Breathable Building.
Breathable building materials, with the evidence.
Traditional UK brick building with period windows and architectural details

Breathable building materials,
with the evidence.

Plain-English research on lime mortar, lime render, breathable plaster and heritage construction. Every claim cited to gov.uk, Historic England, peer-reviewed research, and UK trade standards.

Read the first guide →

Why breathable materials?

Traditional UK buildings (pre-1919 solid walls, heritage listed properties, lime-built structures) need materials that let moisture move through the wall. Seal them with cement, gypsum, or modern paint, and you trap damp inside. That leads to decay, mould, and expensive remedial work.

Breathable building covers lime mortar, lime render, lime plaster, breathable insulation, and compatible finishes. This site gathers the research, translates the jargon, and cites the primary sources so you can make informed decisions for your own project.

Sources we cite

  • Historic England
  • Building Research Establishment (BRE)
  • Society for the Protection of Ancient Buildings (SPAB)
  • British Standards (BS EN)
  • gov.uk guidance
  • Peer-reviewed journals

Guides

Close-up of traditional lime mortar in heritage brickwork

Cornerstone · 8 min read · with breathability calculator

Lime mortar vs cement mortar: which for heritage walls?

Lime mortar lets walls breathe, absorbs movement, and protects soft bricks. Cement mortar is harder, waterproof, and can trap damp or crack historic masonry. When to use each, costs, application, and the evidence from Historic England, BRE, and 20 years of field monitoring.

More guides coming soon

  • Lime render: when to use it, application, costs
  • Breathable plaster vs gypsum: solid wall choices
  • Breathable paint and lime wash: what works
  • Breathable insulation for solid walls