Monthly Archives: September 2022

Retrofitting with Radiant Cooling

Radiant cooling reduces or eliminates many of the faults of forced air systems: cost of operation, noise of air rushing through ducts or vents, drafty spots, allergens and dust being blown through your home, etc.

The need for a new cooling and heating system in my home has me looking at all the possibilities, now including radiant cooling and heating, also called “hydronics”.  I never thought that this would be possible because my house is, mostly, “finished”.  Radiant systems need to go in the floor before the floor goes down, right?  

Wrong!  It turns out that there are many options to installing radiant heating after the home is “finished”.  It just depends on how creative you can get with surface areas.  First, however, I’ll go over why radiant heating and cooling is superior to forced air systems, which encompass the majority of home heating and cooling systems today.

To me, this picture says it all.

Source : iapmo.org

The reason a tiny ¾” pipe can be equivalent to the big duct systems is because water is able to absorb more than 3,500 times the heat as the same volume of air!  Mind-blowing, right?  There’s a reason those big cast-iron radiators persisted in homes for all those years!  But instead of dealing with the thunk-crack-cluck of the radiators and boilers as they warm up, and being cold on the far-end of the room, now you can enjoy cool or warmth in silence as the room changes temperature from the floor up, ceiling down, or wall-out.  That’s right, you can install pre-made panels in the ceiling or on walls, which in general are way more accessible than floors.  For this reason, I’m going to focus on ceiling and wall panels and ways to work them into your existing home.  Also because I live in the southeast US, I’m going to focus on cooling, because radiant cooling is unconventional but very needed here! 

Messana is an Italian company focused on radiant cooling.  They have a number of high-end residences and office buildings portrayed as Projects on their website, and I can see why.  Their “Ray Magic” panels bridge the gap when figuring out how to place hydronics in the ceiling, because they have gypsum board (drywall) on the surface that faces the room, the tubing embedded in lightweight aluminum panels in the middle, and 1-½” of styrofoam on the side that faces the ceiling (yup, the same width as a 2x4).  Ray Magic panels are the “body” of the system, but a sophisticated “brain” is needed so that you can segment the home or office into different zones, sense the air in the different zones and control the temperature and speed of the circulating radiant fluid so that the zones stay comfortable and above dew point (to avoid condensation).  This is what the Messana Climate Control Platform does.  Although hydronics technically does not move air around, many times “air treatment” is needed so that the need for fresh, dehumidified air is met.  For this reason, Messana offers a range of Air Treatment Units (ATUs) for accompanying ventilation.  To see their products installed, check out these two videos here and here…and the system was installed in Austin, TX.  Austin can definitely speak to needing dehumification! 

Now, comparable with other things Italian, Messana installations are on the expensive side.  According to their FAQ page, the equipment costs between $15-20 per square foot, with prices of $40-45 per square foot installed (this is based on the total square footage of your home, although the panels typically cover only 60% of the ceiling).  For a renovation, this can add up to a lot of $$$, so following are some other alternatives.  As mentioned above, radiant floors can be installed over existing subfloors.  Here are some products to make the installation easier: 

• Thermalboard is a ⅝” thick MDF board with aluminum coating and channels for 3/8” PEX tubing.  The company WarmZone uses your floor plan to create and ship the boards to you for a custom installation that looks to be fairly simple for the average DIY homeowner.  The boards are glued, then nailed down to wood subfloors, or only glued to concrete subfloors.  Costs are about 2x of a standard baseboard radiant heating system, but 30-40% savings in long run.  The pros: the product is lightweight and easy to install on the floor or on walls.  The downside: MDF absorbs water, which with a product that uses water, seems to be, well, not too smart.  Also, MDF is manufactured with significant glues, which emit VOCs.  Thermalboard specifically tested their product and it does not off-gas formaldehyde.  

• Warmboard R, which uses slightly larger tubing (½”) with larger spacing and thicker aluminum, but costs approximately 2x as much. 

