Housing and Health

We can control many of the sources of pollution that otherwise can make asthma worse or can make people sick by good design, construction, renovation, maintenance and operation. In addition, what we bring into our homes, how we live in our homes and how we clean and maintain our homes also affect the quality of the air in our homes.

Before You Design, Build or Renovate

The principles for a healthy home are the same for all types of construction:  rehabilitation, new construction, low-rise, high-rise, single family or multifamily.

The design and construction options for rehabilitation are limited by conditions of the salvaged building and equipment and extent of the rehabilitation.  Despite the limitations, the same principles apply to whatever work is done as part of the rehabilitation.

There are seven principles to a healthy home. Ideally, a healthy home is:

• Dry
• Pest free
• Clean
• Toxic chemical free
• Well ventilated
• Comfortable
• Combustion by-product free

Not all principles can be controlled by design, construction, renovation and maintenance. How we live in a home also matters. And not all principles can be achieved perfectly or completely or practically — they are goals.

Applying the principles for a healthy home to design, construction, renovation and maintenance does not have to result in significant cost increases.  By understanding the interactions between building systems we can identify cost saving trade-offs that improve building performance and improve control of interior conditions such as comfort — particularly temperature and interior humidity. Additionally, many principles result in reduced call-backs and warranty claims.

Improve building envelope        Costs more (+)

Downsize mechanical system    Costs less (-)

                                                   =  Cost remains the same

Dry  Water and humidity support the growth of mold, insects, rodents and dust mites.  Keeping a home dry controls mold and pests, and discourages dust mites.

Dust  Dust is a source of contaminants, provides food for some of the pests that trouble people in buildings and physically damages flooring. The amount of dust in a building can be reduced by ensuring it’s clean before occupancy, designing it to stop tracked-in dirt at the door and using finishes and equipment that are easy to clean and maintain.

Well ventilated  Ventilation provides a mechanism to remove pollutants and control humidity. Windows that open and fans that run control pollutants.

Combustion by-product free  Combustion by-products — such as carbon monoxide, sulfuroxides, nitrogen oxides and soot — should not be in a healthy home. Furnaces, water heaters and fireplaces that burn fuel must vent to the outside. Stoves, ovens and cook-tops that burn fuel must be used with fans that vent the combustion by-products to the outside.

Pest free  Pests can lead to allergic reactions and to the use of pesticides.  Food and water attract pests. Controlling food and water helps to minimize pests.

Toxic chemical free  We are surrounded by chemicals, so no environment can be made completely chemical free. But we can control our exposure. Many things found in houses can be toxic in large doses. Some we can control by design and construction such as selecting materials that don’t smell or release chemicals. Others we can control by the way we live in the home. For example, many cleaning compounds, pesticides, oil- or alkyd-based paints and solvents can lead to problems. Many containers that these products are stored in slowly release the chemicals. It is best not to store these products inside. When in doubt, safely dispose of these products. Many municipalities operate household chemical disposal programs.

Comfortable  Uncomfortable homes can make people take action that makes a home unhealthy.  Too hot or too cold is usually uncomfortable. Operable windows can control heat and provide ventilation.  But sometimes when it is too cold windows will not be opened, and sometimes when it is too hot even opening windows will not cool the home enough.

And what happens when people are scared to open windows?

Sometimes the outside air has pollutants such as ozone and pollen that may require some people to keep windows closed and filter incoming air.

If people are cold they won’t ventilate their home.  If people can’t afford to heat their home they won’t ventilate their home.

A healthy home has windows that open and fans that run — but a healthy home must also be healthy when windows are closed because it is too cold, because it is too hot, because people feel unsafe or because pollutants are present in the outside air.

Uncomfortable can also be too dry or too humid.

When a home is uncomfortably dry, people often humidify. Many times when people humidify they can over-humidify.  Over humidifying may result in mold and mites and other pests. A properly built or renovated home will not require a humidifier to be comfortable.

When a home is uncomfortably humid, particularly in the summer and fall, it may require a dehumidifier or air conditioner.  Even properly built or renovated homes may require a dehumidifier or air conditioner to control humidity in the summer and fall to be comfortable and healthy — particularly in the southeast.

Factors That Must Be Controlled for a Healthy Home

To address the seven principles for a healthy home, the design, construction, renovation and maintenance must control the following factors:

• Water

Rainwater control

Groundwater control

Plumbing

• Dust

Entry control

Lead dust control

Cleanable surfaces

Filtration

• Air

Big holes and building boundaries

Cold surfaces

Indoor humidity

Airborne pollutants

Pressure changes

• Creatures

Keeping them out

Reducing food and water

• Combustion

Combustion appliances

Garages

Smoke