Homeowners are increasingly interested in building materials that are energy-efficient and reduce heating costs over the long-term. All sorts of things are going green nowadays – from renewable resource-based bamboo wood floors to low-flow toilets and smart heating systems, it’s easy to increase your home’s efficiency and save money as well as the environment. There are many ways in which you can modify your house for this purpose, and Low-E windows are an extremely popular type of replacement for standard glass panes. How do these work?

The “E” in Low-E windows stands for “Emissivity.” Emissivity refers to the ability of a material to absorb incoming energy and emit it via radiation. All materials will either absorb and emit or directly reflect energy. A mirror, for instance, reflects most light energy and only absorbs a little, giving a shiny reflective surface we can look into. Concrete, on the other hand, will absorb most of the thermal energy that hits it, and emit it as heat; this is why it will feel warm to the touch on a summer day.

Sunlight contains a mixture of visible light, ultraviolet rays, and infrared light in the form of heat; window glass is naturally highly emissive, and it lets all three of these wavelengths through into your home. While it’s great to let visible light into your home, the other two are not as helpful; they will interact with surfaces in your home like fabric, wood, tile, and furniture, many of which will absorb and emit the rays. Ultraviolet light causes fabrics to fade and skin to burn; infrared heat will be emitted by your surfaces and increase the heat in your house – like when the sun-drenched tile floor of your kitchen becomes painfully hot to walk on in bare feet.

Low-E windows are coated with a metal that reflects UV and infrared light, while still allowing visible light to pass through. There are two types of Low-e glass: hard coat and soft coat. This refers to the type of material used in coating the glass. In hard coat, a layer of tin is applied directly to the molten glass during production, and it is very tough to scratch it off. Soft coat windows are coated with silver or zinc, applied in a vacuum and sandwiched between another pane of glass to protect the coating. It is also sometimes infused with argon gas to prevent the metals from oxidizing if exposed to air.

While Low-E windows may cost more, they are effective in reducing energy costs for your home; by reflecting ultraviolet and infrared rays away, they prevent overheating in the summer (reducing air conditioning use) and they also help the house retain its heat in the winter by preventing it from escaping through the windows. It’s estimated that they can filter out 40-70% of the heat normally transmitted through window glass, and reduce energy loss by about 40%. However, there are some strange disadvantages to Low-E windows, which we’ll discuss next week.

A purchased home is more than just four walls and a roof over your head; it’s an important investment in your future. Of course, the nature of home ownership has changed drastically over the past few years thanks to the economic crash in the late 2000s; there was a time not long ago when a house was an investment that was almost always guaranteed to pay off with a profit for the owner, and this is no longer the case. Nowadays, homes are becoming a different kind of investment, and balancing personal comfort over potential future value can be a delicate and frustrating balancing act. Some of your favorite features can seem like sore thumbs to others; others may be huge selling points. While you can’t do much about subjective tastes, you can be aware of the factors that add or subtract value from your home, even if you’re not looking to sell just yet. Here are a few very basic principles of house value to keep in mind.

Keeping it General
After a few years of living in your house, it can be difficult to see it through a stranger’s eyes; every nook and cranny contains a lovely memory or unique treasure that makes the home your own. However, a home’s layout should perform a delicate balancing act to appeal to potential future buyers. Ideally, it should strike the right balance between specialization and generalization, and between memorable and neutral. We’ve discussed in previous blog posts how important it can be to have updated kitchens and bathrooms, because these rooms get such heavy use every day; even small updates to the lighting and fixtures can make a world of difference.

However, it’s not just about having beautiful commodes and countertops; the rest of your house is important too. One surefire way to devalue your home is to decorate it with an incredibly specific theme or concept. While you may absolutely love the tropical basement tiki bar, or the nautical-themed wallpaper in your child’s bedroom, a future seller may recoil. Very design-specific features or renovations may seem like a key selling point, but may paradoxically devalue your home instead. For instance, an ultra-modern kitchen with extremely high-maintenance appliances might seem like a winner; however, it may actually turn off potential buyers who don’t want to read a manual in order to learn how to turn on the stove. If you’re planning to sell your home in just a few years, resist the urge to go wild with the taste-specific decorations and go for something a little more neutral instead, which will appeal to more potential buyers.

