Ask the Architect

We failed on insulation and fire stopping

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Q. We’ve had construction on our home going for what seems like forever. We got stopped by the pandemic in April (after starting right before, in March), and didn’t really get going again until July. A building inspector told us the insulation didn’t pass, and there was no “fire stopping.” The contractor said he followed the plans. We looked at the plans and the permit, and it doesn’t say anything about fire stopping. First, why didn’t the insulation pass, and second, what is fire stopping? We’re about to throw in the towel. Help!

A. You don’t need a towel to throw in or even clean up the mess; you just need to know that not all insulation is the same. Either the insulation was the wrong type or thickness, or it may have been installed incorrectly. In the past decade, the federal Department of Energy has issued more stringent guidelines on what thermal ratings must be installed for floors, walls and roofs. Your state, following the DOE, sets codes based on regional requirements to save energy.
If you look at the plans, there should be information about what R value was designed and approved. R stands for resistance, and is printed on each bale of fiberglass. If the insulation installed was a lower number or was jammed into a narrower cavity, that may be a reason to fail. Another common failure is using open-cell foam insulation when closed-cell, which has a higher resistance, and cost, was specified in the drawings. Another common error is when air gaps allow cold air to creep right through. I often see where fiberglass insulation is forced into the gaps around windows, and when fiberglass batting is compressed, it loses insulation value because the thermal resistance is in the air pockets, not the material.
Due to the formulas and calculations we professionals have to provide “online” for each job, this is taken seriously, so if the installer ignored the required insulation, the inspector could not pass non-compliant work. I respect your inspector for trying to protect your interests.
Fire stopping is an important safety factor in protecting occupants. All pipe and duct penetrations, by law, have to be sealed completely to prevent flames from drawing into cavities, seeking oxygen and rapidly consuming the building and trapping people inside. Anyone who builds must build legally, whether there’s a note on the plans or not. Although building officials like to see more and more informational notes to cover everyone in case of liability, site enforcement by inspectors is important.
Your builder has an equal responsibility to follow all the laws. As a professional witness, I remember hearing a judge once state, “Ignorance of the law is no excuse.” Trying to say that “it wasn’t in the plans,” doesn’t relieve a party to the construction of responsibility for building to the letter of the law. So check for gaps, insulation type and markings to verify you’ve got the right stuff. Stay warm!

© 2020 Monte Leeper. Readers are encouraged to send questions to yourhousedr@aol.com, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.