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Gas cooking

Gas cooktop with words Gas cooking and indoor air pollution - orangeGas cooking is highly in demand, sought after for the quick response time and precision with heating and cooling. The vast majority of our clients have a strong preference for gas cooking over either induction or regular electric cooking.

In recent years, studies have shown that gas stoves can be a significant source of indoor air pollution. When in use, the hood should always be in use to foster healthy ventilation. That part alone is often forgotten, but it turns out that gas ovens and cooktops may be polluting even when no one is cooking.

Health hazards of gas cooking

Last week, the New York Times published the findings of a Stanford Doerr School of Sustainability and PSE Healthy Energy, a non-profit), study which found that in the 87 homes with gas stoves tested in Colorado and California, benzene was detected in every home, both in the kitchen and beyond, after just 45 minutes of using either the oven at 350 degrees or a single stove burner.

Benzene is a cancer causing agent and no safe levels of exposure to it are known. It is worth saying again: benzene was produced by gas cooking in every tested case.

In about a third of the tested homes, the benzene level exceeded what would be found with second hand smoke. The study also suggests that the smaller the home, the worse the results.

And it lingered for hours.

You can find the New York Times article on it here. You can see the results on this site, too: Environmental Health News.

This isn’t the only place we can find warnings about gas cooking and air pollution. From the State of California, Indoor air pollution from cooking:

  • “Natural gas stoves can release carbon monoxide, formaldehyde and other harmful pollutants into the air, which can be toxic to people and pets.”
  • “If you have a gas stove, a qualified technician should inspect it every year for gas leaks and carbon monoxide.”

It’s not just gas cooking that produces indoor air pollution

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Where are the high voltage power lines?

High Voltage Power Lines Collage

High Voltage Power Lines from around the West Valley.

High voltage power lines are a “location issue” that impacts real estate values, and it sometimes elicits worry regarding safety.

High voltage power lines: how far is far enough?

Something we have spoken about recently with our clients is being far enough away so that if the tower and high voltage power lines were to fall, they’d miss your home and property. In our recent series of atmospheric rivers in January 2023, in San Jose one of these large transmission towers did fall down. It’s rare, but not impossible.

I have not seen a website that can tell us how tall any given tower is, but from what I have read online, it seems that most of them are under 200 feet tall, but some could be higher than that. In most cases, that puts the lines about 4 houses away if the lots are a typical 6,000 SF lot of 60′ across the front and 100′ deep.

We cannot speak to the concerns around potential increased risk of cancer or other problems. Each consumer should research that issue on his or her own.

Where are the high voltage power lines?

High Voltage Power lines - map - CaliforniaYears ago, I painstakingly mapped out the transmission lines from what I knew on the ground and what I could tell from tracing the Google satellite view. (You can find that link near the bottom of this article.)

Today, though, there’s something better than my map available online. The California Energy Commission has a map of the transmission lines that you can view using THIS LINK. Or click on the image at the left.

From the landing page you can zoom in or out. It covers the entire state of California – you might find it interesting to navigate around a little.

Also, a few years ago, PG&E published an interactive map where you can view the location of electric lines (I’ve filtered the imbedded map below to show Electric Transmission Lines in the South Bay), and another map of natural gas pipelines, searchable by address. This doesn’t cover the entire state, but it does cover all of the Bay Area / Silicon Valley.

The PG&E map:

On the map I hand-drew at the bottom of this article I did also include the location of schools. Quite a lot of schools do have transmission lines present.

What other location issues are there to factor in?
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Dam Failure

When buying or selling a home in California, consumers can learn if the property is in a zone marked for potential flooding due to dam failure. The disclosure companies will not say which dam is causing the risk, or if it’s several since often there will be more than one dam along the same creek or river, as is the case along the Los Gatos Creek.

Quick take: you can learn about the areas which may be impacted by flooding due to dam failure at this link: Dam Breach Inundation Map Web Publisher.

Dam failure versus flood plain

To clarify, the 100 year flood plains and 500 year flood plains are different from the flooding due to a breach in a dam or levee.  If someone buys a financed home in a 100 year flood plain, the lender will require flood insurance.

