I wanted to share with you a little more about what came out of the interview last week with Heather Brown’s “Good Question” on WCCO, TV and what followed. Mainly, I want to back up the statement I made about loud noises or creaks in the home because I got a mild amount of pushback. I decided to show proof so that people actually understand the consequences of warm meeting cold in the attic.
Last week I mentioned that a builder’s explanation for the loud booming noise was, “no big deal” and “just a settling of the home”. My comment was, “the loud booming and cracking sounds could be a signal of issues that are actually quite detrimental to the performance of the home, lumber could be moving”.
The following photo shows where the roof truss has separated from the roof deck of this west metro complex.
This is an example of what can occur when warm air from the living space meets the cold air in the attic space starting the expansion and contraction cycle which can lead to compromising your building elements. Different types of lumber or materials have varying properties causing their movement behaviors to be diverse. Plywood is filled with glue which moves differently from a roof rafter which is made from a softer wood with no glue added. Similarly, the structural members typically are made of different materials than these joining members, such as structural beams, which do not match the movement of the other elements.
Most often these roof noises occur when exterior temperatures reach extreme lows. The loss of heat in the living space meets the cold structural members in the attic causing physical movement or “booms”. Because of expansion and contraction, and due to the varying material properties, there are times when lumber will move and will change the load bearing properties and capacity. Particularly during a winter with heavy snowfall.
We at CBS, can help you with your building’s performance to eliminate heat loss, ventilate your attic space correctly and prevent these occurrences