• EcoWarm RadiantBoard is a similar product to Warmboard R but uses plywood as the substrate.  The aluminum thickness is comparable to Thermalboard, and it uses ½” PEX.  It costs approx. 35% less than Warmboard R.  It tends to discourage use of its product with radiant cooling, however.

• Uponor has a variety of products in radiant flooring: Quik Trak, which is similar to the above products as a plywood and aluminim substrate for the PEX, Fast Trak, which is a knobbed mat that will secure the PEX in any configuration, and Joist Trak, which can be nailed to joists for sub-floor heating and cooling. 

• Rehau, a German company which is one of the pioneers of radiant-floor heating, has products that allow direct installation of flooring over them (RauPanels), within a joist space (RauPlate) or within a concrete overpour. 

• Heat-Sheet is a grid system for laying out your own radiant flooring made of high density expanded polystyrene (EPS). It can be used under poured concrete or gypcrete (see next).  The panels are lightweight and interlock to minimize movement.  The website shows it being used under driveways (no more ice!) and swimming pools.

Of course, installing the radiant tubing is only half the work, because it needs to be protected with a durable covering that is not too insulative.  Radiant flooring can be covered with any number of durable flooring options, including hardwoods, tile, carpet, finished cement, etc.  Here are some options:

• Gypcrete: You can embed radiant tubing in a mixture of gypsum plaster, Portland cement, and sand, known as gypcrete.  Therma-Floor is a trade name of this product.  Installation takes significantly more time because it doesn’t come in a snap-grid, and takes time to cure.  It also must be installed by a professional crew. 

• With tile, laminate and carpet systems, a plywood underlayment will be needed to help provide support over the tubing.  Here are some example installations from Thermalboard.  The article also gives R-values for sample materials.  Remember, when covering a radiant floor, you’ll want your R-Value to be as low as possible, so that you’re not “insulating” the heat or cold within the flooring material!  TheSpruce.com recommends that ceramic or porcelain tile is the best material for covering a radiant floor, as it conducts heat (and cool) most efficiently.  On the other end, carpet is the most insulative and worst choice for covering.

These are just a sampling of radiant products on the market.  With new products and technologies released every day, don’t take your pre-existing home features as limits when it comes to the important decision of heating and cooling.  Research, ask, test and compare so you can find the most healthy, comfortable solution for your home!

How healthy is your SprayFoam?

Sprayfoam has been a huge player in the home insulation industry, and is projected to grow by 4-6% CAGR through the next decade (marketsandmarkets.com).  It is used as insulation (R-3.8 for open cell and R-7 for closed cell), and can be an air barrier and/or vapor barrier when applied properly (Johns Manville).

Bud Offermann is President of Indoor Environmental Engineering, a building science consulting firm in San Francisco.  He gave a very informative interview on healthyindoors.com in July of this year, on material from a paper he presented at the International Society of Indoor Air Quality and Climate’s (ISIAQ) Indoor Air 2022 in Kuopio, Finland in January.  You can read and download the paper here.   Because of his experience with high variability in the application of spray foams and ensuing problems with chemical emissions, he can’t recommend spray polyurethane foam (SPF) to insulate your home.  This article is based on his presentations.

Some SPF installations result in chemical emissions that cause odor and irritation and that are expected to persist for decades.  Therefore, it’s important to research and consider before contracting for spray foam insulation. Can you imagine ruining your well-loved or newbuild home with something as permanent as spray foam?  

There are two components of spray foam, which we can term A-side and B-side.  These are stored in two different containers and fed through two hoses to the spray gun, where they are mixed as spraying takes place. The A-side is isocyanates, which are very reactive; they evaporate quickly and don’t hang around after application.  These chemicals are mainly a problem for the applicators, who need to wear fresh-air breathing apparatus to avoid breathing them.  The B-side is a resin which has the fire retardant, reactants and additives.  These are the components that remain in the installed foam and off-gas over a period of time. 

The main chemicals causing problems are allylchlorides, the fire retardant TCPP, BDMAEE (an amine created by breakdown of TCPP), and 1-Chloro-2 Propanol.  These can cause eye and nose irritation.  The emissions can last at a slow rate for 50-100 years.  Temperature causes an increase in irritation and odor (summertime is worst). 

