Building materials, from straw to glass are combined to bring to life anything from a lowly cottage to the cathedrals reaching for the skies up above.

As we’ve mentioned on our previous article on medieval buildings types, different types of buildings had different requirements (longevity, defensive capabilities) as well as cost (in materials and/or time). In addition to that there not many periods of human history that there is such a gap between the rich and the poor, and this difference is clearly demonstrated in the type of buildings that people inhabit or use.

In this article we will discuss a bit further the differences between the materials used and the reasons that were used. One of the reasons that we are exploring this is in order to prepare for the upcoming article on rules for building construction in terms of sourcing materials and the time-cost of building anything from a peasant’s house to a Cathedral or a mighty castle.

Base Materials

Base materials are the materials used for the bulk of the project. Most of the buildings used several materials for their construction but the finalized structure was defined by the material mostly used.

Straw

Straw might seem like a very lightweight material and we hardly come across it when it comes to archeological digs of medieval settlements. The truth is that Straw, by itself or as a major component was used across most houses during the middle ages.

Straw buildings like houses and barns were constructed by packing cuboid (rectangular) straw bales and stacking them on top of each other. In most occasions this structure would have been supported by a lightweight wooden frame. The roofs of these houses were also built by using straw and other dry vegetation, these roofs were used across many building types and are commonly known as Thatched roofs.

The reason we don’t find these houses in archeological digs is that due to the fact that Straw is a biodegradable material, building constructed with it have quite a short lifespan once they are abandoned.

Straw bales provided excellent insulation and they were very easy to come by after reaping at the end of summer and thus made an excellent choice for the serfs of the land. Sadly, they were also quite flammable, which contributed to their short lifespans.

Straw was also a very important component for the creation of wattle and daub

Wattle and Daub

Wattle and daub is a composite building material used for making walls, in which a woven lattice of wooden strips called wattle is daubed with a sticky material usually made of some combination of wet soil, clay, sand, animal dung and straw.

Wattle and daub may not be a raw material but its modular nature and comparatively easy construction made it an excellent construction material. There is evidence that wattle and daub might have been used since the neolithic era and the fact that in medieval times we still find housed built out of it, is a testament to its efficiency as a building material. It is more sturdy than straw and provides better insulation from the elements. As with straw houses wattle and daub houses also made use of a timber frame and used Thatched roofs.

Cob

Cob, like wattle and daub is also a compound material Traditionally, English cob was made by mixing the clay-based subsoil with sand, straw and water using oxen to trample it. The earthen mixture was then ladled onto a stone foundation in courses and trodden onto the wall by workers in a process known as cobbing. The construction would progress according to the time required for the prior course to dry. After drying, the walls would be trimmed and the next course built, with lintels for later openings such as doors and windows being placed as the wall takes shape.

As we’ve mentioned Cob buildings make use of stone foundation something that is was more rare in wattle and daub and straw structures. The main reason for it being that cob, as a very heavy in clay compound needs to have a better footing in order to support the superstructure of the building.

The walls of a cob house were generally about 24 inches thick, and windows were correspondingly deep-set, giving the homes a characteristic internal appearance. The thick walls provided excellent thermal mass which was easy to keep warm in winter and cool in summer.

The material has a long life-span which, where cob was available made a great way to construct permanent structures.

Buildings made of Cob did not make use of timber frames but timber was mostly used in order to shape doorways and windows or internal passages and room separators.

Due to the plasticity of the material cob-made houses are easily distinguishable by their curvy walls, an architectural style that was used a lot due to its uniqueness.

Finally cob houses were and, still are extremely resilient to fire which made them ideal candidates for a long-standing structure. Their roofs were in most cases thatched and in some occasions made of timber or even clay.

Logs & Lumber

Lumber was a very important part of most of the buildings during the middle ages. Essentially most of the framing of a house as well as the roof structure was made by wood. In England, Oak was used widely due to its strong resistance to humid weather. Although an important element of many buildings, solely wooden houses were not so commonly used. Lumber was though used in military structures before the introduction of the Norman stone defences. Actually many of the invaders of England brought wooden defensive structures ready to assembly (Like IKEA flat packed but some hundred years ago).

Although not in heavy use in England many of the Scandinavian countries used Logged cabins and structures like Halls since the Bronze Age (3500 BC). Also the Roman architect Vitruvius Pollio in his architectural treatise De Architectura. He noted that in Pontus (modern-day northeastern Turkey) dwellings were constructed by laying logs horizontally overtop of each other and filling in the gaps with “chips and mud”

Lumber was also used for the construction of important infrastructure like bridges

Clay & Brick

Although clay is used as both a construction and a manufacturing material, clays bricks and bricklaying became common practice in England very late during the medieval era.

