Many people dread January’s subfreezing temperatures. But for those with a fireplace, like Ken Fulk, winter is something to look forward to. In fact, among the three homes that he shares with his husband, Kurt Wootton, and his office in downtown San Francisco, Mr. Fulk has not one fireplace, but five. He and Mr. Wootton “would not choose to live in a home without a fireplace,” he said. “Any home we have has at least one.” As an interior designer and event planner (he helped plan Sean Parker’s wedding), Mr. Fulk, 48, enjoys the accessories and the ritual surrounding building a fire almost as much as the fire itself. “It’s quirky and wonderful that something relatively simple and primitive has all of this great jewelry that comes with it,” he said.