Traditional

Traditional Plasters

Sympathetic with older walls

Traditional Plasters using lime are centuries old and still of use today in older properties and wrongly regarded as being outdated by the production of portland cement and gypsum plasters. Lime plasters are commonly labelled ‘breathable’. However, Modern Plasters and Renders can trap moisture behind the wall if applied to traditional lime walls. Modern Plasters can also break down the Lime cycle by not allowing Carbon Dioxide to reach the lime mortar. This can cause pointing, render and plaster to fail. Types of Lime Air Lime or Non-Hydraulic is a lime plaster that takes the longest to set and cure and is considererd the most appropriate for older buildings. Hot Lime is very much a traditional product of a method not commonly used today using Quicklime. Its likely your home built a century ago used this method. Natural Hydraulic Lime (not to be confused with Hydrated Lime) comes in three strengths for interior and exterior walls. NHL 2 being the weakest set, NHL3.5 and NHL5 being the strongest set. It sets without exposure to air, therefore provides a faster set than Air Lime. Hydrated Lime is often added to Portland Cement to increase workability and make the cement more pliable. If you’re home was built before World War II it likely was originally built using Lime and therefore care and consideration should be taken to choose the right material in the long term. Even after this date, houses were still being built using lime materials, up until around the 1980s.

Other materials to look out for

Modern paints with silicone plastics can still bubble and crack if moisture becomes trapped between the layer of paint and a traditional plastererd or rendered wall. Even if the manufacturer claim the paint is breathable damage can still be caused if enough water is not released which results in the paint being force off the surface by moisture release.  Heritage plasterers recommend limewashes and silicate mineral paints or linseed paints to have maximum breathability and allow moisture to escape. Claypaints are recommended for interior decorating over lime walls. Many original walls have lining paper/wall paper and this does not stop the walls from breathing and protects the plaster.  This book contains plenty of information to help you make the right decisions in your period property.

Lath ceilings and cracks

Old lime and plaster ceilings attached to lath are notorious for deep cracks. This is fairly common if the original plaster is nearly a century old. It’s actually a testament to traditional plaster if the ceiling can last a century with only a few cracks, however its usually the plaster loosing its grip to the laths that causes cracks. Not to worry these cracks can often be repaired and restored and will help in the preservation of your home.

The solution

The solution is to remove modern plaster that is causing the failure of moisture to move freely, and to do this would be to use the correct lime mortar plaster. The same is true of exterior render/stucco.
More Info More Info
© This site was packaged and coded by Xara, designed using Xara Web Designer by Alexander Wilson.
Lime Finish on Chimney Breast
Application of Lime Plaster
Sand and NHL3.5 Mix in Bucket
lime frieze restoration
Traditional Crack Repair
Decorator & Plasterer

Traditional

Plasters

Sympathetic with

older walls

Traditional Plasters using lime are centuries old and still of use today in older properties and wrongly regarded as being outdated by the production of portland cement and gypsum plasters. Lime plasters are commonly labelled ‘breathable’. However, Modern Plasters and Renders can trap moisture behind the wall if applied to traditional lime walls. Modern Plasters can also break down the Lime cycle by not allowing Carbon Dioxide to reach the lime mortar. This can cause pointing, render and plaster to fail. Types of Lime Air Lime or Non-Hydraulic is a lime plaster that takes the longest to set and cure and is considererd the most appropriate for older buildings. Hot Lime is very much a traditional product of a method not commonly used today using Quicklime. Its likely your home built a century ago used this method. Natural Hydraulic Lime (not to be confused with Hydrated Lime) comes in three strengths for interior and exterior walls. NHL 2 being the weakest set, NHL3.5 and NHL5 being the strongest set. It sets without exposure to air, therefore provides a faster set than Air Lime. Hydrated Lime is often added to Portland Cement to increase workability and make the cement more pliable. If you’re home was built before World War II it likely was originally built using Lime and therefore care and consideration should be taken to choose the right material in the long term. Even after this date, houses were still being built using lime materials, up until around the 1980s.

Other materials to

look out for

Modern paints with silicone plastics can still bubble and crack if moisture becomes trapped between the layer of paint and a traditional plastererd or rendered wall. Even if the manufacturer claim the paint is breathable damage can still be caused if enough water is not released which results in the paint being force off the surface by moisture release.  Heritage plasterers recommend limewashes and silicate mineral paints or linseed paints to have maximum breathability and allow moisture to escape. Claypaints are recommended for interior decorating over lime walls. Many original walls have lining paper/wall paper and this does not stop the walls from breathing and protects the plaster.  This book contains plenty of information to help you make the right decisions in your period property.

Lath ceilings and

cracks

Old lime and plaster ceilings attached to lath are notorious for deep cracks. This is fairly common if the original plaster is nearly a century old. It’s actually a testament to traditional plaster if the ceiling can last a century with only a few cracks, however its usually the plaster loosing its grip to the laths that causes cracks. Not to worry these cracks can often be repaired and restored and will help in the preservation of your home.

The solution

The solution is to remove modern plaster that is causing the failure of moisture to move freely, and to do this would be to use the correct lime mortar plaster. The same is true of exterior render/stucco.
More Info More Info
© This site was packaged and coded by Xara, designed using Xara Web Designer by Alexander Wilson.