Uncovering a Big Problem

A retirement community in Northern Illinois contacted Trenchless Innovations to look at their deteriorated ducts in their cottage home units.  DuringRetirement the video inspection, our team discovered that the ducts under the slab floor were cardboard. The ducts were deforming due to moisture and standing water in the soil coming in contact with them.  In many areas, the deteriorated cardboard ducts were so collapsed that the camera could not pass through them. Although cardboard seems like an odd choice for underground air ducts, it was a popular choice among builders from the 1950s to the 1980s. This wasn’t the first time Trenchless Innovations had seen this type of duct.  

Air Duct Repair Begins

The first step our team took to repair the system was to thoroughly clean the ducts, including peeling the collapsing cardboard from the ducts. Once cleaned, our next step was to restore the structure back to the compromised ducts by applying a spin cast mortar to the inside of the old ducts. Here at Trenchless Innovations, we use a specialized mortar with fiberglass mixed in that is designed to be used in horizontal piping and that provides a solid structure to the ducts.

Lining Underground Air Ducts

With the mortar applied and the ducts structurally sound, our team then spray lined them with a rubberized duct lining material, covering and sealing the new concrete ducts. The liner also contained 3% zinc which acts as an antimicrobial in case of future moisture in the ducts.

A Breathe of Fresh Air..and a Sigh of Relief!

Trenchless Innovations performed all work in the cottage homes with very minimal disruption to residents. In fact, some residents remained in their homes during the duration of our work. The repairs were done with no destruction to the floors or walls and residents were left with nothing but clean and healthy air to breathe.