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Insulation and Your Home: Fact Insulation And Your Home: Fact Sheet Health Considerations Environmental & Occupational Health Assessment Program September 2014 You may be thinking about adding new insulation to your existing home if your home is drafty, or you are looking for ways to save money on energy costs. There are many different types of insulation products in the market place, and many different ways to insulate a house. The type of insulation you choose and the way it is installed may affect your health. The goal of this fact sheet is to help you to become an informed buyer. You will learn to examine three things that can impact your health: 1. Chemical ingredients 2. How dampness and temperature extremes affect your insulation choices 3. Why using an experienced installer is so important. This fact sheet focuses on the most commonly used insulation products in existing houses in the Northeast: synthetic polymer foams like spray polyurethane foam (SPF), mineral wool or fiberglass batts, and blown in cellulose. If you are building a new house or addition, there may be additional insulation products for you to consider. Connecticut Department of Public Health 410 Capitol Avenue, Hartford, CT 06066 http://www.ct.gov/dph Insulation and Your Home: Health Considerations September 2014 Page 2 Exposure to some insulation products can cause 1. Ingredients certain health effects if the product is mis- Many building materials including thermal handled, mis-applied, or if the wrong product is insulation contain fire retardants. Certain classes used in certain environments. Common of insulation products may also contain symptoms may include irritated, itchy, watery, or chemical additives such as colorants, blowing burning sensation of the eyes, nose, or throat, or agents, catalysts, and binding agents. Finding itchy skin or skin rashes. Occasionally, some out what is in the insulation may influence your people report breathing difficulties, especially if choices. If you or any household members are they are asthmatic or have other breathing sensitive to any of these chemical ingredients, disorders. Rarely, some people have reported you may choose to look for a different symptoms like nausea, headache, and confusion/ formulation or type of insulation. difficulty concentrating. Sometimes there is an unpleasant odor that does not go away; in some To find out what chemicals are in the insulation of those cases, people have found it difficult to product under consideration, go to the stay in the house. manufacturer’s website and download a copy of How You Can Become Exposed the Material Safety Data Sheet (MSDS). Manufacturers are required to list ingredients There are two main ways that you can become and quantities, as long as they are not exposed to insulation: proprietary ingredients. You can also download a product information sheet (also called a sell Breathing chemical ingredients in the air sheet or cut sheet). Here are some of the This is usually the result of chemical off-gassing. chemical ingredients you might see. A small amount of off-gassing is normal. It should go way within a few days. If it doesn’t, Formaldehyde there may be a problem with the insulation or Can cause eye, nose and mouth irritation the way it was installed. in sensitive people Breathing or skin contact with insulation dusts Can cause respiratory problems There is usually a fair amount of dust generated including acting as an asthma trigger by cutting dried foam or by simply handling Off-gassing is increased in hot, damp loose, fluffy cellulose, or fiberglass, which can environments shed tiny pieces of glass that can be itchy. The Found in some fiberglass insulation insulation contractor should clean thoroughly products after they are finished. This includes using a Main component in Urea Formaldehyde vacuum with a HEPA filter to pick up the dust. Foam Insulation (UFFI)- improper This should be done before the household installation in 1970’s caused members come back home. formaldehyde Connecticut Department of Public Health Environmental & Occupational Health Assessment Program 860-509-7740 http://www.ct.gov/dph/ieq Insulation and Your Home: Health Considerations September 2014 Page 3 off-gassing and respiratory complaints, may be more expensive than the borate- leading to a widespread UFFI ban in the ammonium sulfate mix, but may release US and Canada. fewer odors. Fire Retardants Catalysts Protecting your home from fire is important. Catalysts are added to the mix of Codes require fire retardants in most types of ingredients in foam insulation products to thermal insulation. enable the chemical reaction to occur to Foam Insulation Products: make the foam. Some catalysts are made with a class of chemicals called amines. Certain fire retarding chemicals are These can off-gas and produce a fishy or routinely added to flexible and rigid foams. sickenly sweet odor if the foam does not Some of these chemicals do not bind to the harden or cure