When was lime mortar replaced by cement mortar?

[Jane Smith]

Hello, everyone. I'm trying to find out a rough date for when houses started to be built with cement mortar rather than lime mortar. As usual I expect I'm oversimplifying the issue here, but some sort of guideline would be very much appreciated. Thank you!

 

[Gervase]

There's no simple answer, I'm afraid. As a rough rule of thumb, pre-1914 is likely to belime, post is probably cement, but there again...
What we know as Portlant cement has been around since the early 19th century, and hydraulic lime mortars were very popular too, so you might find a hard, seemingly impervious mortar on a pre-Victorian house that is either cementitious or hydraulic.
The vast bulk of London's mid-to-late 19th century speculative housing boom was constructed with a mortar that would today equate to an NHL1, while important buildings were constructed with hydraulic lime made from blue lias which is very much like cement in its characteristics. "Concrete" in the form of a hydraulic lime and rough aggregate concrete, was also in use in the 19th century, and could be very hard indeed (as I know from experience, having once laboured on an archeological dig trying to excavate below some Victorian foundations on the north bank of the Thames near the Mermaid Theatre).
Of course, there are some very old buildings indeed which were built using cement and concrete - the Pantheon and the Coliseum on Rome being but two that have survived for a couple of millennia.
And some places carried on using lime mortar up to living memory. Before Christmas I was talking to and old chap whose job it was to slake batches of lump-lime and then chop the resulting putting into mounds of sand to make batches of mortar, which were then covered by tarpaulins. these mounds would provide all the mortar for a single building, and it took a lot of physical effort to 'knock up' enough each day for the masons or brickies. This would have been in the later 1930s.

 

[andrew gayton]

Of course, there are some very old buildings indeed which were built using cement and concrete

which was infact lime based mixes with pozzolanic material..... brick and stone, volcanic ash.............

 

[Jane Smith]

Thank you! That's just what I needed, and a little bit more. You've been a great help.