This article is an overview of various insulating materials and methods used throughout the world. Special attention is placed on recent findings related to health issues as they relate to insulating materials and methods. Also, you will find little-known ways to improve sustainability with insulation.
Codes change because energy costs change. As the costs increase, so do the codes. With the fast rising rate of fuel costs, new codes are always implemented throughout the United States. The most recent insulation code change was in 2003. That means you can have a rather new home, yet be under insulated in the attic. In our zone in Michigan, building codes in 2003 changed from R-19 to R-30 for attics. It took another 3 years for Michigan to catch up to national standards of R-49.
Environmentally Friendly Insulating Products & Methods
- Cellulose: Made of recycled newspapers and wood pulp, fire-retardant and mold retardant chemicals are added to make this product a safe insulating product. See our list of cellulose distributors.
- Fiberglass: made from sand, in some products minimal amounts of urea formaldehyde is used. See our list of fiberglass distributors
- Open Cell: 3.9 rs per inch. This type of foam includes soy and cementitious www.icynene.com | www.airkrete.com
- Closed Cell: 7 rs per inch. This polyurethane foam now includes a soy based product www.biobased.net
- Rockwool: Made from recycled furnace slag, this material is very dense and has excellent acoustical properties.
- Cotton: Made of 75% recycled blue jeans, a fire-retardant chemical is added. www.insultechnology.com |www.bondedlogic.com
- Wool: sheep’s wool, oils from the wool are stripped to make it fire-retardant
- Reflective radiant barrier: foil used particularly in the South.
- Mushrooms!!: In 2007 mushrooms were introduced as an eco-friendly insulating material. http://www.physorg.com
Older insulating materials, no longer used, but commonly found in houses
Even though what were considered environmentally friendly materials in the past, the following materials carried with them certain hazards.
- Vermiculite: This material is mined from various locations. A North American mine, Libby, Montana had a contaminated mixture of asbestos with their vermiculite (aka Zonolite).
- Urethane Foam: Popular in the ’70s, this was discontinued because of the toxic fumes emitted during house fires.
There is such a thing called Sick Building Syndrome and Building Related Illness:http://www.epa.gov/iaq/pubs/sbs.html
The part insulation played in negatively affecting health.
- Asbestos Asbestos is dangerous when it it becomes airborne. The fibers, when disturbed, can enter the lungs. Mesothelioma, has become such a hot topic that a new industry of lawyers has been created: mesothelioma attorneys.
- How do you prevent illnesses such as mesothelioma?
- Locate possible places where asbestos was commonly used. Pipe wrap, Asbestos siding on older homes and as insulation in attics (Zonolite).
- How to identify and fix an asbestos problem:
- Only owners of noncommercial, residential buildings can legally fix an asbestos problem without professional help.
- Stabilize the asbestos by installing blown insulation on top.
- Vermiculite insulation be left undisturbed in your attic. Due to the uncertainties with existing testing techniques, it is best to assume that the material may contain asbestos.
- You should not store boxes or other items in your attic if retrieving the material will disturb the insulation.
- Children should not be allowed to play in an attic with open areas of vermiculite insulation.
- If you plan to remodel or conduct renovations that would disturb the vermiculite, hire professionals trained and certified to handle asbestos to safely remove the material.You should never attempt to remove the insulation yourself. Hire professionals trained and certified to safely remove the material. http://www.epa.gov/asbestos/pubs/insulation.html
- How do you prevent illnesses such as mesothelioma?
- Mold/Lack of Ventilation
- Symptoms that indicate there is a mold problem — reoccurring illness, asthma, fever, cough, chest tightness, irritation.
- Use of polyethylene film contributes greatly to mold issues. Why? It attracts moisture and does not let vapor laden water escape the living area.
- If you have beautiful, large icicles coming from large ice dams in your gutters, you most likely have a ventilation problem that will indicate you are a candidate for, if not already a mold grower.
- Some manufacturers state that their products resist mold. However, mold can grow on any surface. It can grow on a dinner plate. Mold will grow on any surface/material if it is dark and damp. Lungs are dark and damp, getting mold spores in your lungs is a huge health issue.
- Therefore, preventing mold means you need to have good ventilation and completely clean up flooded areas. If your wall systems get flooded, you need to claim this on your insurance and get professional wall-dryers involved [1. Sources: http://www.postgradmed.com/issues/2003/06_03/fung.htm]
- Urea Formaldehyde: Urea Formaldehyde is used in a wide variety of building products. It is especially found in particle board. In the 1970s, foam insulation systems contained high amounts of UF. Those particular foam systems have been discontinued for a number of reasons including Sick Building Syndrome, cancer (in industrial workers), toxic gases during a house fire would often kill the inhabitants before they were overcome with smoke. [2. For more information see: www.hml.com/docs/HML_SickBuilding1998.pdf | www.cancer.gov/cancertopics/factsheet/Risk/formaldehyde ]
Insulation issues that have improved health
Energy reduction has improved health and reduced mortality rates.
