“Endowment” refers to funds given by a donor who tells the charity to hold the fund forever and use only the income (or a part of the income) for current charitable expenses.  Therefore, without getting approval of the donor, the Attorney General or a court, you can’t use the principal to fix the roof.  If the donor didn’t specify the purposes for which the income must be used, you can use it for any charitable purpose of the organization and fixing the roof would qualify.

You don’t say how much you have in total endowment or how any additional amount may be invested.  You ought to have an investment policy for allocating the investment of the total endowment, particularly between equities and fixed income investments.  Since you have an unlimited time horizon and because stocks have historically outperformed bonds, a large portion of your endowment, probably somewhere between 70-80%, is generally invested in stocks.  If it has been in a CD for 23 years, you have “lost” a lot of money.  It might make sense to put some of it in a low-cost stock index fund.

Under the Uniform Prudent Management of Institutional Funds Act adopted in 49 states other than Pennsylvania (See Ready Reference Page: “New UPMIFA Sets Rules for Management of Charitable Funds”) and under the spending rules of Pennsylvania, you can use some of the anticipated appreciation for current spending.  You can spend up to 7% of the value of the endowment each year (although about 5% may be more prudent), but if it is earning only 1% you would be cutting into the principal value.  That would not be prudent over time.

The endowment must be retained in perpetuity, and if the organization goes out of business, it must be transferred for other charitable purposes.  Normally the board of the disappearing organization can direct the transfer, but in the absence of its action, a court will decide where it should go.