Clay was an important component of daub as well as cob and it is widely used for pottery, but the technique for creating fire bricks that flourished in the Italian peninsula states since roman times, only came to central Europe during the 12th century and it would take several hundred years until it’s in England.

Slate

also referred to as schist or shale)

Slate was commonly used as a roofing material for rich houses due to its low water absorption properties.fixing is typically with double nails onto timber battens (England and Wales) or nailed directly onto timber sarking boards (Scotland and Northern Ireland). Nails were traditionally of copper. Both these methods, if used properly, provide a long-lasting weathertight roof with a lifespan of around 80–100 years.

Lime Mortar

Lime mortar or plaster was made by extracting stone from a limestone quarry (lime works) which was then processed into a lime kiln in order to be rendered into a malleable form (quick lime). This allowed Lime to be used for building, rendering, plastering and lime washing building. Lime power was also used as mortar in between stone slabs which provided very good insulation for the building.

In locations that Lime stone could not be found, oyster shells were used in kilns in order to produce a very similar material (both are calcium carbonate)

Lime wash was used as an external coat to many of the wattle and daub houses. This plaster would take the colour of the earth that is was mixed with which resulted in many cases in vibrant reddish, yellow or white colours plasters. An example of this washes can be found at the keep of Stirling Castle (white yellow plastered masonry) or in Tudor era Town houses (white plaster over wattle and daub within a timber frame)

Stone

Stone was used during the medieval times for a variety of purposes. Due to it’s sturdy nature, stone was an excellent building material for structures that were meant to inspire awe and last in time, in some instances, their capability of take a significant pounding was also quite important.

Bridges, Cathedrals, Castles and Manors all used masonry as their main structural component. Of course all of those buildings also made extensive use of lumber but, in most of them, even the frame was made of stone.

Due to its nature, stone required a very well-organized logistics system that started with mining in a quarry to transportation to the stone cutters and then the careful laying of it. It was this unique nature of stone that promoted the creation of stone mason guilds, Guilds of craftsmen that kept the knowledge of their art a double locked secret.

Stone is able to withstand any sort of climate and provided with perfect insulation against the elements as well as enemy bombardment. In addition to that stone buildings were able to build much higher and to support much heavier superstructures. The rigidity of the material also made true modular design possible that, in many cases needed no “filling” material since the sheer weight of the material was enough to ensure its stability.

Marble / Granite

With the exception of Limestone (Purbeck marble) that was used for some Cathedrals, marble and granite were not commonly used in the middle ages England. In later times (Renaissance) Marble is used to construct mostly civic buildings and in some cases religious.

At the same Marble as with clay bricks is commonly used in the Italian States.

Secondary materials

Iron, Copper & Lead

All three of these metals are used one way or another in medieval architecture. From the manufacturing of nails used through almost every building type to copper and lead being used for pipes and for the construction of cathedrals, (drainage, domes sheathing etc) which required materials capable to stand the test of time.

Iron rods and are also used for added structural integrity in many military and religious buildings.

Flint

In architecture, flushwork is the decorative combination on the same flat plane of flint and ashlar stone. If the stone projects from a flat flint wall then the term is proudwork, as the stone stands “proud” rather than being “flush” with the wall.

Flint was mostly used for decorative purposes where it was available but in some cases whole buildings were built using flint.

Soil and Turf

In some northern regions the roofs in order to keep the humidity and water out would have been build by applying a layer of soil under a layer of turf on the roof of the house. Houses and other buildings made that way would almost blend with the rest of the scenery making them very hard to notice from distance.

A popular culture example of this kind of houses were the hobbit holes of the shire

Glass

Glass, in most instances as stained glass was used commonly for the decoration of religious, civic and some military building. Stained glass allowed to sufficiently light stone buildings but also to decorate them in a way that will inspire awe to all that visit buildings that made use of it.

In conclusion

Although most of the buildings constructed during the middle ages were made of malleable materials like, straw, wattle and daub, cob and sometimes wood, Stone buildings were the only buildings that could survive nowadays. The fact that a building was built in stone showed the wealthiness of its owner. Manors, Churches, Cathedrals and Castles served as places of worship or for the defence of the surrounding area, but also as symbols of power and wealth which required in order sustain the Feudal state’s status quo.

References

Clarke, Snell; Tim, Callahan (2009). Building Green: A Complete How-to Guide to Alternative Building Methods : Earth Plaster, Straw Bale, Cordwood, Cob, Living Roofs. Sterling Publishing Company, Inc. pp. 276–. ISBN 978-1-60059-534-9 .

Pollio, Vitruvius (1914). Ten Books on Architecture. Harvard University Press. p. 39.

Lime plaster convervation http://conservation.historic-scotland.gov.uk/cement Retrieved 18 February 2015

Building Scotland – Lime (vimeo video) https://vimeo.com/37513460 Retrieved 20 February 2015