Air quality in new homes

[eric_anderson]

The following is a report by the california research board about indoor air quality. Very scary stuff. To me the biggest take home message is to build with low voc and formaldehyde stuff as much as possible and use a HRV and run it all the time.

http://www.arb.ca.gov/research/apr/past/04-310.pdf

I did some trim work in a new house last year that gave me a headache every time I went in the house. The rooms with carpets were the worst.

I know dick is going to argue the HRV's waste electricity, but mine is on all the time and my total electiric bill is around 50$ @ an effective rate of 0.24$kwh
Cheers,
Eric

[Riversong]

All the report proves is that California builders are either oblivious of or don't care about the toxicity of the homes they build and the health of their occupants.

The "solution" is not to run high rates of ventilation, but to use non-toxic materials and methods.

I design my homes for only 0.25 ACH, which is more than enough to deal with humidity and CO2 control - as long as the house and its occupants are non-toxic.

[Dick Seibert]

For those who don't follow links here is the Abstract:

Abstract
Concerns have been raised regarding whether homeowners use windows, exhaust fans, and other mechanical ventilation devices enough to remove indoor air contaminants and excess moisture. In a multi‐season study of ventilation and indoor air quality of 108 new single‐family, detached homes in California, window use, ventilation rates, and air contaminant concentrations were measured. The median 24‐hour outdoor air exchange rate was 0.26 air changes per hour; 67 percent of the homes were below the California building code requirement of 0.35 air changes per hour; and 32 percent of the homes did not use their windows. Home‐to garage pressure testing guidelines were exceeded in 65 percent of the homes. The median indoor formaldehyde concentration was 36 micrograms per cubic meter (range of 4.8 to 136 micrograms per cubic meter). Nearly all homes had formaldehyde concentrations that exceeded guidelines for cancer and chronic irritation, while 59 percent exceeded guidelines for acute irritation. In conclusion, new single‐family detached homes in California are built relatively airtight, can have very low outdoor air exchange rates, and can often exceed exposure guidelines for air contaminants with indoor sources, such as formaldehyde and some other volatile organic compounds. Mechanical ventilation systems are needed to provide a dependable, continuous supply of outdoor air to new homes, and reductions of various indoor formaldehyde sources are also needed.

Robert, I agree, I never use sealants and engineered woods that contain toxic products and have never had the problem, I have used fiberglass insulation because code makes me use insulation, but apparently the toxic by-products of fiberglass are not enough to trigger the problems. We didn't have these problems until we had energy code requirements, and now green codes are vastly compounding the problems by making everyone use toxic products, in fact the word "green" has come to mean "toxic".

My IH has found that the state 0.35 is not nearly enough for homes with Green ordinances, and even raising the ACH to 1.0 is not enough, just like during the 80s "sick building syndrome" commercial building problem found that no amount of air exchange solved the problem.

Sealing buildings for energy efficiency together with green building requirements is proving to be a disaster, I agree, the solution is not more and more air exchange, the solution is removing all toxics from the building and allowing the building to breathe. At 0.35 ACH people are disconnecting their ventilation systems because of the additional costs of pumping and conditioning outside air, coupled with the allergic problems breathing constantly conditioned outside air.

[GaryJR]

Robert you mentioned to someone in another thread that they were suffocating their home that was breathing healthy for over 80 years.

Sealing up homes can be detrimental to the house itself and the occupants.

How would you determine what a house ACH is if the ACH was never taken into consideration when it was built? pressurize the house?

[Riversong]

How would you determine what a house ACH is if the ACH was never taken into consideration when it was built? pressurize the house?

The only way to get an accurate measurement is with a blower door test. But some old houses are going to be so leaky that they can't be pressurized to the standard 50 pascals.

Otherwise, you can inspect the house and make a guess. The natural air change rate depends on climate (colder zones create more exfiltration because of the difference in density of warm inside air vs cold outside air); wind exposure, velocity and fequency; occupancy patterns (how often are doors and windows opened or fans turned on?); as well as the construction type, quality and height (stack effect) of the house and whether it has a fireplace.

