Do you know if there there issues with their weight? I thought that any upgrades or modifications to buildings on the historic register had to get all kinds of approvals for appropriatemess, engineering, building integrity and architectural studies etc.
Great question!
Different states and localities have specific codes and regulations that must be followed when determining whether the roof will support the weight of the panels.
The weight of the panels ordered is largely dependent upon how many solar "arrays" are needed to produce the amount of electricity desired.
The weight of a volume of snow as well as the force of wind during a storm or hurricane must also be factored into any installation on a roof in order to forestall roof collapse or the roof "raising up". Likewise the age of the building is another factor. The panels in most cases have to be bolted to existing "rafter" beams and timbers which cannot be weak or inwardly rotting and are in need of replacement.
It would be interesting to see the application for approval for the installation as well as any back-and-forth communications between the local code department and the White House, plus the specifications for the layout and weight of the solar arrays and for the installation.
The age of the White House is 221 years. Of course, numerous reinforcements, repairs, architectural changes and the like have been done rather consistently during the decades.
Leni