Hubballi: A Composite-Climate Home

Hubballi sits on the Deccan plateau at about 650 m, an elevation that tempers its heat, and its year splits cleanly into three seasons — the textbook composite signature.

From March to May it is hot-dry, peaking near 36 degrees C in April: hot days, but cooler plateau nights and a real diurnal swing. From June to October the monsoon arrives — about 900 mm of rain, 70 to 80 percent humidity, overcast and muggy; temperatures actually drop to around 26 degrees C, but the air turns heavy. From November to February it is mild and pleasant, dry and sunny with cool nights near 16 degrees C — the easy season, when you mostly just open up.

That reading gives our brief straight from nature: defend against dry heat in summer, shed humidity and rain in the monsoon, and stay open and gently warm in winter. Three jobs, one house. This is the switching building of Module 4 — no single fixed strategy will do.

The client brief: a family of four with joint-family visits common; a 2BHK of about 110 m2 with living and dining, kitchen, pooja niche, two beds, two baths and a terrace; a 9 by 18 m plot with its long axis roughly north-south, road on the south; a modest budget, passive-first, comfortable year-round without habitual AC.

Each move follows from the last; orientation sets up the courtyard, which organises the plan, which decides where mass and glass go.

First, orientation. We run the long axis east-west so the main rooms face north and south, and we keep west glass to a minimum — that single decision buys both summer sun control and a little winter gain (Lessons 1.1 and 4.4). Second, a central courtyard becomes the organising void at the heart of the plan: a year-round mediator that performs differently in each of the three seasons (Lesson 4.2). Third, we drive cross-ventilation through every room toward that court, so the plan answers both monsoon humidity and the summer night flush (Lessons 3.1 and 2.4).

The order matters more than it looks. Get orientation wrong and no glazing saves you; site the courtyard badly and ventilation never works. Design here is a chain of consequences, not a checklist.

With the bones set, the envelope decisions fall out in turn.

Fourth, selective mass: heavy, shaded internal walls that stay cool, paired with a lighter monsoon-exposed skin. The mass helps in the dry summer and stays harmless in the monsoon, because it is shaded and internal rather than baking in the sun (Lesson 4.3). Fifth, deep shading — chajjas over every opening, the court, and a verandah on the south and west — to exclude the high summer sun while still admitting the low winter sun (Lesson 4.4). Sixth, a cool, insulated roof plus modest, selective glazing: the roof is the worst single offender on an Indian home, so we tame it first, then add just enough good glass for daylight without heat (Lessons 6.4, 6.5, 6.3).

Nothing here is exotic. Every move is a standard element of the North Karnataka house — courtyard, chajja, verandah, terrace — now deployed deliberately and quantified. Climate-responsive design in India is less about importing technology than understanding why the old moves worked, and applying them with intent.

The seventh decision answers the monsoon directly: deep roof overhangs to throw driving rain clear of walls and openings, and a raised plinth to keep ground damp out of the floor (Lessons 3.4 and 3.2).

Now watch the one unchanging plan behave three ways. In the hot-dry summer the shaded court and chajjas keep the high sun off; thick shaded internal mass stays cool and is flushed each night by cool plateau air drawn through the court, while the cool roof rejects the worst load. In the warm-humid monsoon the court turns into a stack chimney pulling cross-ventilation through every room; the deep overhangs and raised plinth shed driving rain and ground damp, and the light monsoon skin stores no heat. In the mild winter the low sun slips under the chajjas into the south rooms and the court, and the house simply opens up — the building at rest.

One fixed plan, three behaviours, switched by the season. Module 4 realised in brick and stone on a real Hubballi plot.