The title of this article should be changed to: …may lead to poor indoor air quality.
Everyone in the energy efficiency world is familiar with the phrase “build tight, ventilate right”. BPI and home performance programs emphasize testing for radon and if necessary installing a radon vent fan as well as makeup ventilation system for tightly sealed homes.
The other interesting part of this article is that it is based on a model and some statistical info from England. No reference of actual cases or scientific studies in the USA.
Another thing they mention is installing better insulation. However, that only addresses conductive heat loss. The convective heat loss from unsealed air gaps in your home causes drafts and results in comfort complaints. In taller buildings air sealing saves a great deal of money.
This is a misleading article using a scare tactic.