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Build Like a Roman
Roman Lime, Mortar, and Concrete
In this episode, the Build Like A Roman Podcast episode looks at the Roman use of Lime mortars, Pozzolans, a volcanic ash which modified the nature of lime, and how they produced concrete.
The focus on this episode is lime from calcium based limestone. We'll look at limes derived from Dolomitic and Magnesium in the future. There deserve their own episode, given the difference between them and calcium limes. For one, they need vastly extended slaking time compared to calcium to avoid post construction expansion and other problems.
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The Episodes definitions:
Opus signinum = Hydraulic flooring/render with crushed pottery in lime binder. Key in baths and water features; related to opus signinum.
Opus Caementicium = Concrete (lime + aggregate)
Binder – The cementitious component that coats and glues aggregate grains, hardening by chemical reaction and/or carbonation.
Mortar – A plastic mix (binder + aggregate + water, sometimes additives) used for bedding and pointing masonry; hardens to a rigid, adhesive matrix.
Plaster – As a noun, a finishing material for interior (and sometimes exterior) surfaces; as a verb, the act of applying a plaster/render coat.
Stucco / Render – Historically imprecise. Can be lime-, gypsum- or cement‑based; composition and regional usage vary
Lime - Non-hydraulic lime (Air lime): Produced by burning relatively pure limestones. Sets slowly by carbonation. Common in Europe, Middle East, and India until the late 19th century.
Lime - Hydraulic lime (Water lime): Produced from impure limestones containing clay/silica. Hardens under water. Widely used in Roman and later European construction.
Gypsum - Used for internal plasters and decorative finishes. Rapid setting but not durable in damp conditions.
Portland Cement
- Patented in 1824 (Joseph Aspdin, Leeds).
- By late 19th century, became dominant due to strength and speed of setting.
- Conservation issue: often too rigid and dense compared to historic lime mortars, leading to damage in traditional masonry.
Sands
- Siliceous sands: durable, sharp, but chemically inert.
- Calcareous sands: softer, more chemically compatible with lime binders, but less durable.
- Volcanic sands: reactive, good pozzolanic properties.
Plasticity – Ability to undergo permanent deformation without cracking
For students of archaeology, history, and art history — and for
anyone interested in how ancient buildings actually came into being.
North Africa and Western Asia are home to a multitude of Roman
buildings. Some still used on a daily basis, others in ruins, but that's
typically not the fault of the original builders. The fact that these still
exist at all after 2,000 years or more is a testament to skill and creativity
of the original builders.
There are some great Podcast which look at Roman politics,
history, and architecture, however in this Podcast, we focus on Construction
history, that being building materials, techniques and and the people who did
the work!
From structures to frescos, we'll cover it all!
Hosted by Darren McLean.
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10. Roman Glass - Sand, Soda, and Empire
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9. Lath, Reed, and Wattle - Roman Walls and Ceilings
20:52||Season 1, Ep. 9Want to know what a 'Party wall' actually is? Give this a listen.This week, the Build Like a Roman Podcast is looking at Roman Wattle and Daub, Opus Craticium. A building style that was probably for more widespread than we'd think.☕ Buy Me a Coffee - https://ko-fi.com/buildlikearomanPhotos for this episode on Instagram: https://www.instagram.com/p/DWBM5Ftl46c/This Episode's Translations:Opus Caementicium – Roman concreteOpus Craticium – Timber-frame wall with wattle or lath and plasterCraticii – Woven branch framework (wattle)Harundo – Reed used for lathingAssulae / Asseres – Wooden lath stripsTector – PlastererTrulla – Plasterer’s trowelTrullissatio – First coat of plasterFaber Tignarius – CarpenterParies Communis – Party wall (shared wall)Ambitus – Passage between neighbouring housesInsula – Roman apartment buildingPartire – “To divide,” origin of the word party in party wallFor students of archaeology, history, and art history — and foranyone interested in how ancient buildings actually came into being.North Africa and Western Asia are home to a multitude of Romanbuildings. Some still used on a daily basis, others in ruins, but that'stypically not the fault of the original builders. The fact that these stillexist at all after 2,000 years or more is a testament to skill and creativityof the original builders.There are some great Podcast which look at Roman politics,history, and architecture, however in this Podcast, we focus on Constructionhistory, that being building materials, techniques and and the people who didthe work!From structures to frescos, we'll cover it all!Hosted by Darren McLean.ktwsba7h