Standing Out From the Crowd
There are also some ways that you can make your house unique and appealing. A simple well-designed floor plan is more desirable than a cramped space with lots of smaller rooms; removing a few walls and opening up the space makes the entire house feel larger. Some specialized rooms can be extremely valuable, such as a well-organized home office/guest room; many people work remotely nowadays, and a separate space can be a huge bonus. A dry, finished basement is also a fantastic selling point; more and more homeowners are exploring the potential uses for their basements, and a cleanly finished space is far more appealing than bare concrete floors and dingy lighting.

Speaking of lighting, there’s one way to brighten your home and your future: lots of light! Skylights, large windows, and bright rooms feel large and cheerful, and contribute to your home’s value. It’s worth adding a skylight to a small interior bathroom. Try a solar tube system, which uses mirrors and solar panels to direct sunlight into a ceiling lens in any room, without having to cut through your roof for a skylight. With a few touches, your home will increase its future value—and contribute to your current enjoyment of it right now.

Home renovation has increased in the past few years, with more homeowners choosing to upgrade their existing property than try their luck in the realty market. With the economy still on shaky ground, a great deal of these renovations will be done with an eye on keeping costs as low as possible; the remodeling market and home improvement industry is focusing on projects with fewer luxury splurges and more money-saving tactics. But budgeting isn’t solely about reducing costs or buying cheap; it’s also about being able to discern value and make good costly decisions. Sometimes it’s actually better to spend more money right now, because in the long term you will save more overall. Here are a few more tips for when the long-term benefits will outweigh the short-term costs in a renovation.

Consider the LBD
Any woman will tell you that the little black dress, or LBD, is a wardrobe staple for one very good reason: it never goes out of style. Fads come and go, and hot fashions burst forth and then recede like ocean waves. The chalkboard paint indie chic of today’s kitchens may be embarrassingly outdated in ten (or even five) years, just as we roll our eyes and groan at the tacky avocado and mustard appliances of 1970′s kitchens. If you’re doing a major renovation of a kitchen or a bathroom, it’s best to go with a timeless style that won’t get tacky by the time you’re ready to sell your house. These two rooms are particularly prone to this trend, as they generally get the most wear and tear and have several appliances and fixtures that must be bought. While you may be renovating for your family rather than for profit, it’s still prudent to take your future property value into account when designing your renovation.

Avoid the One-Time Splurge
Renovating on a budget means making sacrifices, and it can be tough to downgrade your dream kitchen to the reality of what’s in your wallet. As you compromise on item after item, it’s easy to start coveting just one aspect of your “If I Had A Million Dollars” dream plan — and there may even be money in the budget for one such piece. But it’s often a bad idea to splurge on just one brand new item; once installed, it can look radically out of place amongst the rest of the kitchen’s features. Rather than downgrade the new appliance to fit with the rest of a kitchen, it’s just too tempting to upgrade everything. Stick with the same quality products across the board, and your home will look far more streamlined as a result.

Sometimes Thriftiness is Costly…
As we explained in our last blog post, there’s more to budgeting than just cutting costs wherever you can. It is entirely possible for the very cheap options to backfire on you and end up costing more to fix or replace. Cheap paint can peel, and cheap hardware may not be as sturdy. If you go with these options, it can initially seem like a fantastic deal, but you may end up with a messy, frustrating disaster after just a few months. Again, diligently research your options and choose the highest possible quality that your budget will allow.

