TL;DR:
Anyone have experience insulating the interior of a mid-Georgian brick home with a Lime/Cork render in a cold climate?
(Example products listed below)

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Hi Folks,

I live in a Clay Brick/ Lime Mortar home with a stone foundation built in 1796 (Middleton, New Brunswick, Canada). The walls are double wythe solid brick as far as we can tell.

I suppose our climate zone would be 7a, unless there’s a colder option than that! The area is wet & humid in spring& fall; cold and snowy in the winters. All in all, a challenging climate for this kind of home as far as heating. 

We heat with two woodstoves and would like to explore options for improving heat retention, but are limited in options as we do not want to cover the exterior brick with insulation, and have determined that interior wall insulation in any contemporary fashion will be detrimental to the health of the masonry.

There has also been some mis-treatment of the brick and stone foundation over the years, some parts having been pointed or parged with concrete, so any intervention should also have the goal of helping rather than hindering the drying of the masonry.

We have decided that the best solution will likely be to strip back the stud/drywall walls that have been built in from the original brick&plaster, take back the original plaster, and re-plaster with a lime-based rendering product that includes an aggregate such as cork. 

I have yet to encounter anyone in our area or online who has experience using these products in this fashion (eg. Secil Eco Cork or Diathonite Evolution).

I am confident that these are the right products in terms of masonry conservation, but would love to hear testimonials regarding the efficacy of these products for insulating in cold climates.

Thanks!