Very old, un-insulated homes can have 5ACH, while minimally insulated homes might have 3ACH. Any house built to today's codes and standards should have no more than 1ACH and tightly-built homes generally have less than 0.35ACH (which ASHRAE considers the minimum for a healthy IAQ).

The Air Tightness Zones in the attached map indicate that in cold areas (zone 1), it is not possible to meet ASHRAE 119 air tightness standards and ASHRAE 62 ventilation standards with natural ventilation alone (because of the tightness required in a cold climate).

[Dutchman]

[QUOTE=Dick Seibert;508141]For those who don't follow links here is the Abstract:

Robert, I agree, I never use sealants and engineered woods that contain toxic products and have never had the problem,

I try to do the same in my buildings but would love to know how you get around the use of LVL's for big easy spans (steel isn't always easy) and the Advantech we all use. I will usually make up my own beams with SPF and plywood to get around the engineered products, but sometimes you just need them.


[QUOTE=GaryJR;508152]Robert you mentioned to someone in another thread that they were suffocating their home that was breathing healthy for over 80 years.

Sealing up homes can be detrimental to the house itself and the occupants.

That was me, and yes, I agree, it is detrimental to the occupants. I wasn't trying to suffocate it, just trying to find the happy medium between enough properly installed defense systems against my Maine winters versus the use of natural gas for the heat I so desire. What I'm coming to for my own comfort is to have a relatively tight house and a super efficient heat system. If we keep trying top make things so tight that we don't require heat, we will kill ourselves with our creation....to save the environment by not using fossil fuels....to use too many products to keep out the cold...AHHH!

It seems (in many cases, not all) that the "science" of building construction (SIPS, foam, HRV, ERV, etc.) is forgetting about the siting of buildings on the landscape to make use of natural resources (solar, landforms for protection, drainage, etc.) to the point where we have forgotten the fundamentals of proper design.

[Riversong]

I try to do the same in my buildings but would love to know how you get around the use of LVL's for big easy spans...sometimes you just need them...we have forgotten the fundamentals of proper design.

I agree with your last statement. With a return to the fudamentals of design, we don't "need" big easy spans. When I begin designing floor plans, I always include a center bearing wall on each level. Large headered or flush-beam openings in those walls are possible with reasonable spans (up to 8').

There are some elements of contemporary design which simply don't make sense or are completely unnecessary. A house is for shelter - if we try to make it an art gallery or an expression of someone's ego, there will be costs (and not just financial).

[GaryJR]

Thanks for that informative reply Robert. The blower door test was what I was referring too when I said Pressurize the house.

"There are some elements of contemporary design which simply don't make sense or are completely unnecessary."

Along with most everything else in our rat race lives, but that's where we are in our society. Practicality, efficiency and functionality now takes second stage to aesthetics.

[Riversong]

Along with most everything else in our rat race lives, but that's where we are in our society. Practicality, efficiency and functionality now takes second stage to aesthetics.

Only in so far as we go along with it.

[NW Architect]

Notice, please, that the homes studied were NEW homes, which I take to mean very recently constructed. To wit, still young enough to have that "new home smell".

The lesson I take away (besides "use less toxic stuff", and "seal away the toxic stuff stored in the garage") is that new construction needs to be flushed out with air for awhile before one moves in and starts to operate the structure "normally".

I don't know that it informs me of anything regarding been-built-for-over-6-months-ago construction

[Dick Seibert]

NW, would you believe that because of the Chinese sheetrock problem that there is now a formaldehyde association defending formaldehyde in our homes?

However, the CPSC had to defend its study after a chemical trade group criticized one of its findings related to the presence of formaldehyde.

The Arlington, Va.-based Formaldehyde Council took exception to that finding and issued a statement.

The Formaldehyde Council, a group of chemical producers and manufacturing firms, lists its mission on its Web site as being “[t]o encourage accurate scientific evaluation of formaldehyde and formaldehyde-based materials and to communicate sound scientific information relating to the uses, benefits and sustainability of these products.”

Betsy Natz, executive director of the council, cited her group’s objections.

