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wrote:
mortar takes a month to get its full strength up. 5:1 is more than
strong enough. I take it youre using all new bricks, not salvo old
ones. If youre using old you need a different mortar altogether.

You are right I am using new engineering bricks but planning to use
older common bricks above them...thinking of using a 6:1 mix for them.

If youre using old bricks, there are several reasons not to use cement
mortar. You can of course, but lime has several advantages, especially
when used on houses with little in the way of foundations. I'd
definitely suggest using lime instead for the commons.

... A lot of 19th century houses wrere
built with sod all in the way of foundations.

You mean there are no foundations?

The only way to know is to dig down. In 1800s and earlier houses varied
greatly, some have good foundations, most have very little, some had
none at all. So who knows. 3 bricks deep is a very common Victorian era
foundation, and that may be all youve got.

So is there a damp problem or not? I'm not clear. The bricks in the
soil will of course be damp, but this wont normally transfer itself to
the living area. Think more explaantion is needed.

No there isn't a damp problem; I've simply assumed that laying new
bricks on top of slightly damp ones would required some waterproofer or
a new DPC. I've opted for waterproof mortar and a few rows of
engineering bricks.

Most 1800s houses had no dpc of any sort, and normally were fine. Damp
handling on old properties is somewhat more complex than with new
builds. There are a lot of old properties that have become damp as a
result of unsuitable maintenance, but few that are damp due to original
design.

NT