The five states with the greatest total energy savings are (in order) Michigan, Texas, Nevada, Virginia and Illinois. These states account for 32% of the net total primary energy saved throughout the country, with the top half of the states accounting for 82% of the total energy savings potential.
Michigan is leading in total energy savings, not simply because of new construction codes, but homeowners are revisiting their home energy savings:
….As in the regional analysis, this clearly demonstrates that the states with greatest per-unit energy savings are not necessarily the states with the highest rates of new construction. [3. Harvard School of Public Health, Department of Environmental Health, Integrating Risk Assessment and Life Cycle Assessment: A Case Study of Insulation. 2002.]
In the 70’s energy companies encouraged the use of polyurethane vapor retarders. This led to mold problems. Introduction and requirement to use house wraps has remarkably improved the industry. House wraps (i.e., Tyvek) prevent moisture penetration, but allow moisture-laden vapor to escape. Moisture does not get trapped in the walls.
VOCs (Volatile Organic Compounds)
When materials cure in new building structures, they give off gases. These can be toxic when inhaled or when they come in skin contact. See this informative site related to reducing exposure to and minimizing the effects of VOCs (like formaldehyde) in the home.
A better understanding of ventilation in attic systems. In the 60’s the popular style of housing involved low roof pitches. The ventilation through the attic spaces was nil. Perhaps a gable vent, but for the most part, ventilation in the older style homes was not a consideration. Thus, homes suffered black mold issues and poor insulation performance.
Since the 80’s, both roofers and insulators developed a ventilation system to improve air flow in the attic.
Some insulating materials are fire-retardant by nature because they are made of materials that do not burn: unfaced fiberglass, rockwool, ceramic
Other materials are naturally flammable, so manufacturers add fire-retardant chemicals: cellulose, foam.
In all, our opinion of the fire-retardant issue is moot. In most, framed houses, there is very little that is fire-retardant, so why focus on insulation? Insulation materials will not keep a house from burning down when the wall systems are made of drywall, lumber and often wood siding.
Areas to check in your home
- Ceiling: This should be the first place you check. Though your walls may lack insulation (dealt with in the next point), heat loss is vertical and your attic should be addressed first. You are looking for the proper depth. What is the proper depth? Use this tool to determine what current standards are for your area. If you walk through your attic, wear shoes with excellent tread. Tennis shoes become very slippery when you step on insulation.
- Roof: When your roof is covered with snow, look for melting spots. Indicates a lack of insulation, separated ductwork, a bathroom vent has separated or an attic furnace has lost its covering.
- Cabinets or stairwells: Are they cold? Insulation may have collapsed into the cavities.
- Frost or moisture in ceiling. Insulation may not exist or has been pulled away by people working in the attic or animals nesting. Always remove wet insulation and replace with new. When adding insulation, blown in insulating material is best. It will fill all the gaps.
- Walls: Do you have insulation or not? If your home was built in the ’60s or later, you most likely have at least R-11 in the walls. Adding more insulation to walls that have an R-11 will not produce enough savings. If you have an older home and question whether you have insulation, simply remove an electrical face plate and look in the gap next to the plug to see if insulation exists.
- Rim Joists (aka Bonds): Until the ’80s, rim joists were rarely insulated. Simply fill the void with unfaced insulation.
- Recessed Lighting in Ceiling: Older fixtures breathe into the attic space. Thus, they bleed cold air into the room. Replacing these with new fixtures ($20) will decrease leakage. Make sure they are IC rated.
- Electrical Outlets: Remove the face plate. If you feel a draft, purchase an electrical outlet gasket. Do not fill the gap around the outlet with foam as it could raise the risk of fire. The gasket will do a much better job than foaming around the outside of the plug.
- Attic Access: We often find that either the insulation has been moved away from the hole or never existed in the first place. Either place a batt of insulation over the hole or glue 4” of foam to the access panel. A staircase access can be covered by a box made of foam.
- Crawl Spaces: Common practice is to insulate the floor above the crawl with batts. Our recommendation is, if heat can be introduced into the crawl space, then insulate the walls, not the floor. Your floor will be considerably warmer.
- Finishing your basement: It is common practice to put polyurethane film against the basement wall. Do not do this. The plastic attracts moisture and will rot the bottom plate. This is a common mold causer. Stud or use furring strips. Use fiberglass batt or foam board to insulate the wall. If you do not intend to use a wall system, you can have a vinyl, fire-rated insulation nailed into the wall. Owens Corning developed a pre-made wall system which is excellent, yet comes with a hefty price.
- Living spaces above garages: Insulate the garage doors with foam inserts like these.