in series add up to the wall's total resistance.

Thermal transmittance (W/m²K) — rate of heat flow through an assembly. Lower is more insulating. Built up from layer resistances in Lesson 6.1.

The fraction of visible daylight a glazing transmits (0–1). High VLT keeps a room bright and cuts electric lighting; distinct from SHGC, which governs heat.

The specific sequence of layers making up a wall. Specified by both its U-value (total resistance) and its layer order (which decides how the mass behaves).

The minimum ratio of openable window area to floor area required for natural ventilation under the ENS — highest in Warm-Humid (16.66%), lowest in Cold (8.33%).

The fraction of a façade that is glazed. In hot zones kept modest (rarely above a third), concentrated on south/north; oversizing adds heat and glare faster than useful daylight.

Window-to-Wall Ratio — glazed area as a fraction of façade. ECBC caps it because glass is the weakest thermal link.

The single question that settles whether thermal mass helps: mass only earns its place if the climate gives a period (a cool night or a warm sunny day) whose temperature it can store and release later. No such period (humid coast) = mass is a liability.

In humid climates where sweat won't evaporate in still air, moving air is the primary passive relief: a ~1 m/s breeze can add ~2–3°C of felt cooling by speeding skin evaporation. Ventilation is the air-conditioning.

The course's deepest principle, made vivid by Hubballi vs Kochi: there is no universally good wall or strategy — the right building is reasoned from the specific site's sky, so the same method yields opposite forms in different climates.

A repeatable five-step procedure to design for any site: (1) read the climate, (2) classify and derive the brief, (3) sequence the big moves, (4) quantify and check against the code, (5) cross-check the vernacular. The course distilled into a portable method.

The seven convictions underneath the techniques: no universally good building; read before you draw; the vernacular was usually right; mass/glass/breeze/sun are tools the climate values; comfort by nature beats comfort by machine; quantify to be honest; make it a habit.

The failure mode of applying a canned climate-type answer without reading the actual site — producing buildings climate-responsive on paper but poor in practice, because climate types are summaries and real plots vary by microclimate, altitude and setting.

A home for a high cold-desert climate (e.g. Leh): south-facing, compact, heavily insulated and sealed, with large south glazing, internal mass/Trombe wall and a sunspace — designed to capture the winter sun and hold its heat against frigid nights.

The principle that a building should be liveable through passive design before any mechanical heating/cooling is switched on — machines as the exception, not the crutch. The lifetime energy difference is decided largely at design stage.

A house designed to switch behaviour across a three-season composite year — defending against dry summer heat, shedding monsoon humidity and rain, and opening to the mild winter — with one fixed plan.

The order in which passive moves are made — orientation → courtyard → ventilation → mass → shading → roof/glazing → rain/damp — because later choices depend on earlier ones. Order matters as much as the choices.

The fact that a building's decades of energy use are mostly locked in during its few weeks of design, giving the designer — early, cheaply, with a pencil — outsized power over whether it will be comfortable by nature or only by machine.

Sizing windows by orientation rather than uniformly: in a cold sunny climate, large on the south to harvest winter sun and small on the north/east/west which only lose heat. The cold-climate window rule — chase the sun on one face, defend on the others.

The practice of resolving all climate strategies together into one building, sequenced so each decision (orientation, courtyard, ventilation, mass, shading, roof, detailing) supports the next — as opposed to optimising a single feature.

The traditional warm-humid Kerala house — light timber frame, steep tiled roof with deep eaves, verandahs on all sides, raised floor — a climate solution arrived at over centuries that the course derives from physics.

In a climate with no cool night (warm-humid coast), thermal mass cannot discharge and becomes a permanent low-grade night-radiator — the same wall that cools a high-diurnal-swing site cooks a coastal one. The night decides.

Designing so the building fabric and form carry the great majority of the comfort load, leaving mechanical cooling/heating as an occasional supplement rather than a permanent necessity.

Climate-responsive design sustained not as a checklist consulted for 'green' projects but as a reflex performed on every project — reading the sky before drawing, even on the rushed, unglamorous, un-'sustainable' job. The measure of whether the learning took.

The course's distilled maxim: the climate is the first input to any design, not an afterthought — because a good building is an answer to its sky, and there is no universally right answer, only the one right for this place.

The first design act: characterising a site's climate (here Hubballi's three composite seasons) to derive the brief that drives every subsequent decision.

The questions every climate design answers: is the enemy heat/cold/wet (and seasonal)? what must the building do? is there a period to store mass for? air in or out? sun in or out? how much water to shed? Each hard call collapses to one of these.

The inseparable two-part cold-climate strategy: aggressively capture solar gain (south glazing, mass) AND ruthlessly conserve it (insulation, airtightness, night insulation). Gain is wasted without retention; the two only work together.

The final audit step: comparing a reasoned design against how buildings were traditionally made on that exact site. Agreement confirms the strategy; disagreement is a flag to investigate, since the vernacular usually encodes centuries of climatic trial and error.

A home for a hot, humid, low-swing coastal climate (e.g. Kochi): lightweight, raised, open and breeze-catching, with deep shade and a steep rain-shedding roof. The photographic negative of the mass-based composite/hot-dry house.