Also relevant to the requirement for flood insurance: the 100 and 500 year flood plain inundation risks are considered to be “natural hazards” and the flooding from dam breaches are not, since humans have created the dams (or levees).  Per FEMA: “a flood resulting from changes in river flows is a natural hazard, whereas flooding due to a dam failure is considered a manmade hazard, and therefore excluded from the National Risk Index.”

Approximately 25% of floods in the U.S. are outside of the flood plains. It may be advisable for those in other areas to consider buying flood insurance even if it is not required by the lender.

Map of flood risk from dam failure

Recently Clair sleuthed out the State of California’s Dam Breach Inundation Map Web Publisher. This interesting and helpful tool is an interactive map covering both most counties and most dams. I encourage our readers to check it out.

 

Dam failure flood zones in Santa Clara County

Click on the image to view the live Dam Breach Inundation Map to better understand the risk of dam failure

This Dam Breach website indicates which dams have their flood risk from failure marked in one of four colors to indicate the higher or lower risk levels. In Santa Clara County there are more than a dozen dams marked at the highest risk category, and some of them hold a large capacity of water. (Some of the dams appear to not be at lake-like reservoirs, but more like covered percolation ponds or holding tanks.)

The concern today, of course, is what happens if we experience a large earthquake and any of these dams fail.

Lake Anderson in South County is the largest reservoir in Santa Clara County. It is undergoing a 10 year seismic retrofit and until it’s completed is at only 3% capacity for safety reasons.  You can view a short video about the retrofit here. With that in mind, take a look at the image below, which showcases what areas could be inundated should the dam there fail.

Dam failure flood zone with failure of main dam at Lake Anderson

Click to view the live map

The map doesn’t show if the flooding goes beyond the county line to the south, and unfortunately not every county appears to be participating in this website and not every reservoir is covered. I was curious about the enormous San Luis Reservoir just beyond our county’s border, but there was no map for that one.

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Location research

Real estate location research onlineInterested in a home or area? Location research is something you can do upfront, before seeing a home or neighborhood. Researching the commute time, crime, hazards, convenience, and more before visiting a property before seeing it can prevent wasting a lot of time.

Realtors can provide valuable insight into homes, areas, disclosure package red flags, and more. There are many things that consumers can check on their own, though. I thought it would be helpful to provide some online resources to help. This is not an exhaustive list – think of it as a starting point.

Some location research information will be included in the seller’s pre-sale disclosure package via the Natural & Environmental Disclosure Reports. Normally in Silicon Valley those disclosures are available upfront, before buyers submit offers on a house or condo. If you have that NHD report, you may not need to use the links I’m sharing below. Not everything is disclosed, though. In some cases, buyers are given links to do their own research. That’s the case with the Megan’s Law Database, for instance.

Links to start your location research

Below are the promised links. I’d welcome your feedback!  (more…)

Is Your Refrigerator Flooding?

Refrigerator with water dispenserRefrigerator floods are no laughing matter! Last month, my sister in-law’s fridge leaked causing the hardwood floors to pucker and swell, pushing cabinets and even lifting countertops! They’ve had to move out while their kitchen undergoes a massive overhaul. When my refrigerator line broke back in 2012, it was a similar story. The damage was extensive, and repairs were time consuming and expensive! So what can cause leaks and flooding and how can homeowners prevent it?

Causes for Refrigerator Floods and Leaks

Does your refrigerator have an automatic icemaker or a cold-water dispenser? If so, that plumbing is all capable of breaking. What if you don’t have a water line to your fridge? You can still have a leak. Humidity from the air and produce becomes ice or water when cooled. Modern refrigerators have been designed to automatically defrost: ice is melted, flows down a drain, and collects in a drip pan where it is heated (usually via waste heat from the refrigeration system) to evaporate the moisture. If the condensate is not taken care of properly it can become water damage!

Looking a little more closely, here are a few common causes:

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NEW California Disclosure – Home Fire Hardening Disclosure and Advisory

Fire Hardening and Defensible Space Advisory Disclosure and AddendumJust about every year California amends what sellers are required to disclose, and one change that I think we’ll be seeing a lot of is about home fire hardening. Many agents, including myself, will begin to use the fire hardening disclosure / document (which has already changed once in six months). The current one, as of June 2021, is the C.A.R. Form FHDS, 5/21 Fire Hardening and Defensible Space Advisory, Disclosure, and Addendum.