…But Sometimes it Pays Off
Is someone trying to sell you on marble in the foyer, or mahogany hardwood floors? These costly materials can make a serious dent in your budget, even if they are quite lovely. While some cheap replacements are a bad omen, others are just common sense. There are lots of different hardwood floor tiles that are made from sustainable, eco-friendly materials which look just like old wood lumber, and cost a fraction as much. There are some high-quality composite alternatives to stones like marble and granite, so you can feel luxurious without spending like a millionaire.

During the housing boom of the early 2000s, many Americans followed a real estate routine: young couples or families bought small “starter” houses, did a few renovations to update vital areas, and then flipped the properties for a profit in order to upgrade to a bigger, more permanent home. But the US housing bubble proved to be exceptionally unstable, and the burst was part of what caused the global crisis in 2008, sending long-term ripples through the international economy and thoroughly altering the course of millions of peoples’ lives. Suddenly it wasn’t so easy to sell a house, even a modestly priced one. Homeowners, stuck in their current homes for the foreseeable future, are making different choices about renovation: rather than trying to increase the property value in the short term, they’re planning money-saving projects that will work for their family over time. Budgeting isn’t just about saving money; sometimes it’s about spending more now for something that will last a lifetime. Here are some examples of long-term considerations for your renovation.

Spray Foam Insulation
We’d be remiss if we didn’t mention the money-saving potential of good spray foam insulation; it’s a great example of long-term payoffs. When comparing the different types of insulation — fiberglass batts, blown-in cellulose, polyurethane foam, or other materials — many customers are often unsure about spray foam because of its initial cost. It’s true that it can be more expensive than the other options, at least at the outset, but budgeting requires you to overcome the strong instinct to only consider the numbers right in front of you and think about the future. The fact is that spray foam is more efficient at filling cracks, sealing drafts and preventing heat loss. A house with spray foam has lower energy bills each year; cheaper, less efficient materials may end up costing more in the long run.

Pre-Painted Siding
Siding must be able to withstand everything that Mother Nature can throw at it, without growing mold or cracking due to moisture. Many outlets now sell pre-primed and painted siding, which costs several more cents per foot. It may seem like a waste, especially for handy homeowners who feel that they can tackle a paint job. However, factory-finished siding boards tend to hold up much better over the long run, and do not require re-painting. Since they’re treated in the controlled environment of the factory, they aren’t prone to sun or wind damage while drying. Plus, you’ll save on the cost of painters!

Low Flow Toilets
Traditional toilets have always been a huge water hog; people who grew up on well water systems or septic tanks in the countryside will be familiar with the many rules necessary to conserve water and minimize flushing. Newer toilet models cut water consumption per flush by a significant percentage. While low-flow toilets may cost more than regular ones, they are big savers when it comes to utilities — not to mention the Earth!

Furnace Follies
So you’re renovating some major house systems and your contractor throws a curveball question: do you want to buy a new furnace? This can be a conundrum for many homeowners; new appliances cost a lot of money, and it can be tough to understand why you would want to replace a machine that’s not broken. But depending on the age of your furnace and the other upgrades you’re making, a replacement during renovation can save you money later on down the road. Old furnaces have a 50-80% efficiency rate; newer gas-forced models are about 90% efficient, if not more. This translates into dramatically lower energy bills! If you’re upgrading your energy systems in other ways, a new efficient furnace may be an excellent long-term investment; an older furnace is more prone to failure over time. However, a forced-gas furnace may be an unreasonably expensive choice if your home isn’t already set up for natural gas, as you’ll have to redo your entire heating system. Do your research and make prospective budgets for both the keeping and replacing scenarios; if the time and the materials are right, then a brand new installation may end up being a very wise decision.

Last week we looked at how the recent global recession has affected homeowners. The U.S housing market was a major factor in the financial crisis, and it forced millions of homeowners to radically change their future real estate plans, and start renovating their current properties in a new way. Renovation can be a much cheaper option than trying to sell in a flat market and almost half of polled homeowners have indicated that they’d be comfortable starting a remodeling project in 2013. So if you’re itching to make your old house feel like new, how can you do so without breaking the bank? Here are some tips from the professionals.

