Can you use lime mortar indoors?

Traditional lime plaster

Air-lime plasters and renders have been used for centuries indoors and outdoors. The atmosphere created with air-lime plaster is light and cool with an unmistakably refreshing ambience. The natural and breathable surface enables a healthy indoor climate.

Why lime mortar is not used?

Most of the bricks today are harder bricks which may make it safer to use hydrated lime/cement mortar mixes today but older bricks found in historic buildings were often poorly kilned in the first place and barely have glazing at all and so soft that its almost like slightly glazed sandstone.

When should you use lime mortar?

The use of a lime mortar for pointing in general masonry allows you to use a material that is both porous and softer compared with mortars that feature cement. This allows the moisture to evaporate from the joints more effectively which reduces the level of moisture in the fabric of the building.

What are the disadvantages of lime mortar?


  • the rapid setting time limits the time available to the user in which to work with the gauged mortar.
  • some cements contain appreciable amounts of soluble salts, in particular potassium sulphate, which may become a source of salt damage to stonework.

What is the difference between lime mortar and lime plaster?

Whilst lime mortar is predominantly a building material, used to bind together masonry, lime plasters and renders need to be spreadable and may therefore contain more water and a finer aggregate.

How do you apply lime plaster interior?

Quote from the video:
Quote from Youtube video: We're going to do this in two very thin coats. About one to one and a half million.

How long does lime mortar last?

Lime should be stored as long as possible before use: two months is the absolute minimum; after six months the lime will be much easier to use; and after one year it will be better still. Well stored, it will last indefinitely. There are many outlets for lime putty, some of whom hold stocks of older putty.

Is lime stronger than cement?

Its binding strength is less compared to cement. It has strong binding properties than lime. Lime hardens slowly when mixed in producing mortar. The cement hardens quickly when mixed in a mortar.

Why does lime mortar crumble?

Crumbling or failing mortar can be caused by a number of reasons: Failing mortar can usually be attributed to a lack of carbonation of the lime within the mortar meaning that the mortar will have little if any, strength.

Does lime harden like concrete?

Physical Properties

Lime hardens much more slowly than cement-containing mortars, making it much more workable. Lime is also less brittle and less prone to cracking, and any cracked areas can absorb carbon dioxide and mend over time.

What is the correct mix for lime mortar?

Traditional lime mortar is a combination of lime putty and aggregate (usually sand). A typical modern lime mortar mix would be 1 part lime putty to 3 parts washed, well graded, sharp sand. Other materials have been used as aggregate instead of sand.

How deep should lime pointing be?

The joints need to be raked out to a suitable depth, with the general rule being that it should be at least one and a half times the width of the joint, in the case of wide joints common sense should prevail.

Can you put lime plaster on plasterboard?

Solo Lime Plaster

Solo can be applied directly onto plasterboard, wood fibre board or a lime base coat of Duro or Ultra.

Should I use lime or gypsum plaster?

Compared to gypsum plaster lime plaster is far more breathable, allowing moisture to escape and evaporate, as well as actually drawing moisture out of the house.

Is lime plaster better than gypsum?

Unlike gypsum or clay plaster, lime plaster is sufficiently durable and resistant to the elements to be used for exterior plastering. Compared to cement plaster, plaster made from hydrated lime is less brittle and less prone to cracking, requiring no expansion joints.

When did lime plaster stop being used?


Lime plaster is the traditional finish for houses pre-1919, but may have been used up until the 1950s when plasterboard and gypsum took over.

Is lime mortar expensive?

+ Lime mortar is generally more expensive than cement based mortar? Yes, it is more expensive due to production cost of lime vs cement, basically down to volume of production. As more lime is produced, cost will reduce.

Is there an alternative to lime plaster?

Cement render is usually a cheaper alternative to Lime or Polymer renders. The rigidity of cement render usually limits it’s application to older buildings, where flexibility of finish is usually required to overcome structural movement.

Does lime mortar stop damp?

Lime mortar tends to let walls ‘breathe’: lime-pointed brickwork can take in, but also release moisture from the atmosphere. If a house was made with bricks that aren’t particularly porous or breathable, then lime mortar offers an important way for moisture to make its way out of the house.

What is the difference between lime mortar and Portland cement?

Portland cement is about 30% clay-based, while lime is usually about 5% clay. However, there are three basic strengths of lime mortar, depending on the amount of clay present. The closer the clay percentage gets to 30%, the closer it is to a Portland cement, since the strength will be the same.