"Formaldehyde is not associated with corrosion and is not a component of dry wall. It is irresponsible to speculate that formaldehyde and hydrogen sulfide can act in a synergistic or additive manner to cause irritant effects in human beings at the low levels found in the CPSC study,” she said.¹

Much is made of the alcohol and tobacco industries, I'd say the drug and chemical industries are worse.


¹ http://www.property-casualty.com/Iss...Corrosion.aspx

[Riversong]

Much is made of the alcohol and tobacco industries, I'd say the drug and chemical industries are worse.

But none can compare with the "financial services" industry (aka Banksters). They don't have to advertise. Customers come to them begging to invest their hard-earned money. The banksters then lend money they don't have to people who can't pay it back, or invest in fictions called derivatives or gamble it on credit default swaps and lose it all, get re-imbursed from taxpayer coffers and give themselves multi-million dollar bonuses for their efforts.

[Dick Seibert]

Notice, please, that the homes studied were NEW homes, which I take to mean very recently constructed. To wit, still young enough to have that "new home smell".

It apparently goes up after occupancy:

The homes I studied were unoccupied and had minimal furniture. Formaldehyde levels will likely increase when the homes are occupied, as cooking, smoking, and furniture can increase formaldehyde in a home.

Los Altos requires new homes to be GreenPoint Rated and many Bay Area cities are following Los Altos's lead. Southern California cities are adopting the analogous Green Builder certification. To meet the energy conservation requirements of these programs, these new homes allow minimal fresh air to leak in. GreenPoint Rated also encourages use of manufactured wood products to reduce consumption of virgin timber. Plywood, particleboard, and medium density fiberboard (MDF) conserve resources, which is good, but they are often manufactured with resins that emit formaldehyde for decades.

"Sick Building" Syndrome Redux
The energy crisis of the 1970s brought remarkable advances in energy conservation in commercial buildings, but ventilation in some buildings was reduced to levels where chemicals concentrated in indoor air. "Sick buildings" of the early 1980s were a result, in part, of inadequate ventilation. History is repeating itself, as homes are built with energy saving in mind.

We can fix this. Codes now require office buildings to exchange the air once per hour; homes could do this, too. Wood products can be made with soy-based resins, which do not emit formaldehyde. The US Green Building Council may require formaldehyde testing in their 2012 revision of LEED. Build It Green could require homes to meet the K8 formaldehyde standard or cities could require it even if Build It Green does not. Citizens can demand that new homes be tested for indoor air quality before purchasing them.

Unfortunately, GreenPoint Rated does not balance conservation with indoor air quality. The problem is that it requires energy conservation measures, while recommending indoor air quality measures. I have found that many Green- Point Rated homes built under the current criteria have high formaldehyde levels. Item K8 on the GreenPoint Rated worksheet specifies formaldehyde concentration below 27 parts per billion (ppb), but that item is optional. Since it is very easy to receive adequate points for indoor air quality, builders have no incentive to address this problem¹

BTW, this IH works with Bud Offermann's study for the California Air Resources Board and participated in the testing for the article. She just told me:

Offermann and I are both presenting our data next May at the AIHA conference in Denver

¹ http://lomaprieta.sierraclub.org/The...p?q=2010010201

[eric_anderson]

The houses studied and monitored were between 6 months and 5 years old. NW how long are you proposing to let them air out? I think you would have a hard time convincing someone paying a morgage to wait 2 years for the bad stuff to exit the house.

cheers
eric

[icare_dou]

All the report proves is that California builders are either oblivious of or don't care about the toxicity of the homes they build and the health of their occupants.

The "solution" is not to run high rates of ventilation, but to use non-toxic materials and methods.

I design my homes for only 0.25 ACH, which is more than enough to deal with humidity and CO2 control - as long as the house and its occupants are non-toxic.

The problem appears to be nationwide. Just look at the extensive data recently released in the drywall study. The formaldehyde in those homes ranged from 79 to 400 ppb which is about 100 to 500 micro grams / cubic meter.

Even if a home could be build with zero emmissions, there is still the stuff that we bring into the home. This could be furniture, clothing, cleaning supplies, personal care products etc. Not to mention air that comes in from the garage.

Commercial buildings require 1.0 ACH, why do we think homes need less?