Has anyone experience of fitting a padstone into a clay lump wall. We are changing a ceiling beam and the structural engineer has done the calcs and give me a padstone size for it to bear on. My only worry is the bedding of this padstone onto the clay lump. A bed of M4 mortar seems to be the popular choice. I envisage the clay lump sucking the water out of the mortar before it has properly set, maybe I am overly pessimistic.
- Thread starter Bogart
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george2019
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Compressive strength of M4 mortar is 4MPa @28 days, so a NHL5 mix could be substituted with approval of the SE - this should give a bit more flex for the padstone to clay lump wall interaction over the long term. I wouldn't be overly worried though as even if cement did crack, the padstone gives enough load spread to prevent any problems.
Wait for cool weather, pre-wet the wall to reduce suction and cover the padstone/mortar with plastic sheet and hessian to prevent rapid moisture loss, not much else you can do.
Wait for cool weather, pre-wet the wall to reduce suction and cover the padstone/mortar with plastic sheet and hessian to prevent rapid moisture loss, not much else you can do.
I forgot to mention is an internal wall in the kitchen, currently stripped out so no cooking heat nor any from the radiators as switched off. I like the idea of the slightly flexible bed for the padstone.
It has been suggested that instead of using a single padstone engineering bricks are used. On a normal wall I would not have a concern over this but I think on this clay lump I would prefer one big single padstone.
It has been suggested that instead of using a single padstone engineering bricks are used. On a normal wall I would not have a concern over this but I think on this clay lump I would prefer one big single padstone.