1. Avoid Peak Times When Hiring Contractors
Contractors work when there are jobs to be had, after all, the word ‘contract’ is right there in their job title! Both general contractors and specialized subcontractors will be busier at certain times of the year, when many homeowners want to get a renovation done; if you try to hire them during their peak work times, you may have to competitively outbid another project in order to secure the team. At the very least, you face the likelihood that you’ll pay about 5% more for a contractor’s service if you hire him or her during the warm months of spring and summer. Call around and see if there are contractors who will work for less during the off season, like right before spring begins.

2. Don’t Replace; Refurnish
A kitchen remodel can transform your entire home, and may even have a positive effect on the long-term property value. It’s no wonder that the kitchen is one of the go-to renovation options for existing homes. While it’s very tempting to replace everything in sight with brand new shiny appliances and the highest-end furnishings, kitchen renovations can rack up the bills very quickly. If your existing kitchen cabinets and counters are functional, but outdated, then you can save a lot of money by refurnishing the existing pieces. A new coat of paint and a glass-paned door can do wonders to brighten up dingy dark cupboards, and interior shelves can sometimes be replaced with new rolling shelves for extra ease of use.

3. Ask for a Bargain
When shopping for supplies or appliances, do your research; don’t go with the first deal you see. If you’re buying a lot of something, like tile for a bathroom or wood for your entire house’s floors, work with the salesperson. The same applies for general contractors; with the right attitude, you can sometimes get a better deal than you originally thought. What’s the key? Ask for a discount in a friendly, considerate manner; recommend the contractor to friends and family, which may get them more business. Be upfront about your budget and your goals, and ask how you can work together to achieve them. The worst that will happen is that the contractor will say no.

The financial crisis and Great Recession of the late 2000s affected nearly everyone it touched; it permanently altered the lives of millions of people across the world. Before the recession, and even before the unstable real estate bubble that contributed to the crisis, it wasn’t uncommon for middle-class Americans to buy a small starter home, let it gain value for a few years, and then sell it for a profit and upgrade to a bigger permanent location. When the crisis hit, many Americans found themselves seriously re-evaluating their starter homes; with almost no profitability in real estate, it was better to stay put. So while the house buying and selling market dried up, the home renovation industry saw an increase in upgrades, additions, and remodels. But the recession has touched home renovation too, in a few peculiar and fascinating ways.

Remodel for the Present, then Live In It
During the housing boom, a lot of renovations were done with the specific goal of increasing the property value for resale. In fact, an entire niche industry existed in which homeowners would buy a house, renovate it, and “flip” it for a profit. It seemed like a fun and easy way to make some money, but the post-recession housing market was a different story: there was no longer any guarantee in real estate investment.

Homeowners are hesitant to bet several thousand dollars on a remodel only to find that they cannot recoup the losses during a sale, so their reasons for renovating have changed. Rather than looking into the future, Americans are renovating for the present. They know that they’re likely to stay in their homes for many more years, and they’re choosing remodeling jobs that will provide immediate benefit to their families and improve their daily lives in general. Bathroom, kitchen, and basement renovations are popular ways to maximize a home’s potential in the here and now. Before the crash, an enterprising family of three may have upgraded a small bathroom with future owners in mind; now their remodel choices are more likely to be centered around their own needs and wants.

Do You Take $20s?
The state of the economy has caused Americans to look at their money very differently, and it’s not difficult to see why; in the worst parts of the crisis, no one was safe from layoffs. Whereas debt was regarded fairly casually in the early years of the decade, it quickly became clear that paying on credit was a quick way to lose necessary cash. With nearly everyone living on a budget, homeowners are waiting until they have all the money on hand before paying for a remodel. Builders are seeing more and more customers paying in cash, rather than putting the cost down on a credit card. They’re also paying for upgrades as they can afford them, instead of doing it all in one big expensive job and assuming they’ll have the means to afford future payments. As spending goes, this is a pretty positive outcome; it’s a much-needed reminder of the wisdom behind only buying what you can afford.

