Non-hollow core doors provide better sound isolation and speech privacy than hollow core doors, which can allow sound to leak through. According to the WELL v2 standard, doors that connect two occupiable rooms and doors to mechanical equipment rooms should have a non-hollow core, minimum STC/Rw of 30 and seals at the head, jamb and base.
References: = WELL v2 Sound Feature S03, WELL AP Candidate Handbook
To reduce sound transmission between adjacent spaces, using non-hollow core doors for private offices and conference rooms is an effective strategy. These doors, being more solid than their hollow counterparts, inherently offer better sound insulation. This characteristic helps to minimize noise leakage into and out of these spaces, thereby enhancing acoustic privacy and reducing distractions. This measure, in conjunction with other sound isolation practices, contributes to a more conducive working environment by maintaining the confidentiality of discussions and improving overall acoustic comfort.