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WonderAncient heating fact

A hypocaust was the Roman system of underfloor heating: a furnace sent hot air under a floor raised on small pillars and, in some buildings, up through hollow walls. It warmed baths and wealthy homes.

Vitruvius, De architectura, Book V

EngineeringArchitectureTechnologyHistory

The story behind the card

The name comes from Greek words meaning 'heated from below'. Under the floor stood rows of small brick or stone pillars, called pilae, and a furnace outside the room pushed hot air and smoke into this low space; hollow box tiles set into the walls could carry the heat upwards and out. Roman writers credited a wealthy businessman of the early 1st century BCE, Sergius Orata, with inventing heated 'hanging baths', but historians doubt he was the first to warm floors this way. The architect Vitruvius described how to build such baths late in the 1st century BCE, and the system spread across the empire, from Britain to North Africa. Keeping it going took a steady supply of fuel and enslaved workers or servants to tend the fires.

Türkçe oku
Hipokaust, Romalıların yerden ısıtma sistemiydi: bir ocak, küçük ayaklar üzerine oturtulmuş zeminin altına sıcak hava gönderir, bazı yapılarda bu hava duvarlardaki boşluklardan da yükselirdi. Böylece hamamlar ve varlıklı evler ısınırdı.
Vitruvius, De architectura, 5. kitap

Adı, Yunanca “alttan ısıtılan” anlamındaki sözcüklerden gelir. Zeminin altında, pilae denen küçük tuğla ya da taş ayaklar sıra sıra dizilirdi; odanın dışındaki bir ocak sıcak havayı ve dumanı bu alçak boşluğa gönderirdi. Duvarlara yerleştirilen içi boş kutu tuğlalar ise ısıyı yukarı taşıyıp dışarı atardı. Romalı yazarlar, MÖ 1. yüzyılın başlarında yaşamış varlıklı bir iş insanı olan Sergius Orata'yı ısıtmalı “asma hamamların” mucidi sayar; ama tarihçiler, zemini bu yolla ısıtan ilk kişinin o olduğundan şüphelidir. Mimar Vitruvius, MÖ 1. yüzyılın sonlarında böyle hamamların nasıl yapılacağını anlattı; sistem Britanya'dan Kuzey Afrika'ya kadar imparatorluğun her yanına yayıldı. Ateşi sürekli yanık tutmak için bol yakıt ve bu işi yapan köleler ya da hizmetkârlar gerekiyordu.

Sources and further reading

Background reading: Hypocaust
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