If you are thinking of building or remodeling a house, you might want to know about health issues. Here are the main ones that can come up, and the methods the American Lung Association of Michigan and the builder S.R. Jacobson have used to handle them in Health House.
Often, Health House used the best solution. In a few cases, more measures are available, and they’re listed under “more options.” People with serious chemical sensitivities probably want to take these extra steps.
A common term to know here is “volatile organic compounds,” or VOCs. This is a round-up term for harmful gases emitted by solvents, paints and glues. It’s good to find low-VOC or zero-VOC materials.
Basement drainage
The problem: Damp foundation breeds mold, mildew and spores that aggravate allergies.
Health House solution: To keep water away from the basement, the foundation hole was dug large enough for a three-foot layer of sand under and around the cement foundation. Ground water drains away from the walls, rather than pressing in.
The house was sited at the high point of the lot so water drains away.
Before the foundation hole was refilled, a special mastic coating with a plastic wrap called Tutuf was applied around the basement’s exterior.
Radon gas
The problem: In a few houses, invisible, odorless radon gas leaks in from the ground and is caught in the lowest floor, where it’s a potential cause of lung cancer.
Health House solution: Below the basement floor and above the poured sand, the builders laid a plastic film to stop any possible radon gas from leaking in. Three inches of pea gravel was poured on top of that plastic.
As the foundation settled, extra care was taken to seal the inevitable gaps and cracks.
If radon shows up anyway, a system is built in to blow it off harmlessly. Two plastic pipes vent air from that gravel space below the basement to the roof. A nearby electrical hookup will let the home owner add an exhaust fan to the pipe.
Ductwork
The problem: If heating ducts trap water, they can breed mold and bacteria. If they’re filled with construction dust, they pour that tainted dirt into the air.
Health House solution: A duct-cleaning firm scoured and vacuumed all the ductwork.
Ventilation
The problem: A tightly sealed house traps indoor air pollutants. But a loosely sealed house, or a house with an exhaust fan, loses too much heat during winter.
Health House solution: This house is tightly sealed. But it can turn over fresh air quickly without losing heat because it has a good ventilating heat exchanger.
The ventilating heat exchanger will run constantly to bring in fresh air and exhaust old air. While doing so, it transfers warmth from the exhaust air to the new air coming in.
Subfloors and floor joists
The problem: Under the carpet, tile or wood floors, most new subfloors are interior-grade plywood. Beneath this, most new floor joists are a manufactured wood product. Both these contain urea-formaldehyde binders, a tough but highly toxic product that causes cancer in lab animals.
Health House solution: Subfloors are exterior plywood, assembled with a water-based glue. This has some formaldehyde, but much less than standard interior plywood.
More options: Don’t use plywood at all, but put 1-by-6-inch or 1-by-4-inch solid boards across the beams to make a subfloor. For floor joists, use only solid wood beams or metal beams.
Floor coverings
The problem: Vinyl flooring can give off harmful gases. Hardwood, ceramic tile and marble don’t. But the usual glues, grouts and sealers used with them do. Carpet is a complex issue.
Health House solution: Hardwood floors are used, but with special water-based and low-VOC glue, stain and sealers. Ceramic tile is used with a special low-VOC grout, and the grout was sealed to prevent mold.
More options: The stain and sealer used on the hardwood floors are low-VOC, because zero-VOC versions are not available. This should be fine for average people, but people with high chemical sensitivity might want to eliminate stain and use a beeswax finish, although it’s a lot of work.
Cabinets
The problem: Kitchen and bathroom cabinets are almost always made from pressed wood covered with wood veneer or laminate. But the glues in pressed wood are a serious carrier of urea-formaldehyde.
Health House solution: Kitchen cabinets are expensive solid cherry. Bathroom cabinets also are mostly solid wood, although both kitchen and bathroom do contain some plywood.
More options: For a more perfectly formaldehyde-free house, cabinets could be built entirely of solid wood. Another option is metal cabinets.
Countertops
The problem: Under their laminate surfaces, most countertops are made from slabs of pressed board, with its urea-formaldehyde binder, and they’re attached with formaldehyde glues.
Health House solution: All countertops in the house are the solid-state product, Gibraltar. Readers may be more familiar with this product under a competing brand name, Corian. Both give off no gases and clean easily, without the maintenance problems of grout around ceramic tile.