Blueprints For All
Before the recession, a major renovation was often planned by a professional interior decorator who would create a design based on the client’s rough ideas. But when your goal is remodeling on a budget, many homeowners are skipping the middleman and designing on their own. With hundreds of websites dedicated to home decorating ideas, homeowners are increasingly aware of how to maximize the potential of their space. This is an excellent way to save on the cost of a designer, though it’s a good idea to visit one with the final plan just to make sure it’s structurally and economically sound.

The United States economy is still extremely shaky, and the tremors ripple through all sorts of different industries and leave subtle marks all over the country. The housing market took a major hit during the global financial crisis of 2008, and has seriously affected how Americans define the idea of “home.” Housing is no longer assumed to be a good investment; there are many other factors to consider, and even as the economy takes steps towards recovery people are hesitant to spend again.

2013 has seen a new set of trends emerge, which some see as good omens and others see as bad. The housing market is recovering; existing home sales in December 2012 increased by 12.8% over 2011, and the annual price of existing homes has risen to the highest level since 2005. While banks have slightly tightened the predatory sub-prime lending and mortgage practices that helped cause the 2008 financial crisis, some growth is still occurring in the speculative markets, which economists fear could be another bubble.

While new home purchases and sales are on a cautious-but-optimistic rise, existing homeowners are increasingly turning to renovation projects to make their existing homes work for them. The realty market might be soft, but the remodeling industry is tough as nails, so they say. For many owners, it’s less risky to add on to an existing house they already own; it just makes sense to renovate bathrooms, kitchens, or basements, rather than trying their luck in the housing market.

The 2013 Houzz and Home Survey collected data from over 100,000 homeowners, and determined that 53% of respondents said that they were comfortable starting construction this year; there was a 7% drop in the number of people who wanted to wait and stabilize their finances first. Why renovate? While some do hold out a small hope that the projects will improve the property value of their house, most homeowners are understandably cautious about relying on anything to do with sales. Their upgrades are focused more on their present situation, improving their space in order to enjoy it as fully as possible.

Twenty-eight percent of the Houzz and Home respondents said they would be remodeling their bathrooms, which isn’t surprising; kitchens and bathrooms are high-traffic areas that can take a lot of use and abuse over many years. Luckily, the Remodeling Magazine Cost vs Value report estimates that minor kitchen remodels recoup about 73% of their initial cost, and bathrooms recover about 64%. So if you’re looking at your outdated counter tops and eyeing your hammer and nails, you’re not alone; renovations are definitely back in style.

Welcome back to our final post in this month-long examination of the history, science, and issues behind asbestos insulation. This building material is now infamous for being extremely toxic to humans; the tiny fibers in asbestos dust are easily trapped in the lungs when inhaled and can cause a myriad of deadly lung diseases. As we explored in the past few posts, asbestos became a very popular insulation material at the turn of the 20th century; but after hundreds of asbestos worker deaths, the public became fully aware of the danger behind their walls. In the 1970s and 1980s, the concern spun up into hysteria: asbestos was in our schools, churches, homes, and offices! Since then, sixty countries have banned the use of asbestos, but the United States is not one of them. While asbestos is highly regulated, it still has not been fully banned; it is unlikely to show up in a brand new home, although it may be in an older house that hasn’t been renovated in a long time. So, what do you do if you discover asbestos insulation in your home?

Recall the Sage Douglas Adams
It’s important not to panic; intact asbestos isn’t an inevitable health risk, and problems develop after extended exposure. It’s still worth testing your home; asbestos fibers can linger for years, and they can be found in a variety of different materials. Historically, asbestos has been used as a flame retardant in things like siding, paint, roof shingles, and tiles; not never mind asbestos insulation inside your walls. If you suspect that your house has asbestos, call the Environmental Protection Agency (EPA); they will either inspect the house or guide you to a certified asbestos professional. Either way, a team will come take samples of materials from your home to test them for asbestos. Never take these samples yourself!

