Hello,
Housing units with no windows:
I do not see how the design and construction of housing units without any window and access to daylight and fresh air could be truly legal. There is something quite amiss in this matter. And, the architect's duty is to protect "public health, safety, and morals..." and witnessing something such as this brings some obligations I would think or at least some queries as to how is this possible? There would be serious life safety risks if the subject building were to have a fire and the fire exit routes were blocked and the inhabitants of these suspect dwelling units were not able to make an escape.
Coatings on slate roofing:
Slate roofing shingles come in various qualities and life spans - depends on the quarry and the natural stone and how it was formed. All slates are not equal. One needs to study the specific slate quarry source and their long-term reputation for their behavior in the climate zone and application being considered.
But, I do not think the application of a foreign coating for snow and ice control to a slate shingle should be explored when there are very traditional ways of dealing with snow and ice accumulations on a sloping roof - those little and typically metal devices called snow birds or whatever. One, of course, will want to do whatever further measures below the slate course at the lower levers of the slope to deal with the risks of snow/ice melt - meaning appropriate insulation, vapor barriers, and backup membranes to capture any melt ro driven water that migrates through the individual slates themselves. In New England, the lower sections of the sloped roofs often have a metal roof covering that is exposed at these lower levels to deal with the winter snow and subsequent ice dam risks.
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George Siekkinen AIA
Center for Historic Buildings
Winchester VA
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