Normally the membrane would be the responsibility of the Owners Corp but if it has been damaged by the installation of boards, then the person who installed tem and damaged the membrane is responsible.
And before the frenzy of finger-pointing starts, the chain of responsibility has not alteres. The OC needs to attend to the fixing of the common property memberane, than they need to send the bill for repairs to the owner who damaged it.
What should not happen is the OC ordering the owner to fix it and then not being able to get it done because they refuse saying it's not their fault.