So what is in this document, who will have to use it, and how can it help buyers and current home owners?

The CAR Fire Hardening and Defensible Space form is a two page document completed by the seller of a residential non-commercial property to notify the buyer of fire hazard zoning, code compliance, and possible vulnerabilities and/or defensible features. Both the buyer(s) and seller(s) sign to acknowledge receipt and consent to comply with the appropriate terms in paragraph 4B.

Who Will Use This Form? Paragraphs 1 and 2: Prerequisites

This disclosure is required for homes (1-4 unit residential properties) in high or very high fire hazard severity zones when the seller must complete a Transfer Disclosure Statement (TDS form). Sellers for California real estate transactions falling within those criteria are obligated to provide specific information contained in this form to the buyer. If these properties were improved or were built before January 1, 2010 there are additional stipulations. However, use is not restricted to properties in these zones.

Owners of residences where the zone is unknown, or those outside of the designated fire hazard zones which are “in, upon, or adjoining a mountainous area, forest-covered land, brush-covered land, grass-covered land, or land that is covered with flammable material,” (Gov’t Code 51182 and 1C in CAR FHDS 5/21 – basically, homes in or near ample kindling) should also make these disclosures if they might be considered materially important. Even when it’s not legally necessary, any homeowner might voluntarily disclose using sections of this form. To show that a home is not in a designated high or very high fire hazard severity zone, sellers simply check the box indicating so in paragraph 2B.

Is the address in a high or very high fire hazard severity zone?

Not all homeowners know if their property is in one of these zones, but it’s the seller’s responsibility to find out! In paragraph 1B the form suggests that a natural hazard zone disclosure company could determine this information (and if you’re selling you may have already ordered a report that would contain those details), but it certainly isn’t the only resource.

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Asbestos in homes

Most of Silicon Valley has pre-1978 homes,  and most of them contain some amount of asbestos, commonly on the HVAC ducts and, more visibly, in some popcorn or acoustic ceilings. It can also be in less known areas, such as vinyl flooring or perhaps the glue under the flooring.  Homes built after 1978 are far less likely to be effected. Asbestos can be found in almost any product, especially in older parts of the home where fire retardancy would be beneficial.

Very few people test their for asbestos in homes. Seeing that a seller has “no reports” on items like asbestos or lead on their home is not uncommon, but it does not mean it is not there, particularly in older properties.

Undisturbed asbestos is not supposed to pose a health risk. I know for a fact that my 1977 built home has asbestos on the boots, where the ducts come up to the heat register. Since it is on the external part of the ducting, not the inside, the air in our house should be clean and free from asbestos.

What is it?

Like mold, asbestos is a naturally occurring substance found in some soils, and sometimes mined. (Click on the image below to see a map of sites in California in which there is or is suspected to have asbestos present.) In the San Jose area, it’s known that asbestos was found or mined at the New Almaden Mine and also in the area near Communications Hill where KB Homes built a large subdivision.

Santa Clara County - naturally occuring asbestos

Asbestos is the common name for a group of silicate minerals made of thin, strong fibers, best known for their use as excellent fire retardants. Not many realize that it occurs naturally in certain areas, including California. The most common naturally occurring Asbestos is Chrysotile, often found in serpentine, common to the Sierra foothills and the Coast Ranges.

What does that mean? Since Asbestos are minerals, that means they are generally stable and will not evaporate. However, the mineral can be crushed into a fine dust which will float in air – this is referred to as friable asbestos. Friable asbestos, suspended in air and breathed by humans is a carcinogen linked to the development of lung cancer.

What are the risks of asbestos in homes?

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The Healthy House

Air quality monitor - one way to know if you have a healthy houseIt’s the end of the year and many people are making New Years Resolutions or New Years Goals.  Instead of directly focusing on your own health, how about looking into making a more healthy house? Indoor air quality contributes to the health of residents just as much as that extra serving of vegetables or extra thousand steps per day.

When the summer and autumn fires are raging in California, we are all keenly aware of pollutants. We check PurpleAir.com and replace our filthy air filters faster than usual. Some of us even found ourselves buying air quality monitors for the first time, all in hopes of having a healthy house.  When the fires get put out, we may not think much about having a healthy home until another “Spare the Air” day is called.