If the tests come back positive for asbestos, should you pay to have it removed? That depends on a few different factors; while it is unnerving to live in a home with a carcinogenic material, in some cases you may be safest just leaving things alone. As stated above, intact asbestos materials aren’t necessarily risky; the problems come when the product is disintegrating or may be disturbed. If the material is in a high-traffic area, is very old and falling apart, or is located in a place you plan to renovate, then it should be removed. The project should always be done by a professional contractor with asbestos experience; DIY is not recommended.

If the asbestos product is in relatively good condition and located in an area where it’s unlikely to be disturbed, then it may be better to leave it in place; removal may cause it to crumble and release fibers into the air. Keeping the asbestos doesn’t mean you can’t protect yourself from it; the EPA suggests that you should seal or cover any remaining asbestos materials in your house. There are special products specifically made to coat asbestos materials and seal the fibers together permanently, preventing them from breaking loose; you can also have the asbestos wrapped up or closed off from the rest of the room. Whatever your situation, always consult with a professional. While asbestos can seem like a slumbering dragon inside your walls, it is a solvable problem and soon you’ll be able to breathe freely again.

Nowadays you’d be hard-pressed to find anyone who would willingly live in a house insulated with asbestos, but in the early 20th century the material was commonly used for homes, schools, and commercial buildings. Its fire-resistant properties made it seem like a “miracle mineral”; when the building industry boomed in the wake of the Industrial Revolution, asbestos mining became a very profitable business. But as we explored in last week’s post, asbestos is extremely hazardous to human health and can cause a myriad of lung diseases; many countries have banned it entirely. Modern history has plenty of examples of this sort of mistake: people discover a fascinating new material, it becomes wildly popular, and its dangerous side effects are only discovered after the fact. But in the case of asbestos, the health risks were known for a long time before any action was taken, and the scandal is still having an effect to this day.

Early Warning Signs
The Greeks and Romans used asbestos for many different products, fascinated by its flame-retardant capabilities. In the 1st century AD, they noticed that slaves who wove asbestos cloth were stricken with a mysterious illness of the lungs. However, asbestos-related health problems didn’t really become obvious until the material became widespread in buildings during the Industrial Revolution. In the early 1900s, four decades after asbestos manufacturing became a major industry, anecdotal observations began to emerge from doctors in America and Great Britain. When they autopsied asbestos miners and factory workers, they discovered large quantities of the material in lung tissue. In 1924, a British pathologist named Dr. Cooke began to publish case studies of workers who were suffering from an ailment he called ‘asbestosis’: the chronic buildup of asbestos fibers in the lungs. In a later study of 360 textile workers, he found that approximately 25% of them suffered from asbestosis and were at risk to develop several different types of lung cancers.

A Blind Eye and Scarred Lungs
The British government improved asbestos manufacturing regulations in response to the evidence, but United States asbestos industry leaders didn’t get the memo. That isn’t to say that they weren’t warned of the risks: quite the opposite. In fact, American asbestos companies knew fairly quickly that asbestos was dangerous. A life insurance company report from 1933 stated that 29% of employees at one major asbestos corporation had asbestosis symptoms; the same corporation had already circulated internal memos about worker fatalities as early as 1930. In 1932, the U.S. Bureau of Mines sent a letter to another asbestos manufacturer that stated, “…asbestos dust is one of the most dangerous [materials] to which man is exposed.”

The companies turned a willful blind eye to this evidence, and obscured the truth about asbestos for several decades. They settled worker lawsuits on the condition of total silence from both the plaintiffs and their lawyers, and frequently edited doctors’ articles to downplay the danger of asbestos dust exposure. In 1936, several large asbestos companies partnered and agreed to sponsor research on the health effects of asbestos, but retained total control over the disclosure of the results. The companies also removed all references to cancer from sponsored research in 1951. Asbestos use continued through the 1960s and 1970s; it wasn’t until the mid 1980s that public concern about asbestos exposure resulted in federal investigation and widespread action.

