Category A Healthy. House

John Banta was called to the home of a woman who was employed as a cook by the television in­dustry. Her task was to create samples of the same recipe in various stages of preparation, from raw ingredients to oven-ready mixtures to finished product. The prepared foods were then delivered to the television studio so a celebrity on a culinary arts program could demonstrate the recipe.

During the investigation, John discovered that his client was being exposed to an unex­pected occupational hazard. The orange-colored tile used for her counter was glazed with uranium

products for interior finishes and cabine­try (see Resource List for products)

• Medex or Medite II: A medium density fi – berboard manufactured without formal­dehyde

. Multi – core: A low-emissions plywood with a variety of hardwood veneers

• PureKor: Specify their formaldehyde-free board

• Roseburg SkyBlend Particleboard: Sci­entific Certification Systems certified, low emissions, certified recycled content, no urea-formaldehyde added during manu­facturing process

• Temstock-Free: No added urea-formalde­hyde particleboard underlayment and in­dustrial-grade particleboard

• Terramica: Scientific Certification Sys­tems certified no added urea-formalde­hyde particleboard underlayment and industrial-grade particleboard

• Tru-Spec: Line ofurea-formaldehyde-free, millwork-quality wood strand engineered

oxide, a highly radioactive substance that was making the numbers on the Geiger counter spin too fast to count. For over 30 years this woman had worked at a radioactive counter, slicing, dicing, mixing, and arranging her creations.

When she learned of the radioactivity, the cli­ent revealed to John that she had recently had a precancerous lesion removed from her intestines. Her surgical scar was located at the level where the counter pressed against her while she cooked. The client was advised to have her countertop re­placed. Her physician concurred.

wood products for interior wood finishes and cabinetry, GreenGuard certified

Alternatives to Hardwood

Because hardwoods take a long time to grow and are therefore not as sustainable as faster growing alternatives, you might consider the following healthy alternatives to hardwood for your finsh carpentry and cabinetry:

• Alio wood: Hardwood lumber substitute manufactured from faster growing soft­woods and agri-based materials

• Environ Biocomposites: Line of formal­dehyde-free, agri-based sustainable panel products for interior finishes and cabinetry

• Bamboo: Refer to Division 9 for bamboo sources

Countertops

The ideal countertop material for a healthy home would have a solid, nonporous surface that is stain – and scratch-proof. It could be attached by mechanical means directly to the cabinet boxes, thus avoiding the need for un- derlayment and adhesives. It would be beauti­ful, inexpensive, and manufactured in a variety of colors. Unfortunately, all of these character­istics are not found in combination in a single countertop option. Chart 6.1 reviews the most common countertop materials and outlines specification concerns for each.

Chart 6.1: Countertop Comparisons

Medium density fiberboard (MDF) is sheet – good material used for interior nonstruc­tural applications such as cabinetry boxes and shelving. Traditionally, MDF has been bound with urea-formaldehyde-based glues, making their use unacceptable in a healthy house. The following products are formaldehyde-free and may be available laminated with plastics or hardwood veneers:

• Arreis: Scientific Certification System cer­tified medium density fiberboard with no formaldehyde added in the manufacturing process

• Glacier Clear: Scientific Certification Sys­tem certified medium density fiberboard

with no formaldehyde added in the manu­facturing process

• Medex or Medite II: Scientific Certifica­tion System certified medium density fi­berboard manufactured without formal­dehyde

• Wheatboard or Wheatstraw: Medium density fiberboard made from straw fiber and containing no incremental formalde­hyde emissions

Cabinets

Although the drawers and doors on cabine­try are often made of solid wood, the boxes or cases are usually composed of particleboard, interior-grade plywood, or melamine, which has a particleboard core that is exposed where holes have been drilled for adjustable shelving. Cabinets are most often finished with solvent – based finishes that may outgas high levels of VOCs for several months.

