Repairs to property

sir the study text says that repairs expenses are allowable expenses so long as they are wholly and exclusively related to property. But on the other hand, under the special rules mentioned for buy-to-let residential property there is a statement saying that 25%+75%*20% rule applies to all interest payments made to ‘acquire, improve or repair’ residential property. This apparently seems to suggest that if i buy a residential property and make some repairs to it by shelling my own savings then the entire repair expenditure is allowable, but if i take a loan for the same residential property then only 25%+75%*20% is allowable? is that right?