Vinyl Window Offgassing

May 23, 2014 by Debra Lynn Dadd

Question from Terry

Debra, I found this "green" website discussing vinyl windows, saying that they do *not* affect indoor air quality. Would you read this and tell me what you think? I am about to buy a vinyl sliding door and I am concerned. But this website says there is nothing to worry about.

www.greenhomeguide.com/askapro/question/i-am-considering-replacing-aluminum-windows-and-have-heard-that-vinyl-can-offgas-forever-is-this-true

Debra's Answer

Well, that's an interesting article.

I like Green Home Guide a lot, but I don't know why she overlooked the most obvious thing about vinyl: it's toxic!

For many years, Greenpeace has had a campaign to eliminate PVC. They have a PVC Alternatives Database that lists windows and doors that are PVC-free.

They say, "this commonplace plastic is one of the most toxic substances saturating our planet and its inhabitants. PVC contaminates humans and the environment throughout its lifecycle: during its production, use, and disposal. Few consumers realize that PVC is the single most environmentally damaging of all plastics."

It is also not recommended to paint vinyl doors and windows, so paint wouldn't be the most toxic part. Nor would paint necessarily block any outgassing.

Here's another good article: PVC, the Poison Plastic

Here's another article about PVC: Green Building Advisor.com:
Pro/Con: Vinyl is Lethal

This article says

Vinyl is the only major building material in which phthalates are used extensively, and it accounts for about 90 percent of total phthalate consumption. Phthalates are not chemically bonded to the plastic but are merely mixed with the polymer during formulation. They therefore migrate out of the plastic over time into air, water, or other substances with which vinyl comes in contact. Phthalate levels in indoor air in buildings with PVC are typically many times higher than in outdoor air. Phthalate accumulation in suspended and sedimented indoor dusts is particularly high, with concentrations in dust as high as 1,000 parts per million.

Because phthalates are semi-volatile organic compounds (SVOCs), not volatile organic compounds (VOCs), they are not accounted for in most indoor air quality (IAQ) tests, which focus only on VOCs. Thus, vinyl products can obtain IAQ certifications even though they leach phthalates, whose contributions to reproductive-system impairment include infertility, testicular damage, reduced sperm count, suppressed ovulation, and abnormal development and function of the testes and male reproductive tract in laboratory animals. They are known carcinogens in laboratory animals.

And now, here is the evidence that vinyl windows and doors DO outgas. This article is from a website for building inspectors, to locate and fix problems: InspectAPedia: Guide to Plastic, Vinyl Odor Source Diagnosis—Vinyl Siding & Plastic Windows, Flooring & Other Sources. They cite vinyl windows as a source of chemical order, especially when heated. This is a pretty interesting website with lots of toxics information about building materials from real life observation.

Toxic-Free Q&A

These are archives of Q&A asked by readers and answered by Debra Lynn Dadd (from 2005-2019) or Lisa Powers (from 2019-2020). Answers have been edited and updated as of December, 2020.