Because standard cabinetry contributes significantly to poor indoor air quality, it is not acceptable in the healthy house. You will pay more for healthier cabinets, but in terms of indoor air quality, this is money well spent. If your budget is tight, we suggest you explore strategies that will reduce the amount of cabi­netry necessary. For example, you may choose to consolidate some of your kitchen storage in a pantry area, or to use attractive solid wood open shelving for dishes or cookware as a less expensive alternative replacing some of the upper cabinets.

Finishes on wood cabinet doors and draw­ers are commonly solvent-based applica­tions that will take many months to fully cure. Some of the lacquer finishes, although odor­ous when first applied, will completely cure before they are brought to the jobsite and will not require refinishing for many years. If these are applied in quality controlled, well – ventilated shops, they may be worth consid­ering. Ask for a recently applied, dated sample to help make your determination. Low-VOC, water-based finishes that are more suitable for jobsite or factory application are listed in Di­vision 9.

As cabinetmakers are becoming more fa­miliar with the need for healthier cabinetry, and as low-VOC finishes and materials be­come available, the price gap between stan­dard and healthy cabinets is decreasing. The following companies manufacture formalde­hyde free or low emissions cabinetry:

• Cervitor: Distributors of metal cabinetry with a baked-on enamel finish that may be used with metal or solid wood doors and drawers

• Core Home: Cabinets manufactured to European Ei emissions standards with FSC certified products

• Humabuilt Wheat Core Cabinets: Press ed wheatboard boxes, premium-grade woods and veneers assembled with ultra-low – VOC adhesives and finishes, free of syn­thetic formaldehyde

• Neff Cabinets: Manufactured cabinets with a 98% reduction in formaldehyde content

• Neil Kelly Cabinets: Cabinetry system designed to meet the needs of the chemi­cally sensitive, with cores of wheatboard or Medite II with wood veneers, and a wide variety of door and case veneers. Door and drawer fronts available with certified woods, prefinished with AFM clear sealers or paints.

For all options, specify the use of a solvent-free carpenter’s glue in the fabrication process.

The following products are formaldehyde – free sheetgoods that can be used for making cabinet boxes:

• Environ Biocomposites: Line of formal­dehyde-free, agri-based sustainable panel

CASE STUDY 6.2

Many manufactured composite board prod­ucts designed for interior use contain urea – formaldehyde binders. They outgas form­aldehyde for many months and contribute significantly to the indoor pollution level. In standard construction, these interior-grade

composites are used in many finish applica­tions including cabinetry, molding, shelving, and trim. They should not be used in a healthy home. The following maybe specified:

• No sheetgoods or trim pieces containing urea-formaldehyde shall be used.

• Exposed interior finish wood shall be comprised of solid wood and finished with a low-VO C finish as specified in Division 9.

• Where sheet goods are used, choose one of the low-emission boards listed in the section on cabinets, or exterior-grade ply­wood that has been aired out, thoroughly sealed on all edges and surfaces with an acceptable vapor barrier sealant, and fin­ished with one of the paints specified in Division 9.

• Trim pieces shall be milled of solid wood or made of formaldehyde-free composites such as Medite II or equal.

Roof sheathing is placed on top of roof fram­ing members and under the roofing. As with exterior sheathing, exterior-grade plywood or OSB is most commonly used for this purpose. Unlike wall sheathing, roof sheathing will be exposed to high temperatures and will there­fore be subject to more intense outgassing. Roof sheathing usually has less time to air out in place since it is roofed over as soon as possi­ble to avoid water damage from precipitation. We therefore recommend that plywood, if used, be stickered and aired on site. We do not recommend OSB because it can develop mold and deteriorate more rapidly if it happens to get wet. When roofing members are exposed to the interior, as is often the case when beams or vigas are used, solid wood or tongue-and – groove planking is commonly used.

For sloped roofing, when structural condi­tions permit, purlins or skip sheathing maybe acceptable in place of solid sheathing. Purlins are wooden members spaced to receive metal roof panels, while skip sheathing consists of solid wooden members spaced more closely together for shingle and tile roof applications. Both purlins and skip sheathing eliminate the need for sheet goods and allow ample air movement to ventilate the roof space. How­ever, they do not provide the shear strength that plywood provides and their use must also be weighed from an engineering standpoint.

