Cob Work

Cob, an ancient composite of mud and straw, comprises the original infrastructure of countless historic buildings across Devon and beyond. Our extensive expertise with this traditional medium makes us ideally suited to preserve cob's unique vernacular legacy.

Cob has two main forms - compressed blocks dried for strength, and pliable on-site mixtures layered into lifts. We utilise cob blocks for versatile, structurally sound applications like chimneys, garden walls, and home exteriors, both new builds and repairs. Natural cob is added in lifts, gradually built up and cured to maintain integrity. Lime mortar bonds the blocks, while lime plaster protects the outer surface.

During repairs, we integrate new and old cob using stainless steel "helibars" to bind layers together. Supplementary natural materials like clay tiles and bricks patch deteriorated sections. Most regulators insist on "like-for-like" cob repairs rather than disruptive modern treatments like concrete blocks or cement renders. Such inappropriate materials seal cob walls, preventing natural transpiration of moisture.

Much damage to antique cob derives from this moisture buildup. Once we repair the cob and replace cement with breathable lime mortars and renders, the cob can re-stabilise to its ideal humidity. The flexibility and vapor permeability of lime preserves the longevity of this ancestral medium.

Veritably a local signature, Devon's cob architecture is a living heritage. Our specialised expertise not only repairs cob walls but retains their traditional essence and connection to the past. By maintaining the health of walls that have stood for centuries, we ensure this ecological, economical, and iconic building tradition endures long into the future. Our respect for traditional ways keeps cob's legacy alive.