8. Roman Plumbing - More than Aqueducts
23:52||Season 1, Ep. 8This week, the Build Like a Roman Podcast is about Roman plumbing, from the infrastructure to the delivery of it and the materials used.☕ Buy Me a Coffee - https://ko-fi.com/buildlikearomanPhotos of this episode: https://www.instagram.com/p/DVycL_zl1zl/This Episodes Translations:Aquaeductus = water pipe or water tubeCloaca Maxima = Great SewerCurator Aquarum = Water commissionerLibratores = Surveyoraqua sub pressione = Pressure engineeringcastellum aquae divisorium = water distribution terminalquinaria = A measurement of waterFurtum aquae = Water theftVitium = a fault, defect, or point of illegal tampering in the systemPlumbum = LeadAes = BronzeTubuli fictiles = Terracotta pipesRedemptor = a type of combined contractor, and project managerFor students of archaeology, history, and art history — and foranyone interested in how ancient buildings actually came into being.North Africa and Western Asia are home to a multitude of Romanbuildings. Some still used on a daily basis, others in ruins, but that'stypically not the fault of the original builders. The fact that these stillexist at all after 2,000 years or more is a testament to skill and creativityof the original builders.There are some great Podcast which look at Roman politics,history, and architecture, however in this Podcast, we focus on Constructionhistory, that being building materials, techniques and and the people who didthe work!From structures to frescos, we'll cover it all!Hosted by Darren McLean.
7. Roman Asbestos
05:22||Season 1, Ep. 7Did you know that the Romans - and others, such as the Greeks - used asbestos as a woven fibre?They valued its fireproof nature and used it accordingly. They may also be the first culture to have recorded using PPE! ☕ Buy Me a Coffee - https://ko-fi.com/buildlikearomanBuild Like a Roman is a podcast about how the Roman world was built.Focusing on materials, craft, and construction, each episodeexplores the practical realities of Roman building — from stone, brick, andmortar to the organisation of labour and technical skill behind survivingstructures.Short, focused episodes introduce core building materials beforediving deeper into how buildings were made, maintained, and understood in theRoman world.For students of archaeology, history, and art history — and foranyone interested in how ancient buildings actually came into being.North Africa and Western Asia are home to a multitude of Romanbuildings. Some still used on a daily basis, others in ruins, but that'stypically not the fault of the original builders. The fact that these stillexist at all after 2,000 years or more is a testament to skill and creativityof the original builders.There are some great Podcast which look at Roman politics,history, and architecture, however in this Podcast, we focus on Constructionhistory, that being building materials, techniques and and the people who didthe work!From structures to frescos, we'll cover it all!Hosted by Darren McLean.
6. Roman Metals: Iron, Bronze and Lead
16:01||Season 1, Ep. 6Why bury a Million nails?The Romans used a wide variety of metals, both ferrous and non-ferrous.Iron, lead, bronze, brass, tin and copper were all commonly used by the Romans.For structural connections, plumbing, door handles, decorative elements or any other practical use, in or for the home, the Romans had a solution!☕ Buy Me a Coffee - https://ko-fi.com/buildlikearomanThis Episodes Instagram image link: https://www.instagram.com/p/DU6MQ-JjVgl/Roman Metal Terms: Latin → EnglishFerrum → IronPlumbum → LeadStannum → TinAes → Copper alloy (bronze or brass)Cuprum → CopperCadmia → Zinc ore (used to make brass)Argentum → SilverAurum → GoldClavus → NailFibula → Fastener / clasp (sometimes a clamp)Fistula → Pipe (usually lead)Aes coronarium → Thin decorative bronze sheetAerugo → Verdigris (green corrosion on copper alloys)Note:The Romans did not separate “bronze” and “brass” the way we do today. Both were usually called aes — meaning copper alloy.For students of archaeology, history, and art history — and foranyone interested in how ancient buildings actually came into being.North Africa and Western Asia are home to a multitude of Romanbuildings. Some still used on a daily basis, others in ruins, but that'stypically not the fault of the original builders. The fact that these stillexist at all after 2,000 years or more is a testament to skill and creativityof the original builders.There are some great Podcast which look at Roman politics,history, and architecture, however in this Podcast, we focus on Constructionhistory, that being building materials, techniques and and the people who didthe work!From structures to frescos, we'll cover it all!Hosted by Darren McLean.