Where a continuous air barrier is installed be­tween the framing members and the living space, the choice of sheathing material is less crucial.

Consider the following guidelines for in­clusion in your specifications:

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• The use of solid wood boards, tongue – and-groove board, solid wood skip sheathing, or purlins is preferred where structurally acceptable.

• CDX-grade plywood, when used for roof sheathing, should be purchased as far in advance as possible to allow time to air
out. Provide protection against moisture damage.

• Provide a continuous air barrier on the inside face of the ceiling assembly as out­lined in Division 7.

Exterior sheathing in wood frame construc­tion is attached to the outside of the frame and makes up the surface to which the exte­rior finish is applied. Before manufactured sheet goods such as plywood were available, ix or 2x material was nailed to the studs for this purpose. In standard wood frame construc­tion today, exterior-grade plywood or OSB (oriented strand board, also known as wafer – board) is typically used as exterior sheath­ing for the entire building or at corners where shear strength is required. These materials contain varying degrees of formaldehyde and isocyanates and do not have the longevity of solid wood products.

Many problems with the use of OSB in roof and wall sheathing have recently been iden­tified. In fact, one prominent manufacturer was the subject of a class action suit. When the board gets wet it is vulnerable to fungal invasion and rapidly deteriorates. Asphalt – impregnated fiberboard or asphalt-sheathed insulating board is commonly used as infill between the corner shear panels. Since asphalt

is a known carcinogen, we believe that any ex­posure level is too high when other alterna­tives exist.

When an air barrier or airtight drywall as­sembly is used on the interior face of a wall, sheathing material will not have as great an impact on the indoor air quality as the ma­terials exposed to the interior. Moreover, the sheathing will have had several weeks in place to air out before it is covered up. In a perme­able or breathing wall system, where vapor barriers are eliminated with the intent of al­lowing vapor movement through the wall, the type of exterior sheathing must be more carefully considered in terms of both perme­ability and harmful chemical content. The fol­lowing maybe included in your specifications to reduce the pollution generated by exterior sheathing: [9]

• non-odorous foam boards such as bead board

• AdvanTech: very low emissions, dura­ble composite wood sheathing for walls, floors and roof

Solid beams, round logs, or 2X joisting are commonly used for shorter roof spans. Man­ufactured trusses, typically made of compos­ite wood products and assembled into profiles engineered for strength, are commonly used for longer spans. They have several advantages over solid lumber. They are less expensive, use wood resources more efficiently, have greater span capabilities, provide a deep pocket for roof insulation, and can be fabricated with a built-in slope for flat roof application.

Truss joists, commonly called TJIs, are manufactured beams containing either ply­wood or dimensional lumber for top and

bottom chords, and either plywood or press – board for the webs. Because they are a very cost-effective way to frame large spans, truss joists are widely used in residential construc­tion. The members are subjected to heat dur­ing manufacturing, which helps cure them, reducing the quantity of VOCs they emit into a new home. A small amount of formaldehyde remains. In new home construction, the cu­mulative effect of several low emissions can add up to unacceptable levels. Where an air­tight gypsum board assembly or air barrier is applied between the structure and the living space, these fumes will be fairly insignificant. If there is still concern, however, the TJIs can be sealed. BIN Primer Sealer is particularly good for this purpose because the white color allows you to visually inspect the job and make sure everything has been well coated. Another option is to use open-web roof trusses with dimensional lumber for the top and bottom chords and webs, thereby avoiding the use of pressboard entirely.

Special Procedures for Interior Garage Walls

Ideally, to prevent harmful automobile fumes from entering the home the garage should not share walls with it. If this is not possible, a series of extra procedures should be followed:

• Follow procedures for airtight gypsum board installation (as outlined in Divi­sion 9) between garage and home.

• Apply Type X gypboard to garage walls per code.

• Use a solid core, weatherstripped door between home and garage.

