Hello,

I need to install "Crack Monitors", which consist of a plexiglass material, to the outside of a brick wall. It is an Historic site and I do not want to use the supplied epoxy for fear that it will deface the brick surface.

Does anyone have any other ideas as to what I can use to temporally (2 months) adhere these plexiglass (light weight) monitors to the brick surface?

Thank you!

Almost any adhesive or thinset will leave a residue on the brick and you can't go with one that can be washed off with water. I think tile grout, pre-mixed, would work well for 2 months. A wire brush and a sand blast with corn husk fractions would take the residue off.