Stirring up Dust
After multiple studies and continuing public demand, nations began to take action in the 1980s. Asbestos is now listed as a controlled waste product under international law, and 60 countries have banned its use in whole or in part. In the United States, asbestos is highly regulated, but not banned. Asbestos litigation is one of the longest and most expensive mass lawsuits in American history; more than 8,000 defendants and 730,000 claimants have come forward for compensation. The use of asbestos, even in limited amounts, remains one of the most contentious and viciously debated issues in the building industry today. Next week, we’ll look at the details of US asbestos regulations, and explain what to do if you find asbestos in your home.

Nowadays, most people know that asbestos is extremely dangerous; it was once a very common form of building insulation, but has since been highly regulated in the United States and outright banned in several other countries. Last week we looked at a little bit of the early history and basic composition of asbestos; its resistance to fire and tensile strength made it a very popular building material from the 1850s onward. But all asbestos types are extremely hazardous to human health, and can cause a variety of chronic, difficult diseases.

Asbestos is quite durable in many respects, but the fibers are also incredibly thin – as small as 3 micrometers in width. By comparison, a human hair is 17-181 micrometers wide. The asbestos fibers naturally line up parallel with each other to form crystalline lattice structures. These crystals have three cleavage planes, two of which are much weaker than the third, and can be broken apart into fibrous fragments if sufficient force is applied. In fact, the structure is so soft that it can be broken with a simple finger crushing pressure, sending billions of tiny fragmented asbestos fibers into the environment. In buildings, asbestos can be disturbed and released via air erosion, vibration, fire damage, or abrasion. And if the settled asbestos dust is disturbed by human activities, it can fragment even further.

The tiny, needle-like fibers of the amphibole class are easily inhaled. In fact, asbestos occurs naturally in the air and in some drinkable water, and most people likely have several million asbestos fibers in their lungs. While naturally occurring asbestos may not have a significant effect on health, continuous exposure, through occupational handling or living in a house with asbestos insulation, is a different story.

When asbestos fibers are inhaled, they become stuck in the alveoli (air sacs) in the lung. The lung’s immune system releases macrophages, or white blood cells, which attempt to ingest the fibers and heal the lung using fibrous scar tissue. This is a normal process for the body. However, asbestos fibers are naturally resistant to digestion; the white blood cells eventually die off, releasing chemical signals to attract more white blood cells to clean up the mess and apply more fibrous tissue. The result is a fibrous buildup of asbestos in the lungs, reducing oxygen transfer to the blood; the scar tissue also causes the lung walls to thicken and lose elasticity. In 1924, a British pathologist named the disease ‘asbestosis’. Asbestosis is a chronic, slowly-progressing disease, and symptoms appear years or even decades after the initial exposure.

Asbestosis isn’t the only illness caused by asbestos fibers; they also cause abnormalities of the pleura (the protective outer lining of the lung), including hard plaques, calcification, and thickening. When the pleura is damaged this way, it impacts lung function. Asbestos also causes various types of lung cancer. Mesothelioma is a rare form of malignant cancer that infects the pleura; while it can occur spontaneously, asbestos exposure has been reported in about 70-80% of all mesothelioma cases. It’s theorized that asbestos fibers may be causing cancer not because of their chemical toxicity, but because they are small enough to tangle with cell chromosomes and disrupt natural cell division (mitosis), which can trigger tumor growth.

A single, high-dose exposure to asbestos is very unlikely to cause disease, but chronic or continuous exposure is absolutely detrimental to human health. Doctors knew about the link between asbestos and lung disease as early as 1906, but the United States didn’t start regulation until the 1970s and 1980s. Why did they wait so long? Next week we’ll examine the asbestos scandal that caused thousands of unnecessary deaths during the asbestos manufacturing heyday of the 20th century.