• Thoroughly seal the door sill with one of the sealants listed in Division 7.

• Make all electrical penetrations in the wall airtight. (See section on gasketed electrical boxes in Division 16.)

• Seal and tape any plumbing penetrations between garage and home with aluminum tape.

• Provide automatic mechanical exhaust ventilation in the garage as outlined in Division 15.

Sheathing

Subflooring

Interior-grade plywood and particleboard are typically used for subflooring in standard con­struction. Urea-formaldehyde glues are used to bond the wood during manufacturing. This is a concentrated, volatile form of formalde­hyde that contributes significantly to indoor air pollution. In addition, the subflooring may then be attached to the framing underneath with solvent-based glues that will also con­tribute to the pollution level.

Solid wood, as well as the cementitious subfloor sheeting more commonly used in commercial building, can be considerably more expensive, but exterior-grade plywood can substitute for interior-grade plywood for only a small increase in cost. While exterior – grade plywood contains less-volatile phenol – based formaldehyde glues, it will still release significant amounts of formaldehyde into the air when new. Airing out the wood by cross­stacking it onsite is better than installing it im­mediately after delivery. Sealing the wood af­ter it has been aired out will provide the most protection against toxic fumes and this extra step may be taken for chemically sensitive in­dividuals. We suggest the following specifica­tions for healthier subfloor installation: [8]

• structural cementitous sheeting

• їх finish floor boards laid parallel to walls over ix subfloor laid diagonally to walls may be a good solution when a finished wood floor is desired; verify for proper span conditions with the archi­tect or engineer

• exterior-grade plywood that has been aired out; may be sealed with BIN Pri­mer Sealer or another acceptable sealer on all six sides for extra protection for chemically sensitive individuals

Sill Plates

Sill plates or mudsills are decay – and insect – resistant wood members used in frame con­struction wherever wood comes into contact with concrete or soil. For many centuries be­fore toxic petrochemicals came to be used, builders had devised natural means for avoid­ing rot and insect infestation. They commonly charred the portions of wood that were to be placed in the ground or else used naturally re­sistant woods. From about 1974 to 2003, the standard building practice was to use lumber pressure treated with chromated copper ar­senate (CCA) or ammoniacal copper arsenate (АСА). CCA and АСА contain arsenic salts and chromium compounds that can leach out onsite and be absorbed through the skin or in­gested by mouth. They are extremely toxic to

both humans and the environment. The use of these chemicals for sill plates is now banned but they still will be found in most existing frame homes. CCA imparts a green tinge to the wood. You have probably seen this toxic wood used in childrens playground equipment.

It is important that no recycled sill plates containing CCA or АСА find their way into new construction, and you may wish to add the following to your specifications:. [7]

* ACQ Preserve: Wood treatment con­taining alkaline copper quaternary (ACQ)

* Nature Wood: A waterborne wood preservative containing ACQ

* TimberSIL: A nontoxic, arsenic-free wood treatment process that uses sodium silicate technology (SST)

• The heartwood of untreated farmed cedar or redwood is acceptable for use as sill plates where approved by local code officials.

* Where the sill plate is at least 18 inches above grade, a metal termite shield may be used instead of a treated sill plate if acceptable to local code officials.

Framing

Wall Framing

Where wood 2x wall framing is used, follow the guidelines for wood selection and storage in this Division.

Wood surfaces and edges exposed to the weather will usually be surface treated to make them more weather resistant. Wood that is not naturally rot resistant and that will come in contact with moisture must be treated for rot and mold resistance. Creosote and penta­chlorophenol are two commonly used wood preservatives that are quite toxic. Creosote is a dark-colored, oily tar that will outgas harmful vapors long after it has been applied.

Pentachlorophenol has been shown to cause liver damage in adults and fetal death and has been banned in some European countries. These substances should be prohibited for use in a healthy home. The wood treatment prod­ucts discussed below do not contain these harmful ingredients.

