NEST

Season's Greetings from NEST

Be well, everyone.

 

 

Insulation Story Part II: Execution

Armed with the list of insulation contractors, I called around and made appointments for estimates with two of them. They visited separately, but had a lot in common. They both knew Cheryl and had worked with her before; I gathered from both guys that their relationship with her involved a fair amount of friendly negotiation.

Both wanted to see the report from Informed Energy, which I showed them each in turn, and we reviewed the insulation recommendations in some detail. Both had the same immediate reaction: insulate the floor, not the roof. It will cost less money and be more effective. I explained that I was planning to renovate the attic, and thought I might as well insulate the whole thing now. They remained unconvinced: how soon are you planning to renovate? Well, I had to admit it was going to be five years anyway before I was likely to raise the kind of credit (let alone cash) necessary to do the renovation, which would be extensive.

Here's the thing: my tall, steep roof naturally has a much greater surface area than the floor; any half-awake high school geometry student can tell you that much. A quick eyeballing leads me to guess that the surface of the roof is three times that of the floor, in which case I could expect to spend three times as much on insulating materials. Furthermore, if I insulate the roof and not the floor, I may be preventing heat from leaving the house but I am still allowing it to escape from my apartment into the attic where, for the time being, no one will benefit except the mice.

It didn't take me long to decide that insulating the floor was the way to go, especially after one of the contractors told me that if I insisted on insulating the roof, he wouldn't take the job, since he knew it would not be effective enough and he couldn't stand behind it.

Without going into excruciating detail about the two estimates, I can say that both contractors A and B seemed quite competent and professional. They proposed similar plans: to blow insulation under the attic floorboards and even, if I were willing to give up my attic storage, ten inches deep on top of the floor for increased R-value.

However, Contractor A seemed much more engaged on the topic of air sealing, pointing out all of the gaps and explaining exactly how he intended to seal them. Contractor B was pretty casual on the subject. Also, Contractor A was a little more convincing when it came to adding up the R-values of the various layers of insulation. And finally, Contractor A said he would perform a blower-door test before and after the installation to measure the effectiveness of their work. That showed me that he really meant business. For these reasons I chose Contractor A, even though his estimate of $3100 was about twice that of Contractor B.

In the end, Tom, the salesman, convinced me to let him cover the entire floor with an extra ten inches of insulation to attain a resistance value of R49! Readers, that is a full 13 points higher than the most heavy-duty of the plans suggested by Informed Energy. It is par excellence in the home-energy world. And it would cost about half as much. The drawback was that I would no longer be able to walk around or store things in the attic, but the fact is I really do have plenty of room in the basement. And when it came time to renovate (which, given the current economic climate, seems less and less imminent), I could simply remove the extra fill or—Tom's favorite idea—raise the floor by ten inches and simply leave all of the insulation where it was. 

We made a date, and the guys came out a few weeks later. It was super fun. There was a crew of at least six, maybe eight men. They showed up at about 10:00 a.m. First step: blower-door test, which confirmed what Cheryl and Aaron had told me, which was that my house was, in layman's terms, VERY DRAFTY.

Then they set to work on the air sealing. Remember all those gaps around the plumbing chases?

 

And how about the duct openings:

While that was going on, others built a walkway out of foam board and still others pulled up the hoses from the truck.

 

Once the gaps were sealed, the foreman led me around the attic (and basement) to show me their work. They were very thorough.

 

Then came the fluff:

 

Before long, my 90° attic looked like a winter wonderland.

 

There was a pink walkway through the middle of the attic, allowing me to reach the furnace and the front window. Any exposed ductwork, as well as the furnace plenum, was insulated with spray foam. The furnace itself, as well as the exhaust pipe, had to remain clear because they would get too hot. Otherwise, it was all covered up.

 

And out of the covered ground rose my gleaming chimney and toilet stack, looking for all the world like a scene out of Mary Poppins, only in winter:

When all was done, the foreman ran the final blower-door test. In the time it takes to spell Supercalifragilisticexpialidocious we determined that my house was (again, in layman's terms) only two-thirds as drafty as before! You may recall from my energy audit that it was initially three times as drafty as it ideally should be; I had improved my home's heating efficiency by 30%. When winter came, my heating bills (assuming similar weather and gas prices) should be 30% less. And my house should become a whole lot more snug.

The crew was gone by 5:00 p.m. I waved from the porch. It was only September, but I was ready for winter.

Readers, you must be thinking, it's winter now! It's been very cold. HOW'S IT WORKING? It's mean of me, I know, but I'm going to keep you on the edge of your seat for just a bit longer.

Insulation Story Part I: Plan

Readers,
I thank you for your interest in the results of my home energy audit. I know that many of you wondered whether I have followed the suggestions made by the Energy Detectives and whether they were successful. After keeping you in suspense for two whole weeks I am finally here to answer: yes and yes.

