A faucet assembly includes a base having first and second ends, a sidewall extending between the ends, a mounting bore extending from the first end, a permeate water spout port extending from the second end, and a valve assembly bore extending from the sidewall and connecting the mounting bore and the permeate water spout port. A fastener is located within the mounting bore and extends out of the base from the mounting bore for securing the faucet assembly to a mounting surface, and a valve member is positioned within the valve assembly bore and movable between closed and opened positions. The valve member allows tool access from the permeate water spout port, through the valve member, and to the fastener in the mounting bore when the valve member is moved to a predetermined position. This arrangement allows top-mounting of the faucet assembly using a toggle bolt.