When a renovation is nearing completion, there are two steps that need to be taken to ensure the majority of the chemicals are no longer in the indoor space: a flush out and product loading.

Flush Out

A building flush out is an important step in finalizing a project. A flush out is a process in which the VOCs or chemicals released from the products used during the renovation are flushed out of the building by fresh air, allowing for improved indoor air quality. The flush out should take place after the renovation is complete but before occupancy. The process is accomplished by using the building’s mechanical system to circulate fresh outdoor air throughout the building. Using the building’s mechanical system strips the humidity out of the air while still allowing the fresh outdoor air to be brought into the indoor environment. Ideally, a flush out would take place for two weeks, but any amount of time is better than not conducting a flush out at all.

Avoiding Sink Effect

Product loading is when products (such as paint, carpet and furnishings) are brought into or loaded into the renovated area. Proper sequencing of these materials and products is essential in minimizing the amount of VOCs in the new space. Oftentimes, this process is outlined in an indoor air quality management plan, but the general rule of thumb is wet products before dry. By applying this rule, the sink effect can be avoided. The sink effect is when chemicals from wet products are absorbed by porous materials (carpet, furniture, ceiling tiles, etc.) and then are re-emitted into the indoor air for a longer period of time. This would occur if all porous materials were loaded prior to using any sealants or paints.

Accurate product loading and a building flush out are essential steps when renovating. Many elements factor into creating a space with good indoor air quality, but knowing what each environment requires, how individual products affect IAQ and the best way to finalize a project are the first and best steps to take when renovating any building for good indoor air quality.