Insulation is complicated, readers. So many kinds to choose from! There's fiberglass, cellulose, petroleum- or soy-based spray foam, denim fluff, and mushrooms. A comparison chart rating these options according to price, R-value, and varying shades of green will show you a complicated matrix of pros and cons that could give you a bit of a headache (nothing to do with the formaldehyde). Fiberglass is cheap and easy to install but itchy and not very good for the lungs of the installers, nor is it as effective as, say, cellulose or, better yet, spray foam. The very dense, closed-cell spray foam gives you a lot of bang, but for a considerable buck. Denim is kind of sexy, but what about the mice?

Before I get into the particulars of the plan for my house, let me offer a brief primer on insulation:

R-value: The basic measure of insulation's effectiveness, it indicates resistance to heat flow. A higher R-value means more resistance, i.e. better insulation. It should be noted that every building material has an R-value, but of course 1/4" plywood, with its R-value of .31, is significantly less resistant to heat than, say, [fiberglass batting, which could give you an R-value of 3 or 4 for every inch of thickness.]

Fiberglass (approximately R3 per inch): not the favorite of energy-saving types or the health-concerned. While it's cheap, it doesn't have as much R-value as, say, cellulose or spray-foam. As mentioned above, it is uncomfortable to work with and sends tiny glass particles into the lungs of installers (koff, koff). It was traditionally made with formaldehyde, although this seems to be on the wane.

Apart from the health risks, it seems that fiberglass batting is less effective than other types of insulation. For one thing, when placed inside a wall, it fails to prevent air from moving up or down through the fibers. In a balloon-frame house (like mine), the base of a wall is open, as is the top. If you are going to install fiberglass batting inside such a wall, it's important to seal the wall at the top and bottom so that drafts cannot flow up or down.

Another problem with fiberglass batting as opposed to blown-in cellulose or spray-foam is that it cannot fill a space completely; there will always be gaps in between bats, allowing air to flow where you don't want it to.

Cellulose (R3.5 per inch): Made from recycled paper, this fluffy material is blown in through a large tube that comes out of a big truck. If used to insulate walls, it must be drilled and blown into a closed wall so that it can be contained. It's blown in very densely so that it is tightly packed. If used to insulate a floor, it can be blown into an open space and remain as loose fill. More expensive than fiberglass, less expensive than spray-foam. Requires professional installation.

Spray-foam (R5.9 per inch): Most spray-foam is made of polyurethane, a petroleum product. It is expensive, but has a very high R-value. Non-petroleum alternatives exist, the most common of which is made of soy. Cheryl makes the point that while it's nice that soyfoam is not made of petroleum, it has a lower R-value than the urethane sprayfoam, so if you use the same amount, you will have to use more heat, which will probably come from a fossil fuel. So there's a tradeoff, and Cheryl made the point that no studies have been done comparing the total petroleum cost or carbon emissions of the two types of spray-foam use. She also made the point that urethane foam doesn't use that much petroleum and that, once dried, it is inert, offgassing nothing but nitrogen, which is harmless, and water.

Rigid-foam Board (R7 per inch): Polyisocyanurate board comes in large panels (pink, in my experience) that are maybe the size of a sheet of drywall. Its rigid shape makes it structurally useful and good for retrofitting; this is the stuff you see on the exterior walls of a house being built or resided.

I should note that during my first conversation with Cappy Kidd, president of Informed Energy, he rejected my use of the term "green insulation," making the point that no product is inherently green; it's all a matter of using the right resources in the safest and most efficient manner.

When devising my insulation plan, Cheryl Pomeroy and Aaron Lund, the energy auditors, took into account my plans to renovate the attic at some point. Currently an empty, unconditioned space, my attic housed nothing but a furnace, a lot of ductwork, and a beautiful two-year-old chimney (it's amazing what $4000 can buy).

The furnace would soon need replacing and it was my plan to put the new one off to the side or out in the enclosed back porch and run new ductwork under the floor, leaving the floor open and ready for renovation, whenever I could afford to get around to it. Given these plans, Cheryl and Aaron thought it would make the most sense for me to insulate the underside of the roof, even knowing that I would eventually be cutting it open to build dormers. Better, they reasoned, to condition the attic space, which I would have to do anyway once I remodeled, and keep the floors clear: any heavy-duty insulation of the floor would probably end up covering the floor, making it unwalkable. Also, it is always good to keep your furnace inside a conditioned space so that the heat it generates does not escape to the outside.

Having established that, Cheryl drew up four plans:

Option 1: Add rafter baffles for ventilation between soffit (eaves) and roof ridge (this is to prevent the gathering of any moisture, which could turn to ice in winter and damage your roof). Add 1" rigid foam board to underside of rafters. Aaron explained that it's important to cover the rafters because, being made of wood, they conduct heat, acting as a thermal bridge. In other words, they will let heat out or in, probably whenever you least want it. Drill and blow in cellulose. Est. R-value: R18

Option 2: Spray-foam entire rafter cavity (spray-foam is entirely airtight and allows no condensation; therefore, no baffles are necessary). Then hang 1" rigid-foam board across the rafters.  Est. R-value: R30