properly, and this off- finished insulation material. They are gassing can continue for many weeks. The continuously released into the environment resultant odor has made some people ill. throughout the life cycle of insulation. Some have been implicated in disrupting normal thyroid hormone function, nervous 2. Environmental Conditions system development, and are potentially Your choices for types of insulation should carcinogenic. be guided by which area of the house you plan on insulating. Cellulose Insulation: Attics: Ammonium sulfate and boric acid are fire retardants commonly found in cellulose If you plan on adding insulation to your insulation. Occassionally, the ammonium home, you can realize the biggest energy sulfate can off-gas and produce an odor. In savings by insulating your attic. Common damp environments, it can also form attic insulation choices include loose fill corrosive byproducts that can degrade cellulose, SPF, and mineral wool/fiberglass metal that it comes in contact with. This batts. Attics can present challenges because appears to be more of a concern in hot, of the large variations in temperature in the high humidity environments like the Northeast. That and moisture will narrow southern part of the US. It is possible to types of insulation suitable for attics. A cost purchase an all-borate cellulose product. It effective approach is to first seal floor Cellulose Spray Insulation Polyurethane foam Insulation Connecticut Department of Public Health Environmental & Occupational Health Assessment Program 860-509-7740 http://www.ct.gov/dph/ieq Insulation and Your Home: Health Considerations September 2014 Page 4 penetrations with foam, then cover the floor flow through gable and/or ridge vents and with cellulose or batt type insulation. through soffits by adding baffles in rafter Temperature Extremes: bays. Basements & Crawl Spaces Attics get both very hot and very cold in the Northeast. If you choose spray foam to Many of the same principals apply to insulate the attic, make sure that the specific basements and crawl spaces. Humidity will SPF product used is designed to withstand dictate the type of insulation that will work large temperature swings. Closed cell SPF in the space. Certain types of SPF should is a good choice for Northeast attics not be used in damp basements or crawl because of insulating and vapor retarding spaces, because they will not cure properly. properties. Manufacturers usually make a This can lead to extended periods of off- number of formulations. Check with them gassing (weeks to months) , resulting in to ensure the right one of their products is odors and possible health impacts in some being used for your environment. If not, people. Check with the manufacturer to there could be problems with curing, find out if the specific formulation you are leading to off-gassing, unpleasant odors, interested in is appropriate for your and possible health related effects. basement. Vapor Barriers-Not Always Needed Do not install anything with a vapor barrier If mineral wool/fiberglass batts (like mineral wool/fiberglass bats) without are chosen, they can be consulting with a knowledgeable person purchased with a variety of about the specifics of your space. If backing materials like kraft fiberglass batts or other vapor barriers are paper and reflective foil. These used, make sure the backing material/vapor backings act as a vapor barrier. barrier is facing towards the inside of the house to prevent moisture from Before buying, check with a Exterior wall -Fiberglass knowledgeable source to see batts between studs, accumulating. if a vapor barrier is indicated vapor barrier facing living space. It is ok to use fiberglass in dry basements, for your area, and if so, make but it should not be used in crawlspaces sure that the backing is facing towards the under the house. Fiberglass subjected to living space. Otherwise, you could end up dampness, humidity, or weather can with a mold problem in the attic. become a dirt trap and breeding ground for Ventilation bacteria and mold. Closed cell spray foam or rigid foam would be a better choice for It is important to maintain air flow through crawl spaces where humidity/exposure to the attic space to prevent moisture weather are concerns. accumulation. When installing any type of insulation in the attic, allow for natural air Connecticut Department of Public Health Environmental & Occupational Health Assessment Program 860-509-7740 http://www.ct.gov/dph/ieq Insulation and Your Home: Health Considerations September 2014 Page 5 Side Wall Insulation It is advisable to choose an installer who has been in business for a long time. If you do The most common choices for a retrofit job have any problems, you want to be able to have are injection foam or blown in cellulose. them come back and work with you to resolve The installer will drill a series of horizontal the problem. See page 6 for some common holes from either the inside or outside.
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