ebuild Blog

The Environmental Protection Agency intends to study whether it needs to address potential health risks of two chemicals found in spray polyurethane foam and used in compounds that seal concrete and finish floors.

The agency said last week it will collect data regarding methylene diphenyl diisocyanate (MDI) and toluene diisocyanate (TDI) and conduct exposure monitoring to help it decide whether it should write rules involving the two products in their uncured form.

Diisocyanates are used to make polyurethane polymers, such as foam mattresses or bowling balls, which consist of fully reacted, or “cured,” polymers. The adhesives, coatings, and spray foam mentioned are uncured and react while in use, making them harmful during exposure.

Diisocyanates can cause severe skin and breathing ailments in people who have been repeatedly exposed to them. The chemicals are also known to cause work-related asthma and, in rare cases, fatal breathing reactions. The Occupational Safety and Health Administration (OHSA) regulates workplace exposures through permissible exposure limits. While there are a number of guidelines and information for professional contractors who work with the chemicals, there is little in the way of guidelines for customers and non-professional people who may be exposed. The EPA will look to consider the risks for consumers exposed to the chemicals in their various forms.

“There has been an increase in recent years in promoting the use of foams and sealants by do-it-yourself energy-conscious homeowners and many people may now be unknowingly exposed to risks from these chemicals,” said Steve Owens, assistant administrator for EPA’s Office of Chemical Safety and Pollution Prevention.

This article was originally posted on ProSales Online.

Under pressure from presiding Federal Judge Eldon Fallon, lawyers for homeowners and for Chinese drywall supplier Knauf Plasterboard Tianjin have agreed to a preliminary settlement of 300 cases of houses contaminated by the defective product. Plaintiffs’ attorneys announced the settlement in a press release October 14 (“Judge Announces Breakthrough Settlement in Chinese Drywall Litigation”). The full text of the settlement agreement is posted at the website of the United States District Court for the Eastern District of Louisiana (“Settlement Agreement for the Demonstration Remediation of Homes with KPT Drywall”).

Under the agreement, crews will remediate 300 homes built with 95% or more Knauf drywall, applying the protocol specified by Judge Fallon in his decisions in earlier bellwether trials held to establish the basic facts of Chinese drywall. In a decision involving Chinese firm Taishan Gypsum Ltd, reported by the Sarasota Herald Tribune on April 9, Fallon had specified a complete replacement not just of the drywall itself, but of any other affected components of the home (“Sweeping drywall ruling finds for homeowners,” by Aaron Kessler).

Under the terms of the October settlement, this same drastic remedy will be applied to 300 houses, with the ultimate goal being to develop procedures suitable for every house contaminated by the Knauf product, reports the Herald Tribune (“A first step in eliminating Chinese drywall,” by Aaron Kessler). “The pilot program … runs lockstep with remediation guidelines established by Fallon in a series of decisions handed down this year,” the paper reports. “They call for essentially gutting the home and rebuilding it to its former condition: replacing all drywall, wiring, copper pipes, the air-conditioning system, fire safety equipment and all damaged fixtures.” Knauf appears to have dropped its earlier efforts to hold out for a less extensive repair job. In addition, the company has agreed to pay for temporary lodging for affected residents, as well as for damage to personal property inside the homes.

But as the Herald Tribune reports, questions remain about how the program can be expanded to include homeowners whose situations vary from the 300 relatively simple cases chosen for the pilot program (“Knauf drywall deal doesn’t take care of everyone yet,” by Aaron Kessler). “For example,” writes the paper, “what happens to people who have remediated their own homes, at considerable expense, with the hope of recouping those costs through the legal process?” Questions also remain about how Knauf will address empty or abandoned houses, whose owners have left because of the unpleasant smell, irritation, or health concerns. In many cases, particularly in economically troubled Florida, homes are subject to foreclosure (sometimes brought on because owners could not afford to pay a mortgage on an empty house, along with the rent on their emergency dwelling.)

