With the money, knowledge, and connections SGPC has, they should be hiring experts to preserve these buildings and solidify them for the coming centuries.
SGPC had to bring international scientists to make sure the Dukh Bhanjani Beri didn't DIE at Sri Darbar Sahib due to the Marble around it (which was put by Kar Seva Babas), the tree roots couldn't get enough nutrients. Why SGPC can't do the same with buildings baffles me.
There are also many other Historical trees in other gurdwaras that are either dead or dying, but no one cares as they aren't popular gurdwaras like Sri Darbar Sahib.