Unfilled mortar joints in masonry are a violation of law and a breach of contract. Why? Because most specifications and building codes require filled joints. Unfilled head, bed, and collar joints are common, even though they're forbidden. Water penetrates the unfilled joints, causes damage, and the owner sues the contractor. Those who think it's okay to leave joints unfilled because everyone does it should know that the courts don't agree. Even if it's a common trade practice, it's a violation of contract or law-and thus punishable. Proof that the work violates the building code is proof of negligence. Masons know how to fill mortar joints. All they need is some encouragement from management to do it.