Wood Treatment to Prevent Insect and Mold Infestation

• BioShield: Wood preservative oils

• Bora-Care: Low toxicity, borate-based, penetrating preservative containing gly­col, used for protection against powder post beetles and subterranean termites

• Livos Donnos Wood Pitch Impregna­tion: Penetrating preservative for wood that is in contact with moisture

• PureColor: Two-stage stain formulation of pure mineral ions and oxygen catalyst for wood; no solvents, oils, VOCs, odors, acids, or bleaches; has antimicrobial and antifungal properties

• Shellguard and Armor-Guard: Borate- based wood preservatives for protection against wood-boring insects

• Timber Pro UV: Natural, plant-based, oil – based, waterborne breathable stain that seals and protects and is available in five standard and 40 custom colors with op­tional low-toxicity fungicide/algaecide (1 percent solution) providing mildew and algae resistance

• Timbor: Low toxicity, borate-based wood preservative that protects against drywood termites and wood decay fungi

• Weather-Bos’ The Boss: Four different formulas for protection of exterior wood surfaces

Wood Treatment to Provide Weather and UV Protection

Many wood treatment products for exte­rior use are solvent-based and highly volatile. They can continue to outgas for several days or even weeks. Although exterior applications will have far less impact on indoor air quality than products used inside the home, they will still affect the applicator and sensitive people who are in the vicinity. This problem can be completely avoided thanks to the wide range of more benign products now available. Some of these lower-impact products are:

• 9400 W Impregnant: Solvent-free, water – repellent, ultraviolet protective coating for interior/exterior wood; also effective in minimizing mold and mildew growth

• AFM Safecoat Durostain: Seven differ­ent earth pigment, semi-transparent wood stains for interior and exterior use

• BioShield: Wood preservative oils

• Hydrocote Polyshield: Interior and exte­rior polyurethane wood protection

• LifeTime Wood Treatment: Protects, stains, and beautifies wood products

• Livos Donnos Wood Pitch Impregna­tion: Penetrating preservative for wood in contact with moisture

• Livos Dubno Primer Oil: Undercoat for exterior wood

• OS Wood Protector: Preserves against water damage, mold, mildew, and fungus

• PureColor: Two-stage stain formulation of pure mineral ions and oxygen catalyst for wood; no solvents, oils, VOCs, odors, acids, or bleaches

• Timber Pro UV: Natural, plant-based, oil-based, waterborne breathable stain that seals and protects; available in five

standard and 40 custom colors with op­tional low-toxicity fungicide/algaecide (1 percent solution) providing mildew and algae resistance

• Weatherall UV Guard: Exterior acrylic wood finish that penetrates and seals, forming a protective shield against UV, rot, and decay; comes in clear and semi­transparent finishes

• Weather-Bos’ The Boss: Four different formulas for protection of exterior wood surfaces

• Weather Pro: A water-based, water-repel­lent wood stain

Wood Maintenance

Common products for stripping, cleaning, and brightening wood often contain harsh solvents. The following product is safer:

• Dekswood: Cleaner and brightener for ex­terior wood.

Wood Adhesives

Wood adhesives commonly contain harmful solvents. However, solvent-free solutions are readily available and may be specified. The fol­lowing adhesives are healthier choices for var­ious wood related applications.

• 100% pure silicone caulk: Can be used as a subfloor adhesive; specify aquarium-grade caulk without additives

• Chapco 244: Acrylic urethane latex wood floor adhesive

• DAP/Dow Corning: 100% silicone sealant

• DriTac 7500: Solvent-free, zero-VOC wood flooring adhesive

• Elmer’s Carpenter’s Glue: Low-о dor, nontoxic, water-based glue for porous materials

. GE Silicone II: 100% silicone sealant for a variety of indoor and outdoor applica­tions

• Roo Glue: Waterborne, environmentally safe adhesive for cabinetry, flooring, and most other construction materials

• Taylor Meta-Tec 2086 Tuff Lok-Link: GreenGuard certified solvent-free, low – odor polymer-based wood flooring adhe­sive