5. Roman Timber: Roofs, Doors and Forgotten Walls
21:19||Season 1, Ep. 5This episode is looks at the Romans use of timber, be it structural, joinery or temporary. Timber is somewhat of a forgotten material by most people who looking at Roman archaeology, mainly as there's so little of it left. This week we aim to give Roman timber, a little more of the limelight.☕ Buy Me a Coffee - https://ko-fi.com/buildlikearomanPhotos of this episode: https://www.instagram.com/p/DUq9pxzjeyO/Term = DefinitionMateria: General term for timber (as opposed to lignum, which usually referred to firewood).• Abies: Fir. The primary wood for long-span roofing due to its straight grain and high strength-to-weight ratio.• Quercus: Oak. Valued for its density and used for "wet-work" or heavy load-bearing sills.• Larix: Larch. Highly prized for its natural resistance to fire and rot; often used in maritime or bridge engineering.• Contignatio: A timber floor or ceiling assembly. This refers to the entire system of joists and decking.• Tignum: A general term for a structural beam or log.• Trabs: A large main beam, typically horizontal, used to support secondary joists.• Statumen: The secondary layer of a floor; cross-battens or "stiffeners" laid over the main beams.• Scandula: A wooden shingle. Used for roofing before the widespread adoption of terracotta tiles (tegulae).• Opus Craticium: A timber-frame construction method. It involves a wooden lattice (wattle) filled with mortar or clay (daub). Oak (Quercus): The "Iron" of the Roman forest. Used for ground-contact sills and heavy-load lintels. Cato advises cutting oak only when the sap is down (winter) to prevent rot. Fir (Abies): The backbone of Roman roofs. Sourced from the Apennines. Vitruvius (De Architectura, Book 2.9) praises Fir for its lightness and stiffness, essential for long-span trusses. Larch (Larix): The "Fireproof" wood. Vitruvius notes its resistance to fire and rot, making it the premier choice for bridge pilings and high-moisture For students of archaeology, history, and art history — and foranyone interested in how ancient buildings actually came into being.North Africa and Western Asia are home to a multitude of Romanbuildings. Some still used on a daily basis, others in ruins, but that'stypically not the fault of the original builders. The fact that these stillexist at all after 2,000 years or more is a testament to skill and creativityof the original builders.There are some great Podcast which look at Roman politics,history, and architecture, however in this Podcast, we focus on Constructionhistory, that being building materials, techniques and and the people who didthe work!From structures to frescos, we'll cover it all!Hosted by Darren McLean.