Healthy House Challenges

This last summer, we were one of many families purchasing an air quality monitor (seen in photo, it was around $120 online).  We were surprised at the amount of indoor air pollution caused by frying foods.  That was info we tripped into – the monitor was on because of the smoky skies, but it was the friend chicken that sent the PM2.5 score soaring into the 400s. And it took hours for it to come back down to normal (in large part certainly because we could not open our doors and windows to air it out). That was a lesson!

One of the least known but perhaps one of the biggest risks involves gas cooking, as well as the use of other gas appliances, in the home. What many cooking aficionados do not realize is that every single time you cook with gas, you also should be using the vent to clear the gas fumes lest you contribute to a buildup of carbon monoxide (and other pollutants) indoors.  (Venting is also crucial with other gas appliances such as the furnace and water heater.)

Carbon monoxide detectors are now mandatory in California homes if there are gas appliances, not just at the point of resale but in all houses, condos, town homes etc. – but even the best devices can fail or have the batteries die, so best to avoid relying on them alone and make sure to use care in venting all gas devices whenever in use.  There are some studies indicating that gas cooking and the use of other gas appliances indoors may aggravate respiratory conditions such as asthma and increase pulmonary (lung) risk, too. Carbon monoxide is the best known, but not only pollutant, that may come with gas appliances.

Along the same lines, home inspectors suggest that fireplaces with gas logs or jets never fully close, but instead have a small block to keep the damper from sealing completely. This is also so that the carbon monoxide can vent out.

Radon is thought to be a non-issue in California, but Silicon Valley is generally a moderate radon area. Care should be taken particularly in properties with basements and in homes where occupants smoke indoors.

Other issues include mold and dust, which are especially hard on people with allergies or lung disease, but can also irritate eyes. For structures built prior to about 1978, lead may be present too.

When buying or selling residential property in California, the Residential Environmental Hazards booklet is provided.  It can be found online via a variety of sources, including the State of California’s website.  If you haven’t seen or read this booklet recently, I would like to suggest that you have a look and consider incorporating some of the suggestions and tips in the coming year to make your own home a healthier one:

http://www.cdph.ca.gov/programs/CLPPB/Documents/ResEnviroHaz2005.pdf

A last point about this fabulous booklet: do not read right before going to bed!! 

Additional information from the World Health Organization can be found here:

WHO Guidelines for Indoor Air Quality: Selected Pollutants (book, 2010)

Here’s to a happy and healthy 2021!

 

 

 

Who needs a carbon monoxide detector, and where should it go?

First Alert carbon monoxide detectorFor several years now in California, having a carbon monoxide detector has been required in virtually all homes in The Golden State. This is not a point of sale requirement. It is a requirement for all residential dwellings which burn gas in any capacity (stove, furnace, etc.), or have a fireplace, or an attached garage as a matter of public safety.  They are exempt in all electric homes that do not have an attached garage or fireplace.

Where are the carbon monoxide detectors to be placed? The carbon monoxide detectors should be on every level of the home, including the basement.  If you live in a multi story home with the garage at the bottom, you do need one at that level also (just inside the door, once you are in the habitable area) as well as on the main floor, bedroom floor, and any other level you may have. In a single story home, just one carbon monoxide detector is sufficient.

Additionally, carbon monoxide detectors need to be in the bedroom area of the home. If a bedroom has a gas fireplace or wood burning stove (or any other fossel fuel source of heat), there must be a CO detector in the room. Otherwise, in the hall is fine. If bedrooms are not all in one part of the home, there needs to be a detector near each bedroom.

The cost of the device ranges considerably – from less than $10 each to more than $200 each. Some are plug in, some battery only, some feature LCD displays. Some are combination smoke detector & carbon monoxide detectors. Nest makes a CO alert, too.  We put a First Alert detector in our house, and the cost was around $20 – $30, but there are many brands from which to choose. (You can also buy portable CO detectors.)

Once installed, it should be checked periodically (along with your smoke detectors) to make sure that it is functioning properly.