• Timberline 2051 Wood Flooring Ad­hesive: For laminated plank and parquet flooring

• Titebond Solvent Free Construction Ad­hesive: For plywood, paneling, and hard – board

• Titebond Solvent Free Subfloor Adhe­sive: For subfloors

Although Germany has been a leader in the Bau – Biologie and healthy housing movement, it was only two decades ago that the general public there became aware of multiple chemical sensitiv­ity disorder. This awareness followed the experi­ences of thousands of people who were exposed to lumber treated with both the preservative pentachlorophenol and the pesticide lindane. Hundreds of people developed chronic neurologi­cal complaints, chronic fatigue, and an unusually heightened sensitivity to chemicals that were pre­viously tolerated. Lindane has subsequently been banned in Germany as a wood treatment.

dipped in pesticides that are now banned in the US. In some cases, uncontaminated lum­ber can be picked up directly from a local mill, where the sawyer will be closer to the source of the lumber and will know whether pesti­cides are used where the wood was grown.

Wood Selection and Storage

Kiln-dried framing lumber is drier than air – dried lumber. It is therefore more true to size and less susceptible to shrinkage and mold infestation. Certified, sustainably harvested, kiln-dried framing lumber is now becoming widely available. Framing lumber of this type is currently slightly more expensive than stan­dard lumber, which is often logged using un­sustainable practices.

Wood may occasionally be delivered to the site containing mold. It can also become moldy while stacked onsite if it is unprotected. To avoid these problems, you should include the following instructions in your specifica­tions: [5] [6]

• Fir, spruce, and hemlock are preferred over pine where available at no additional cost to the owner.

• Wood stored onsite shall be protected from moisture damage by elevating it off the ground and covering it with a tarp during precipitation.

• Wood that becomes wet must be quickly dried by cross-stacking to promote aera­tion. It should have less than 16 percent moisture content, as tested by a moisture meter, and must be free of all signs of mold in order to be acceptable. (See Division 13 for moisture meter testing.)

Wood has historically been used as a compo­nent of a breathing wall system, whether it be the half-timber, wattle-and-daub construc­tions of medieval Europe or the log cabins of our ancestors in North America. (See Divi­sion 4 for an explanation of the breathing wall concept.) Wood is an advantageous material in a healthy home because it has the property of hygroscopicity. This means it has the ability to absorb and release moisture, thus helping to balance humidity levels and the electrocli­mate. However, for many chemically sensi­tive individuals the natural terpenes found in wood, especially soft or aromatic woods such as pine or cedar, are intolerable. Certain woods may need to be eliminated from, or sealed when used in, a home for a chemically sensi­tive person.

In standard home construction, the air space between the wood studs may be filled with insulation laden with chemicals. The exterior sheathing often contains formalde­hyde-based glue or asphalt backing. The gyp­sum board applied to the inside face of the studs may be finished with harmful joint com­pounds. If the home was built before 2004, the studs sit on a sill plate that is most likely pressure treated with a pesticide to prevent rot and insect infestation. When standard con­struction is the only option, we recommend that the most benign wall construction mate­rials available be used and that a barrier be in­stalled between the wall construction and the living space. Refer to Division 7 for air barrier product and installation information.

In some instances, creating a barrier for the purpose of blocking fumes can cause other problems when moisture from condensation becomes trapped inside the wall. Applying the gypsum board in an airtight manner will help block fumes but will not in itself block the nor­mal movement of water vapor. See Division 9 for more specific details on creating a barrier using gypsum board.

Construction lumber is at risk of con­tamination by pesticides when farmed, when milled, during transportation, and in stor­age. For those who have severe sensitivities to pesticides, it is important to locate a source for uncontaminated wood. Wood that is sustain­ably harvested can be traced from source to sawmill to distributor and its pesticide history can be determined. Certified producers and processors are encouraged to use least-toxic pest management. Some regional certification organizations have mandated a ban of pesti­cides for sustainably harvested wood in their jurisdictions. Certain imported woods maybe

CASE STUDY 6.1