When people refer to lime mortar they're generally referring to mortar made with hydraulic lime or fat lime putty, sand and no cement. However, for most modern bricklayers and builders, the only exposure they've had to lime products is hydrated lime.

2. When people refer to lime
mortar they're generally referring
to mortar made with hydraulic
lime or fat lime putty, sand and no
cement. However, for most modern
bricklayers and builders, the only
exposure they've had to lime
products is hydrated lime.

5. Hydrated Lime is readily available at the local
builder's merchant and can be used to increase
the workability of cement mortar. It is used more
widely in schools and training centres where it is
mixed with sand (no cement) to make a mortar
that doesn't set, ideal for teaching brickwork.

8. Naturally, many people new to lime mortar
assume that hydrated lime is the key
ingredient, they know by experience that they'll
need cement to make it set. Unfortunately this
couldn't be further from the truth and is pretty
much contrary to the use of lime mortars
altogether.

11. True lime mortars contain
hydraulic lime or fat lime putty
(non-hydraulic lime). These two
types of lime do indeed set with
no need of cement, albeit more
slowly than cement. The real goal
with lime mortar is to eliminate
the use of cement which is
unnecessarily strong, rigid and is
not breathable

14. Natural lime mortars are flexible,
allowing for movement in the
building and thus preventing
cracks in the masonry.
Furthermore, they are breathable
(vapour permeable), drawing the
vapour present in the masonry
back out into the air. This
breathability naturally draws and
damp and also helps to prevent