Remodeling your home? When you apply for permits, be aware that the city or county inspector who visits your property will be looking for smoke and carbon monoxide detectors. If you don’t have them where needed, your remodel will not pass inspection. Your inspector will need to return, and normally that results in an extra cost to you.

Carbon monoxide poisoning can be very dangerous, to the point of death. If you don’t have a detector, go get one immediately.

Read more:

From the CalFire site (pdf):
http://osfm.fire.ca.gov/strucfireengineer/pdf/bml/frequently%20asked%20questions%20on%20carbon%20monoxide.pdf

From the City of San Jose: http://www.sanjoseca.gov/index.aspx?NID=5344

Is there a radon risk in Silicon Valley homes?

 

 

 

Residential Wood Burning: What You Can and Cannot Do

Fireplace with Lone Hill Quarry Stone.pngMore likely than not, you either own or have shopped for Silicon Valley homes with fireplaces. In that case, you’ve likely also heard tale about the new law that would force homeowners to replace older fireplaces with new gas only ones or decommission them entirely before selling. Let me quash those rumors now – homeowners with wood-burning fireplaces do not automatically need to replace them at the sale of the property at this time. But what’s behind the rumor anyway?

History

About a year ago, there were proposed regulations in place that were going to make stipulations for home sellers with older fireplace in the San Francisco Bay Area, including San Jose, Los Gatos, and nearby. Amendments have since been made to the ordinance, removing this requirement. These were part of Regulation 6, Rule 3: Wood-Burning Devices, which was adopted in July 2008 to regulate and improve air pollution levels for the health of the Bay Area community (Wood Burning Regulation). Its immediate effect was to enforce Winter Spare the Air Alerts and Mandatory Burn Bans. The regulation also stated numerous rules that would be effective at future dates (mostly beginning November 1, 2015/6), including many that will be passed this year and in the future, up to 2020. So, while you don’t need to worry about replacing your fireplace before you sell, there’s plenty to be aware of when you use, replace, repair, and install your fireplace – and you may still need to replace it.

Pollution

Smokey sky from fire June 2008With 1.4 million woodstoves and fireplaces around the Bay Area, it’s no surprise they make up a major part in the region’s air pollution – approximately one third of winter pollution! That’s greater than the amount of pollution caused by vehicles. Burning solid fuels produces what is known as soot, or more scientifically, PM2.5, which stands for Particulate Matter with diameter of 2.5 microns or less (Ordinance). These particles in the air are a form of pollution which is so fine that when breathed in it can penetrate deep into the lungs and even enter the blood stream. Wood smoke contains a group of compounds that are similar to second-hand cigarette smoke and are likewise hazardous (2012 flier). Studies show that this type of pollution can cause a variety of health conditions which can put undue stress on individuals with weak respiratory or cardiovascular systems. Apparently 1 in 7 Bay Area residents has a respiratory condition, and these folks of course are more vulnerable to problems from pollution. Immediate effects might be watery eyes and coughing, while long-term exposure to polluted air can permanently harm lung function, capacity, and development – possibly instigating diseases like asthma and bronchitis. “Eliminating residential wood burning during a Winter Spare the Air Alert can reduce soot in the Bay Area by 35 tons each day” (Wood Burning Regulations Flier). On top of the particulate pollution, wood smoke also contains a variety of gases, including toxins like dioxin (Wood Burning Regulations Flier).

But why winter? What about summer barbeques? Weather is important in regard to the displacement of these polluters. Spare the Air Alerts are hardly ever called when it’s been raining. Cold, still weather conditions cause the smoky air to become trapped near the ground, allowing pollution to build up to unsafe levels (Flier). When a Spare the Air alert is not called but data indicates worsening conditions there may be an optional compliance health advisory in the form of a Recommended No-Burn Day. And as for summer barbeques – the weather conditions in summer are more prone to heightening levels of ozone than soot, so Summer Spare the Air Alerts are placed based on very different weather and pollution concerns.

Other than pollution, there are still plenty of reasons to not burn. Fires are not a very efficient form of heating, and many fireplaces actually rob your home of heat, sending hot air up the chimney and out of your home. Prevent heat loss (and the need to burn more fuel or crank the thermostat) by keeping your home well insulated and weatherized. Get more efficient heating with an EPA certified device or alternative natural gas or electric heater. (more…)