Causes of offgas problems are hypothesized to include:

• If the two components are mixed in the wrong concentration, it will not cure properly.  For example in closed cell foam, too much A makes the foam fragile and brittle.  Too-much B makes the foam too gooey. 
• Storage of the resin (B) in the warehouse possibly allows water contamination (hydrolysis of the TCPP).  Addition of water can create 1 Chloro-2 Propanol or allylchlorides.   These substances can cause allergic reactions and continue to occur months or years later as the foam off-gasses.
• Closed cell foam should not be installed in thicknesses greater than 3”, otherwise the interior of the foam layer will not cure.  Multiple passes are needed to achieve thicker application, but sufficient curing is needed between layers, otherwise uncured foam inside the layers will continue to off-gas. 
• Sometimes the applicators switch between open and closed cell foam without changing the transfer pump or hoses.  They only change the B-side (resin) drum and start spraying, which makes the product in the pump and hoses an unproven mixture of open and closed cell.
• Sometimes applicators buy the B-side and then add more chemicals for “winterizing” the foam.  This is adding chemicals after-market, which will invalidate any warranty on that foam.

If you are experiencing bad air quality after spray foam application in your home, the first step is to test.  Testing will let you know the level of the problem and if litigation is needed, proper air testing is required.  Air samples are gathered with windows and doors closed, supplemental attic ventilation turned off, no air cleaners running, and normal house HVAC running. There are specific chemicals to test for, including VOCs excluding isocyanates and formaldehyde, also samples should be gathered in different rooms and outdoors as a baseline.  After the air is sampled, an 8x8” chunk of foam is removed without disturbing the surface of the foam, to send to the testing facility (Berkeley Analytical is one recommended lab).  You should also get the material safety data sheet (MSDS) for the foam, which should disclose all non-proprietary ingredients.

If emissions of SPF continue to cause problems, as an expert in home inspection and remediation, Mr. Offermann states there are two solutions: 

• remove the insulation and the substrate, because the substrate absorbs some of these chemicals (very costly) OR
• attach a foil faced gypsum or rigid foam board against the trusses/studs to contain/reflect the gasses. 

If you are sensitive to chemicals, spray foam is probably not the best choice for your home.  However an alternative is to use foil-faced foam board.  Because the foam board is made in the controlled environment of a factory, then tested, you can get the same insulative properties with much less chance of continual off-gassing .  Foam board doesn’t have air barrier properties because of the way it’s installed, but air barriers can be achieved with other non-chemical methods.

In conclusion, further research on the chemical reactivity of TCPP and its suitability as a fire retardant is needed.  Where is hydrolysis occuring?  Proper storage of the B-side product and training of the application team is necessary because once spray foam is applied, emissions are unhealthy and removal can be very costly.   

Wall covering products that resist mold and mildew

When my kitchen faucet caused a leak under the sink and mold spotted the drywall behind it, I thought, with what material can I replace the drywall to make it less mold-friendly?  Under the sink is a dark, damp area where water can intrude again.   Searching my local big hardware store, all I came up with was fiberboard that had a melamine coating on one side.

Doing some more research online, however, uncovered several more options.   These are not only for under sinks, but garages, basements, utility closets, porches, and anywhere that moisture can be an issue.  

Using large panels instead of smaller cladding units (tiles, boards, etc.) minimizes labor, opportunities for water ingress, and also dust, which is always an inhalation hazard for the installers and anyone else in the area.  

Interior Cladding

Trusscore is a new PVC product that not only resists moisture, it reduces installation time, labor and cost when compared with drywall.  Trusscore panels are ½” thick, so that they are the same thickness as drywall.  They are so named because of the truss-like structure inside to give them strength with flexibility (they bend enough to facilitate installation inside channels without creasing).  Once you see this product being installed, who would ever want to go back to the labor intensive, dusty, mold-prone drywall process again?  I really like the clean simplicity of this product.  My major concerns with having it in residential spaces were:

• VOCs and off-gassing: how much harmful pollutants will it pass into your indoor air?
• Penetrations, because inevitably, someone will want to hang a picture or shelf on it, and then you have visible, difficult to patch holes in it.  
• What about changing the color? 