Option 3: Cut and friction-fit unfaced polyiso board between the rafters; carefully seal gaps and joints with spray foam so that the entire system is air tight. Then add another layer of foam board across the entire system, covering the joists. Est. R-value: R29 with 1" board; R36 with 2" board

Option 4: To be honest, I did not entirely understand Option 4, but it basically involved sistering out the joists (extending them) by attaching 2x2 boards to the existing 2x4s. This would then create more room between the joists, into which you could fit more insulation. I suppose one advantage of Option 4 is that it would allow you to increase the R-value of Option 1 by using a greater volume of cellulose, which is cheaper than spray foam. Option 4 seemed a little overly complicated, so I did not consider it for long. Est. R-value: R28

This entire project would not be cheap, especially if I went with spray foam, which is quite expensive. As with so many things, you tend to get what you pay for: the most energy-efficient solution would probably end up costing me the most money. Cheryl guessed off the top of her head that Option 2, which would give me the greatest R-value, could cost as much as $6000; Option 1 would probably cost about one-third as much.

Cheryl and Aaron left me with a list of insulation contractors that they had worked with before, complete with notes about the particular expertise as well as strengths and weakensses of each company. They both made the point very strongly that air sealing would be every bit as important as insulation, and that any contractor I hired should take this seriously.

Finally, they urged me to call with any questions once I started the job.

Next up: Insulation Story Part II: Execution.

From Couch to Cuttlefish: Examining the Feedback Loop

My friend Julia is a conservation biologist who is constantly dismayed at the spoilage we humans wreak on the Earth, our home. “I don’t get it, Angie,” she said. “All other animals know not to soil their nests. Why should humans be different?”

Well, we don’t soil our nests, I said. Our houses are clean.

In fact, we go to terrific lengths to make sure that we have the cleanest, shiniest, newest-looking houses possible. Not only that, we spare no expense to ensure that our houses are as warm or cool, wired, well-plumbed and well-lit as we could wish. They are big. They have beautiful lawns; no bugs; paved driveways. We take great care of our nests. In fact, our nests are the envy of the animal kingdom; why do think all those mice and bugs are always trying to come inside? (Nice try, mice. Build your own.)

But when Julia says nest, she's not referring to our houses. She means the planet, or at least the parts of the planet that we inhabit. There are quite a few ways to consider that:

• house

• city lot

• block

• neighborhood

• city

• county

• state

• watershed

• power grid

• agricultural region

• food distribution network

• climate zone

• tectonic plate

• country

• continent

• trade route

• global supply chain

• planet

• solar system

and so on. The difference between the mouse and me is that the actions I take to build and tend to my nest reach far beyond the four walls of my house and wherever in my next-door neighbor's yard I pick up some couch stuffing.

My couch stuffing—let's say the cotton part—could very well come from Georgia or New Zealand or India. And the nature of industrialization, and even more the nature of global industrialization, is that I don't have to make the couch or worry about where the stuffing comes from.

If the mouse uses up all of the couch stuffing (fat chance), she'll see it with her own eyes and she will immediately feel its lack. That's what we call a feedback loop, and hers is very short. We have a feedback loop too, but ours is LONG. If I use up all the cotton—well, I'm never going to use up all the cotton, because I'm just one person. But let's say the entire couch-buying public uses up all the cotton. Or better yet, let's say, the couch-buying public creates such a demand for cheap cotton that Georgia and New Zealand and India use all kinds of pesticides to make it quicker and easier to grow lots of cotton.

This pesticide might degrade the soil in these places and run off into the groundwater, which could eventually make it to the ocean, where it might cause all of a certain species of fish to be born without a left fin. Then entire schools of fish, instead of swimming in straight lines, would start swimming in clockwise circles and interfering with the ocean currents. Eventually, some very observant meteorologist would notice that the typhoons off New Zealand are spinning backwards and the story would be picked up by the Chicago Tribune. A group of eager meteorology students from Northwestern would take a class trip to New Zealand, where one of them would pick up a local ichthyologist in a bar. After a weeklong romance, the ichthyologist would wake up one morning and say "Remind me again what you're doing here?" and he would tell her, and she would say, "Funny, that reminds me of this weird thing that's been happening with the cuttlefish in the last few years . . . "

For the sake of keeping this short I will say that her cousin is a cotton farmer whose child also happened to be born without a left arm, and they finally put two and two together.

Eventually, the New Zealand EPA outlaws pesticide use in cotton farming, raising the price of New Zealand cotton. The couch manufacturers then start buying their cotton from India, where the meteorologists have other things to worry about during typhoon season, but after a generation or so they too catch on and eventually the American couch-buying public is astonished to learn that couches have become more expensive, and they start buying used couches off of Craigslist.

Ahem. This is obviously a fictional scenario; in real life it would never happen so quickly. But you get the idea: the feedback loop is long and winding and subject to the caprices of fate.

The moral of the story is this: if we as a species think it in our best interests to behave as the animals do and keep our nest clean, we should not go to Crate and Barrel and buy a new couch when we need one. Better to simply go next door and rescue the couch in the back yard before it starts to rain.

Julia Frost Nerbonne, this is for you.