More options: Laminate tops could be OK, if applied over solid wood with a simple white carpenter’s glue.
Paint
The problem: Paints have long been a big VOC offender, especially oil-based paints. But the industry is rushing to find less harmful products.
Health House solution: A low-VOC latex paint by Sherwin-Williams, called ProMar 200, was used by all the interior designers.
More options: Some new paints have come close to zero VOCs. The Health House interior designers did not use these, though, because they’re made only in white. Once you add tints, the VOC level goes up.
For people who want a nearly zero-VOC paint, the most successful brand right now is Kurfees Coating, sold in some paint stores. Glidden and Benjamin Moore both came up with zero-VOC paints recently, although these first versions haven’t solved the technical problems as well as Kurfees.
Wallpaper
The problem: Vinyl wallpaper can carry a high amount of VOCs. So do some synthetic pastes.
Health House solution: Some designers used low-VOC paint as decoration-. Others used paper wall coverings, with a natural wheat paste.
Furniture
The problem: Furniture made from pressed wood-most cabinets, for example-carries a wallop of urea-formaldehyde binder. Overstuffed or fussy furniture can harbor dust and allergens.
Health House solution: All furniture frames had to be solid wood, metal or glass. Furniture also had to be fairly simple and easy to keep clean.
More options: People who are highly chemically sensitive may also need to eliminate foam padding and synthetic fabrics as well.
Window treatments
The problem: Excess fabric around a house can hold dust and allergens. Also, many fabrics are treated with sizing and finishing chemicals that aggravate allergies.
Health House solution: The interior designers did not want bare windows, so most used fabric, but sparingly. They were told to choose fabric that could be washed easily and often, to minimize curtains as dust-catchers.
More options: For people with serious allergy problems, the best window covers are vertical blinds, because they hold the least dust. Next are horizontal blinds. Fabric curtains should be washed before they’re installed, to eliminate the irritating finishes.
Combustion appliances
The problem: Appliances and furnaces that burn gas or any other fuel can create harmful combustion byproducts, such as soot, sulfur dioxide, nitrogen dioxide and, in extreme conditions, carbon monoxide.
Health House solution: A geothermal heating and cooling system, donated by Detroit Edison, draws thermal energy from the ground, heating the house with no flame or combustion.
The system is more expensive up front, but Edison says it will pay for itself in lower energy costs. Even though the house is a large 2,990 square feet, Edison predicts energy costs of about $70 a month.
More options: You can accomplish a similar goal with a gas furnace if you seal the combustion chamber completely and vent it to the outside, so no combustion air escapes into the house.
Other innovations
– Insulation: An new cellulose insulation called Nu-Wool, made from recycled newspapers, was blown into the wall cavities. This adheres to all surfaces, sealing voids at wires and pipes.
Because Nu-Wool is very dense, it achieves a high R-19 insulation level in the walls even with conventional 2-by-4 construction. Usually a builder would have to use 2-by-6 construction to fit in this much insulating power.
– Electronic air cleaner: A high-end Honeywell electronic air cleaner will capture 95 percent of dust particles, pollen, mold, spores, dust mites, smoke and outdoor air pollutants that bother people with allergies.
– Baking the house: To force out toxic gases that may still exist in any glued wood, carpet backing or finishing product, the heat is turned up high-about 85 degrees for four days, while the ventilator is kept running. This speeds up the outgassing of harmful products.
– Electrical outlets: Each electrical outlet is placed inside a Lessco brand outlet box to stop outside air and vapors from leaking at these points.
– Energy Seal: A crew from Nelson Energy Seal went through the house during insulation, applying toxin-free caulks and sealers to any spot of potential air leakage.
– Windows: A high-quality window by Hurd is built of wood, with special film on the glass and an inert gas sealed between the two panes.
– Central vacuum: This will decrease the dust in the air by removing particles without stirring up air as much as a conventional vacuum. The vacuum receptacle is in the garage so dust mites and allergens stay outside when the bag is changed.
– Blower door test: Jacobson can test the tightness of a house by sealing the doors and using a powerful fan to suck air out of the house. By using gauges to measure air pressure, he evaluates how air-tight the house is.
– Home automation: Honeywell’s TotalHome Automation System electronically controls lighting, temperature, appliances and security.
