We bought a house built in 1940 that was literally ceiling to floor WOOD in the den. Knotty pine on the walls and pretty wood floors . It has a huge stone fireplace as well. It was the ONE room besides the kitchen that I knew had to be redone. All of the men in the family we balking at painting the knotty pine...scoldings, cussing , all kinds of noise went on. Eventually, I won. We used something simular to terminator 2 kilz... NO SANDING...Just the primer ( which dries incredibly fast ) . The trim went white ...the walls... a beautiful sage green. OMG when I can I will post the before and afters. Rave reviews and the men recanted their mumblings. It is SUCH an improvement. If you are thinking about it... GO FOR IT! You will not be disappointed!