However, the company has integrated solutions into each of these problems.  

• Trusscore addresses IAQ here: “Trusscore Wall&CeilingBoard, RibCore, and NorLock products are all low-VOC compliant, including low formaldehyde, meaning it won’t off-gas and ensure a safe and healthy space for occupants. In addition, the installation of Trusscore products does not require potential VOC sources like glue or paint for a finished installation.  Each product has been tested according to the California Department of Public Health (CDPH) Standard Method v1.2 testing standard. This is the leading VOC standard used to evaluate VOC emissions from building products such as flooring, suspended ceilings, insulation, wall panels, paints and coatings, and wall coverings. The CDPH standard is referenced by some of the most widely used green building rating systems and green construction codes including USGBC LEED, CalGreen, and more.”  Still, in a fire, I would RUN out of any area that was covered in PVC...I’d say this is definitely not the material to cover any space where welding or high heat hobbies occur.  Also, I would hesitate install to it in high ambient heat places like Las Vegas or the southwest US (it’s plastic, after all)!  
• Trusscore makes slatwall, which makes it easy to hang things (especially useful in garages and utility rooms)
• All the panels come pre-finished in a durable white or gray coating, and painting guidelines can be found here (Painting requires special primers so that the paint will stick).  The benefit of painting: if you can paint it, you can also patch it!

Duramax PVC Wall Panels are very similar to Trusscore, but they come in 16” widths instead of 48” widths.  They also do not have any slatwall systems, recommending instead to use hangers similar to drywall hangers to permanently hang anything.  The cost of Duramax is less than Trusscore ($2.70/sf vs. $3.60/sf). They do not have any VOC emissions information on their website or MSDS other than protection guidelines against dust generated while installing it.

MSD panels have a variety of natural and futuristic textures (brick, tile, wood, stone, etc.) for a moisture-resistant cladding for interior walls.  The video on this page contains a little bit construction, a little bit artistry as the installers hang the panels and patch the seams to make the brick wall look completely congruent. As an artist, I do like these for the realistic looks they form.  Unfortunately, they are in Spain!

EverBlock and EverWall products are like giant Legos (with these why would you want to “grow up”?).  Everblocks are made of High-Impact Polypropylene Co-Polymer (“no-break”) with UV Inhibitors added for outdoor use.  EverBlocks are recyclable. They don’t offer much insulative quality (R-2 equivalent), but they are hollow and internally reinforced.

Formica lives on!  Formica HardStop has the great variety of colors and patterns of traditional Formica, but instead of the traditional fiberboard backing that is susceptible to moisture ingress, HardStop has a fiberglass backing that makes it more durable and water-resistant. It can be applied to drywall, plywood, and particle board (which are susceptible to water) or to cement or cement board. HardStop panels are thin and flexible like the original Formica, so they do need a structural element for reinforcement behind them.  They also require adhesive (looks messy to me!).

DriCore Smartwall is a similar system that incorporates an insulated layer on the back of the panel.  Very genius, however, the system uses drywall in the panels, and wood cleats to install it and has wood interlocking sections within the panels.  Here is a video on the installation of DriCore Smartwall, which also uses patch material to make a seamless wall.

Exterior cladding

The more I read about building science, the more I see imperfections in “the way we always did it”.  There are many traditional finishes for commercial and residential buildings, but the gold standard calls for a “rainscreen” type structure that applies the cladding to a hidden track system, so that air can reach behind the rainscreen and dry things out.  Think about a rain fly for a tent, or a double roof system.  The air buffer separates water and extreme heat or cold from the exterior of the house, making for a longer-lasting house!  In his article “The Perfect Wall”, building scientist Joe Lstiburek defines the elements of this wall and how they are constructed to resist rain, snow, humidity, air intrusion, mold, heat and cold, etc.

