Reducing formaldehyde in the home

The main source of formaldehyde in new homes is pressed wood products. MDF is medium-density fiberboard and HDF is high-density fiberboard - both are a mix of wood fiber and formaldehyde resin as the adhesive.

Some flooring types (like some engineered woods and all laminate) have a backing of HDF or MDF which is pressed with formaldehyde. Those do off-gas noticeably.

The glues for installing flooring (if it's a glue-down) and much better these days and usually don't off-gas formaldehyde.

There are some other more unusual flooring types that can use formaldehyde as a glue, some cork floorings are an example. (Though not all. The best ones are made with PET glue and are just about zero-VOC).

MDF or HDF fiberboards are also used in doors. Low-end doors are hollow and have a skin of HDF, higher end doors have an interior of MDF.

Baseboards are also made from MDF, almost always, unless it's an upscale house and solid wood is being used.

One last place you will find pressed wood products is in cabinets. Low-end cabinets and vanities use particleboard, which is a pressed wood product with a lower density (also made with formaldehyde glues). Higher-end cabinets almost always have MDF, at least for the center piece. Some cabinets also use HDF for the backing.

It is possible to get cabinets in solid wood but they don't come in all styles.

In the bathroom, for the vanity, you have the same material options, but it's even more rare to find solid wood vanities. I list the options I have found via that link. Those are the main interior elements that off-gas formaldehyde in new homes. When you add furnishings and paint you should select the more eco-friendly options. A lot of furniture is made with particleboard, MDF, and some HDF too. Fabric treatments can also off-gas formaldehyde and other chemicals.

There are a lot of paints that don't off-gas at all once they are cured (usually at two weeks but really after 24 hours the VOCs are imperceptible).

Oil-based paints are higher off-gassing coatings, but you can use a water-based alkyd paint on the trim and doors instead and that will improve your air quality. If that is still too high in off-gassing for you, look at the natural linseed oil paints or just a regular acrylic paint on the trim and doors.

Corinne Segura is a Buiding Biologist who helps folks create healthy homes at www.mychemicalfreehouse.net