3. Introducing Roman Brick and Tile
22:47||Season 1, Ep. 3This week, the Build Like A Roman Podcast episode is about fired clay, for bricks and roofs.☕ Buy Me a Coffee - https://ko-fi.com/buildlikearomanPhotos of this episode: https://www.instagram.com/p/DUS--yyjTTR/The Episodes Translations:Opus vittatum mixtum (listatum) = Alternating brick and stone coursesOpus mixtum = Combination of stone and brick facingsOpus testaceum = Concrete faced with brick/tilesOpus vittatum / listatum = Banded tufa/brickOpus latericium / testaceum = Brick‑faced concreteOpus mixtum (reticulatum mixtum) = Mixed brick‑reticulatePedalis = One‑foot tile/brickSesquipedalis = 1½‑foot brick/tileBessalis = Two‑thirds brick/tileTegula = Flat pan tileImbrex = Cover tileLater / laterculus = Thin wall tileLateres Crudi = Unfired bricksLateres Cocti = fire bricksReading materials:Roman building: materials and techniques, Adam, JP (1994)Roman Building Techniques, Rook, T (2013)Roman Builders, Taylor, R (2003)Build Like a Roman is a podcast about how the Roman world was built.Focusing on materials, craft, and construction, each episodeexplores the practical realities of Roman building — from stone, brick, andmortar to the organisation of labour and technical skill behind survivingstructures.Short, focused episodes introduce core building materials beforediving deeper into how buildings were made, maintained, and understood in theRoman world.For students of archaeology, history, and art history — and foranyone interested in how ancient buildings actually came into being.North Africa and Western Asia are home to a multitude of Romanbuildings. Some still used on a daily basis, others in ruins, but that'stypically not the fault of the original builders. The fact that these stillexist at all after 2,000 years or more is a testament to skill and creativityof the original builders.There are some great Podcast which look at Roman politics,history, and architecture, however in this Podcast, we focus on Constructionhistory, that being building materials, techniques and and the people who didthe work!From structures to frescos, we'll cover it all!Hosted by Darren McLean.
2. Stone: Tuff, Travertine and Marble
12:45||Season 1, Ep. 2Rome began with houses of mud-brick. Then came stone.This week, the Build Like A Roman Podcast introductory episode is about Stone, in particular Tuff, Travertine and Marble. While not used uniformly across the Roman empire, they were ubiquitous in the City of Rome and the surrounding region.☕ Buy Me a Coffee - https://ko-fi.com/buildlikearomanPhotos of this episode: https://www.instagram.com/p/DUOEesoiHfq/Build Like a Roman is a podcast about how the Roman world was built.Focusing on materials, craft, and construction, each episodeexplores the practical realities of Roman building — from stone, brick, andmortar to the organisation of labour and technical skill behind survivingstructures.Short, focused episodes introduce core building materials beforediving deeper into how buildings were made, maintained, and understood in theRoman world.From structures to frescos, we'll cover it all!Hosted by Darren McLean.Term = DefinitionTuff = A volcanic rock (pyroclastic) formed from consolidated ash and debris. Easy to cut allowing for fast construction.Tufa = A sedimentary limestone formed by mineral precipitation from freshwater springs, much softer and less durable than volcanic tuff.Travertine = A hard, dense limestone with high compressive strength, formed in hot springs.Marble = A metamorphic rock (recrystallized limestone) that takes a high polish.Basalt = A hard, durable volcanic rock that was nearly indestructible but very difficult to cut.Limestone = A broad category of sedimentary rock with varying properties.Sandstone = A sedimentary rock whose strength varies based on its composition. Darker varieties are sometimes called "brownstone."Vernacular Building = The principle of constructing buildings using materials that are readily available locally, which often determined stone choice and led to regional traditions.Veneer / Revetment = Thin slabs of decorative stone (usually marble) used as a non-structural cladding over a cheaper core material to display wealth.Opus Quadratum = A construction technique using large, rectangular ashlar blocks laid in regular courses without mortar.Opus Africanum = A regional North African building technique which includes long vertical stone piers.Ashlar = Precisely cut and dressed stone blocks with regular faces and right-angled corners, used in techniques like opus quadratum.Lapilli = Latin for "little stones".Cramps = Metal fasteners used to secure stone blocks or veneer panels together.For students of archaeology, history, and art history — and foranyone interested in how ancient buildings actually came into being.North Africa and Western Asia are home to a multitude of Romanbuildings. Some still used on a daily basis, others in ruins, but that'stypically not the fault of the original builders. The fact that these stillexist at all after 2,000 years or more is a testament to skill and creativityof the original builders.There are some great Podcast which look at Roman politics,history, and architecture, however in this Podcast, we focus on Constructionhistory, that being building materials, techniques and and the people who didthe work!From structures to frescos, we'll cover it all!Hosted by Darren McLean.