Here are some products that work as rainscreens:

• Nichiha: this company was founded in 1956 in Japan but now has an office and factory in Georgia.  Their cement fiberboard siding comes in architectural panels or premium planks and uses a hidden track system.  It is an upgrade to “Hardy Board” and the many imitations of it, because it “floats” on the track system with that air buffer behind it.
• Ceraclad is a triple-coated ceramic and cement rainscreen with its own installation system. The panels are self-cleaning, with a photocatalytic coating that actually purifies the air!  The coating decomposes car exhaust and other pollutants in the air (NOx and SOx) and turns them into NO3 harmless polyatomic ions leaving the air cleaner.  According to the website, a building with 10,000 sf of external Ceraclad coating is the equivalent of 68 poplar trees!  10 Ceraclad panels are the equivalent purification to 1 poplar tree.  The coating also inactivates viruses and bacteria at its surface. 
• Knight Wall Systems provide the hidden tracks to install your rainscreen.  They have three different types of attachment to accommodate many different types of cladding.  Although mainly commercial, this system could be used for high-end residential homes as well.
• Monarch Metal offers cladding systems with all kinds of finishes including HPL Phenolic, stone, fiber concrete and more.  Their hanging system contains high quality “Z-clips” which are similar to french cleats that allow you to hang the facade without screwing into the face of it, also interlocking panels as you install them.

These are just a sample of ways to get less mold growth in damp areas, relying on 1) materials that don’t sustain mold and 2) siding that incorporates ventilation.  It’s building science at its best!

Micro- and Nanoplastics are everywhere

Children especially are moved with compassion for animals.  I remember learning as a child that non-biodegradable plastic often ends up in the ocean, and sea animals like birds and fish can get entangled in plastics like 6-pack rings, so I started to cut apart the rings before throwing them away so that the animals wouldn’t strangle.  Later I learned that some plastic bags were being manufactured as “biodegradable”; this was some relief to my mind.  However, the newest question is, into what are they degrading?   It turns out that plastics are coming back to us in invisible ways when they break down into microplastics and nanoplastics.

Microplastics, artificial polymer particles with size less than or equal to 5 mm, were initially reported in 2004 (2022 study: Nanoplastics and Human Health: Hazard Identification and Biointerface).  They are produced from disintegration of plastic products, from the ubiquitous plastic shopping bags to a child’s toy stroller to an empty jug of laundry detergent. Small millimeter-sized pieces of plastic seem like they would produce a lot of plastic “sand” that could be filtered out of water or even pass through our digestion system unchanged.  Yet microplastics are not the end product; nanoplastics are.  Nanoplastics are particles with a size ranging between 1 nm and 1 μm, which cannot be seen by the human eye.  

Nanoplastics come from a lot of different sources and some surprising ones.  We’ve written about different harmful nanoparticles that can be emitted into the air and water: from ceramic coated cooking pans, 3D printers, dust particles, from combustion engines, graphene, household cleaning products, and microfibers that get released in your washing machine and dryer (some of which are actually nanoplastics).  Here’s a new one to us: huge amounts of nanoplastics are released by car and truck tires every year by the simple acts of driving and braking.  

According to National Geographic, “Tires are actually among the most common plastic polluters on earth. A 2017 study by Pieter Jan Kole at The Open University of The Netherlands, published in the International Journal of Environmental Research and Public Health, estimated that tires account for as much as 10 percent of overall microplastic waste in the world’s oceans. A 2017 report by the International Union for Conservation of Nature put that number at 28 percent.”

“Today tires consist of about 19 percent natural rubber and 24 percent synthetic rubber, which is a plastic polymer.”  Considering that each (car) tire will lose about 1.5-2 lbs of weight over its lifetime, which is the wear of rubber and plastics from it, millions of tires on our roads add up to tons of micro- and nanoplastics.  

