Lime plaster or cement:which one actually lasts
Lime is slower, softer and less predictable than cement plaster. We use it anyway, and this is the argument for it.
Cement render is harder than the masonry behind it. When the wall moves — and every wall moves — the render cannot. It cracks in a straight line and traps water behind itself.
Lime is weaker than the wall. It gives, it carries moisture out rather than holding it in, and it closes fine cracks on its own as it continues to carbonate. A lime wall gets better for about the first decade.
It costs more in labour and less in material. It cannot be rushed: each coat must be thinner than the one below it and must be allowed to take up before the next. On a Deccan summer site that means damping down the wall morning and evening for days.
The finish is the reason clients ask for it and the reason we keep offering it. Light does not sit flat on lime. It moves across the surface through the day, and the wall looks different in the morning than it does at five o'clock.
Lime plaster
- Lets damp move out through the wall.
- Closes its own hairline cracks over time.
- Ages slowly and can be patched.
Hard cement render
- Traps damp behind it.
- Cracks in long straight lines.
- The damp then shows up inside the room.
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Written by the studio. If you would like to discuss any of this against a specific site, get in touch.