And, the paper points out, hundreds, possibly thousands, of houses have a mix of Knauf drywall and some other brand — perhaps domestic, perhaps from another Chinese company. Those houses aren’t included in the pilot program, but any broader program will have to include them in order to fully address the damage created by the faulty material.

This article first posted to coastalcontractor.net.

The 2009 International Energy Conservation Code (IECC) and the 2009 International Residential Code (IRC) have several new mandatory requirements for air sealing in new construction and additions.

Note that these codes apply to new construction where adopted by local jurisdictions. In general, these requirements do notapply to retrofit projects unless the project adds living space to the building or changes the building’s energy load. The existing, unaltered portions of the structure are not required to comply with all of the requirements of the 2009 IECC or IRC.

However, any remodeling work that intends to achieve increased levels of building performance should address air sealing — a high-value way to increase efficiency in existing homes.

New Guidelines

The U.S. Department of Energy’s Building America program has recently developed an air sealing guide for both contractors and consumers. The guide is intended to help contractors explain the value of air sealing to their customers, address important issues associated with air sealing (including ventilation requirements), and to provide technical guidance on key areas that are often difficult to address.

The following checklist and graphic are from Volume 10 in the Building America Best Practices Series“Retrofit Techniques & Technologies: Air Sealing: A Guide for Contractors to Share with Homeowners,”available here [PDF].

Air Sealing List

Air Barrier Completion Guidelines

1. Air barrier and thermal barrier alignment: Air barrier is in alignment with the thermal barrier (insulation).

2. Attic air sealing: Top plates and wall-to-ceiling connections are sealed.

3. Attic kneewalls: Air barrier is installed at the insulated boundary (kneewall transition or roof, as appropriate).

4. Duct shaft/piping shaft and penetrations: Openings from attic to conditioned space are sealed.

5. Dropped ceiling/soffit: Air barrier is fully aligned with insulation; all gaps are fully sealed.

6. Staircase framing at exterior wall/attic: Air barrier is fully aligned with insulation; all gaps are fully sealed.

7. Porch roof: Air barrier is installed at the intersection of the porch roof and exterior wall.

8. Flue or chimney shaft: Opening around flue is closed with flashing and any remaining gaps are sealed with fire-rated caulk or sealant.

9. Attic access/pull-down stair: Attic access panel or drop-down stair is fully gasketed for an air-tight fit.

10. Recessed lighting: Fixtures are provided with air-tight assembly or covering.

11. Ducts: All ducts should be sealed, especially in attics, vented crawlspaces, and rim areas.

12. Whole-house fan penetration at attic: An insulated cover is provided that is gasketed or sealed to the opening from either the attic side or ceiling side of the fan.

13. Exterior walls: Service penetrations are sealed and air sealing is in place behind or around shower/tub enclosures, electrical boxes, switches, and outlets on exterior walls.

14. Fireplace wall: Air sealing is completed in framed shaft behind the fireplace or at fireplace surround.

15. Garage/living space walls: Air sealing is completed between garage and living space. Pass-through door is weather stripped.

16. Cantilevered floor: Cantilevered floors are air sealed and insulated at perimeter or joist transition.

17. Rim joists, sill plate, foundation, and floor: Rim joists are insulated and include an air barrier. Junction of foundation and sill plate is sealed. Penetrations through the bottom plate are sealed. All leaks at foundations, floor joists, and floor penetrations are sealed. Exposed earth in crawlspace is covered with Class I vapor retarder overlapped and taped at seams.

18. Windows and doors: Space between window/door jambs and framing is sealed.

19. Common walls between attached dwelling units: The gap between a gypsum shaft wall (i.e., common wall) and the structural framing between units is sealed.

—The Department of Energy seeks to offer comprehensive, whole-house technical information to the industry and consumers to encourage energy-efficient remodeling and retrofit practices. Click here for a variety of resources, including case studies of successful retrofits in all climate zones, energy code and tax incentive information, and more.