Nanoplastics are dangerous to the environment and to us.  The following diagram shows the many ways our bodies are exposed to them:

The benefits of living upwind

I can only think of a few times where being downwind was preferable.  If you’re a hunter, you’d want to be downwind of your prey so it won’t smell you and run away.  I didn’t mind being downwind of the coffee roasting plant when I lived in New Orleans because of the good smells.  In all other cases (maybe I’m missing one?), being upwind is the place to be. 

In several articles we’ve described the ways that nanoparticles and pollution can infiltrate our homes, and the effects that it has on our health.  Therefore, we advocate for “living upwind” of the many potential pollution sources in our cities and country today.  It’s just fresher, cleaner, and healthier.  Here are some reasons why:

• Major cities: many of the world’s largest cities (including London, Paris, New York, Toronto, Bristol, Manchester, Oxford, Glasgow, Helsinki and Casablanca)  have poorer “east ends” because the prevailing winds blow pollution from west to east. (study)

• Fossil-fuel power plants:  In a study surrounding a coal-fired power plant located in Pennsylvania, it was found that infants born to mothers living as far as 20 to 30 miles downwind from the power plant were 6.5% more likely to be born with a low birth weight (i.e., birth weight below 2,500 grams) and 17.12% more likely to be born with a very low birth weight (i.e., birth weight below 1,500 grams).

• Refineries and oil wells:  In 2020, 13 refineries in the US released benzene, a cancer-causing toxin, in amounts above EPA action levels.  (environmentalintegrity.org).  Unfortunately refineries have emergency releases of chemicals at various times, sometimes just because of a power failure.   In our post on emissions from oil wells, we reported that harmful VOCs and particulates are being released continually, and these increase the risk of respiratory and other illnesses.  

• Ports and airports: The California Air Resources Board (CARB) estimates that there are 3,700 premature deaths per year directly attributed to the ports and goods movement activities statewide and approximately 120 deaths per year associated with diesel particulate matter emissions from activities at the Port of Los Angeles and Long Beach. The economic cost associated with these deaths as well as for medical care for illnesses and missed school and work days is an estimated $30 billion annually. (The Impact Project, 2012 paper).  Noise and light pollution are also results of living near a port.

• Major highways: there are “statistically and economically significant effects of exposure to near-roadway pollution on mortality amongst the elderly” according to one study, however the pollution is also harmful to people of all ages, such as young children, who are susceptible to asthma, and adults, becasue exposure to fine particulate matter is associated with high symptoms of anxiety and antidepressant use. (discoverymagazine.com)

• Volcanoes: volcanic vents can emit gasses on an ongoing basis that contain toxic components such as sulfur dioxide (SO2: smells like a struck match or fireworks), hydrogen sulfide (H2S: smells like rotten eggs), hydrogen fluoride and hydrogen chloride (HFl and HCl, smell strong, irritating and pungent), and carbon dioxide and radon, which are odorless but also dangerous. (International Volcanic Health Hazard Network)

What if you can’t live upwind?  Then try to employ some techniques to prevent the outside pollutants from penetrating your home:

• Mitigate the stack effect by sealing the building envelope.  Contrary to popular opinion, just adding more insulation will not stop air leaks, because they are propelled by air pressure differentials, not just temperature differentials.  Pressurized will find a way through insulation if there is a leak in the building envelope.

• Make green your favorite color!  When possible, surround yourself and your property in trees and/or plants because they absorb VOCs and particulates, and create a myriad of health benefits for your mind and body.

• A 2011 study entitled “Improving Health in Communities near Highways” hosted by Tufts University suggested filtration as the number one method to reduce ultra-fine particles indoors.  Filters for residences and schools near busy roadways should be Minimum Efficiency Reporting Value (MERV) 14 or above, mainly because the ultrafine particle removal efficiencies of filters with lower MERV ratings are not reported.  Another method was to relocate building intake air vents to the downwind side of the building.  

• Bipolar ionizers like The Whole-Home Polar Ionizer, Germ Defenders and Air Angels  cause small nanoparticles to stick together and drop out of the air, to help you avoid breathing them in.