One of the challenges we face when doing High Energy retrofits of NY masonry brownstones, by the Passive House standard for example, is how to install insulation that will both be effective and maintain the historical integrity of the building. Most existing insulation materials have limited usefulness when installed on the interior of the envelope, due to condensation risk and potential freeze-thaw issues.
Enter Hempcrete. Hemp-lime insulation, due to its vapor permeability and the material’s virtual thermal mass, has proven to be an effective way to retrofit historic masonry buildings for improved insulation, and is now being used widely throughout Europe.
This opens up exciting possibilities for effective and affordable ecological renovations of New York’s many historical brick buildings.
Although well established in Europe, this technology is new to the USA. We have studied it a lot and Eco Brooklyn is eager to be a NY hempcrete installer. Since hempcrete can be either insulation or actually act as an insulating semi-structural material (like SIPs but without the plastic), we think that it offers a lot of options for high efficiency NY Brownstone renovations.