New white papers on replacing material "in kind"
We aim to prevent as much loss of our properties' historic construction material as possible through proactive maintenance and conservative repairs and treatments. Nevertheless, some elements, like roofing or siding shingles, are sacrificial layers that need to be replaced as part of a maintenance cycle. Other elements might be subject to decay through exposure to weather or the natural aging process.
When we need to replace an element, the preferred practice is to use the same material type or species, dimension, texture, detailing, and compatibility - commonly shortened to the phrase “replace in kind.” In some situations, however, exact replacement in kind is impractical due to reasons of material durability or the location of the repair.