What I'm wondering is how much you soaked the bricks when you were building? If they weren't dipped in water for a while, I think what might have happened is that the bricks absorbed too much water from the mortar before it had time to set. The poor adhesion between the mortar and the stone could be explained by this.
Does the mortar seem solid, or is it crumbly/sandy?
By the way, a very fine staircase that can never be replaced by pressure-treated wood!
Does the mortar seem solid, or is it crumbly/sandy?
By the way, a very fine staircase that can never be replaced by pressure-treated wood!
Thank you for your response, Evakatarina. Yes, the stones were quickly rinsed with a water hose before they were placed against the mortar on the staircase foundation. This happened in the mornings before the sun was up; after 10:00, the sun was on, and it was during a period with temperatures around 25 degrees. The mortar is intact and cohesive but, as you say, detaches from the stones, which suggests that they did not fully adhere.E Evakatarina said:
Regards, gz
Ok. You should at least shade from the sun and perhaps also keep it damp. Is it possible that there is soot left on the back of the stones?G GustafZ said:
Since the damages seem to be concentrated on the lower part of the staircase and I now also see that the corner has sunk, the next question is how the foundation and drainage were done?
Indeed. The stairs have been shaded with tarpaulins during the day and watered to keep them damp the next few days after casting.E Evakatarina said:
All the stones have been ground/brushed with a wire brush on the "casting surface" to ensure they are clean.
No settling has occurred (the foundation stands solidly). However, the stones have detached from the mortar and started to move downward.
// G
No, the stones are cast against the foundation on the back of the stones. The bottom stones are also attached on the back where there is a small ledge to rest on. However, that ledge only extends a few cm out to keep the stones in the correct position during casting.
Either I am misunderstanding or you have made a mistake when building the staircase. If the bricks are truly hanging in the air without solid support underneath, it will never hold. Mortar or cement is not a superglue for bricks.
No, of course they have support underneath holding them up (90% of all the bricks on the bottom row are untouched) the only ones that have loosened are the outermost in the southwestern part of the stairs, which is likely due to something other than insufficient support underneath.MultiMan said:
Very beautiful staircase, I have no tips but wish you success in your repair so it can continue to adorn your entrance 🤩
