Not a Faraday Cage

13:10 Tuesday, 17 March 2026
Current Wx: Temp: 21.67°F Pressure: 1011hPa Humidity: 69% Wind: 16.13mph
Words: 673

Claude dispelled any illusions I had that an ICF home with metal siding and roofing represented some protection against EMP.

Alas.

If you're interested, here's the response minus my prompt. (Please forgive the markdown detritus. I'm not going to clean it up. And yes, Mitzi's flight is delayed again. Hopefully taking off within the hour.):

[Ed note: Learn something new every day. Tinderbox renders markdown to html on export, so no detritus. Maybe it's done that all along. I don't know because I never use markdown, because "plain text" isn't so precious to me.]

Yes, I understand the question precisely. You're asking whether the passive electromagnetic properties of the structure itself — not any intentional hardening — would incidentally provide EMP attenuation sufficient to protect unconnected electronics from the E1 pulse component of a high-altitude nuclear EMP (HEMP) event.

It's a genuinely interesting physics question. The honest answer is **partially, but probably not sufficiently**.

1. What You Actually Have

An ICF home with continuous rebar, metal roofing, and metal siding does create **a partially conductive enclosure**, but it falls short of a true Faraday cage in several important ways:

• What works in your favor:**

- The rebar mesh in ICF walls is continuous and interconnected — if properly bonded at corners and intersections, it forms a conductive lattice throughout the wall assembly

- Metal roofing and metal siding add conductive surface area

- The overall mass and conductivity of the structure would attenuate — not block — an incoming electromagnetic field to some degree

• What defeats it:**

- A Faraday cage requires a **continuous, gapless conductive enclosure**. Your home has windows, which are essentially large holes in the conductive shell. The E1 pulse (the fast, high-amplitude component that destroys electronics) has wavelengths in the range that passes through window-sized apertures with relatively little attenuation

- The rebar is embedded in foam and concrete — it's not a tight mesh on the exterior surface. Effective Faraday shielding requires the conductive layer to be on the **outside** of the enclosure, and mesh spacing needs to be small relative to the wavelength of concern

- Metal roofing panels are joined at seams, not continuously welded — there are gaps in the electrical continuity

- The rebar in different wall panels may or may not be electrically bonded to the rebar in adjacent panels, and almost certainly isn't bonded to the metal roofing and siding as a unified system

1. The E1 Pulse Specifically

A HEMP event has three components — E1, E2, and E3. E1 is the one that destroys solid-state electronics. It's an extremely fast pulse (rise time in nanoseconds) with a broad frequency spectrum peaking roughly in the 1–100 MHz range. Effective shielding against E1 requires attenuation of **40–80 dB** depending on how hardened you want to be. A proper Faraday cage with tight mesh and sealed apertures achieves this. Your incidental building structure might achieve **10–20 dB** of attenuation — meaningful, but not protective in any reliable sense at 100 miles from a burst optimized for EMP effect.

1. What Would Actually Protect Electronics

A properly constructed Faraday enclosure inside the home — even something as simple as a **metal garbage can with a tight-fitting lid**, with electronics wrapped in a non-conductive layer inside — would be far more effective than the building structure itself. The key requirements are continuous conductive enclosure, no gaps larger than a few centimeters, and the protected electronics **not connected to any external conductors**.

Military and government EMP hardening uses welded steel enclosures with filtered penetrations for any necessary connections — a very different standard than incidental building construction.

1. The Short Answer

Your ICF home with metal cladding is probably better than a wood-frame house with vinyl siding — but that's a low bar. It would not reliably protect unconnected electronics from a well-designed HEMP event at 100 miles. The windows alone are a sufficient defeat mechanism for the E1 component. A dedicated Faraday enclosure for critical electronics, inside the home, is the appropriate solution if that's a genuine concern — and it costs almost nothing compared to the building itself.

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Tundra

09:48 Tuesday, 17 March 2026

Current Wx: Temp: 21.7°F Pressure: 1011hPa Humidity: 69% Wind: 16.13mph
Words: 850

It's 20°F out there, but 20 knots of wind makes it feel like 8°. I've gotten some use from my ice cleats. Back porch is covered with rough ice. Probably not a slip risk, but you never know. Went out to the garage for some salt. Don't want Mitzi taking a spill when she gets home.

I'm feeling fairly unproductive, so I figure I'll just do some blogging.

I wonder if Paradise was really intended to be a "one and done" limited series. Because it seems to me that they didn't really have a long-term story arc. I mean, time travel? Really?

I still like the characters, and the survival stories, but it just seems like they were reaching for ideas off the shelf, The Man in the High Castle in this case. Though I suppose that wasn't time travel so much as a parallel universe thing.

Monarch is something of a profound disappointment. It has some good ideas, but the execution is sloppy and the storylines are too disparate and weakly developed.

I watched Cold Storage the other night, and that was delightful. It reminded me a lot of Tremors. A "buddy pair" protagonist, interesting supporting characters. I think Tremors has the advantage of a truly novel "monster." Cold Storage gives off some The Last Of Us vibes, which isn't entirely unwelcome. Just a great B-movie experience you won't regret watching if you're into that sort of thing.

And I am.

Today should be a workout day, but I'm giving it a pass due to lack of sleep and picking up Mitzi. But I've been doing pretty well overall. Sunday I did 20 minutes on the elliptical followed by an arms workout. My legs are still complaining this morning. I'll head to the gym tomorrow for more time on the elliptical and "leg day." Gotta get in shape to survive old age.

Speaking of longevity, I've also made some changes to my diet and beverage consumption. For most of my life, I've had a diet soda habit. It was my preferred caffeine delivery vehicle. To try to be a somewhat more responsible diet soft drink consumer, I switched to Soda Stream products, so I wasn't generating as much plastic waste.

I ran out of syrup back in January and haven't bought any since. I've switched to drinking green tea. Apparently you're supposed to have three cups a day to have any real health benefits and I'm only having two. That may change when it gets warmer. I was surprised at the extent to which a hot cup of tea will warm you up. I normally get up and put on a sweatshirt over my long-sleeved thermal undershirt. After having a cup of tea, I have to take the sweatshirt off for a little while. Other than that, I mostly just drink water or an occasional hot chocolate.

As for my diet, I've been focusing on fiber to feed my microbiome. For the past few years I've usually eaten the same thing for breakfast every day, with few exceptions. Two eggs, spinach, baby Bella mushrooms, black beans and occasionally onions. Often, but not always, topped with avocado and always Sriracha. Seems like a generous amount of fiber-rich foods.

This winter, I've been switching it up a bit with oatmeal with blueberries and walnuts. Sometimes bananas. About a tablespoon of buckwheat honey too, which is perhaps a bit too generous.

I've tried overnight oats for the first time this week. They're pretty good! The nice thing is you can make three servings at once the night before. I went out and bought a set of Anchor-Hocking 2-cup glass storage containers, which are a good size. I see a lot of folks using Ball jars, but I prefer a shallower container. I do a cup of whole, rolled oats, a tablespoon of chia seeds and some cinnamon. I shake that up pretty good to get the chia seeds spread out. Then a generous tablespoon of plain greek yogurt, a cup of milk and a generous teaspoon (I'm trying to show restraint now) of buckwheat honey. Stir all that up, cover it and stick in the fridge.

The first morning I tried it, it was great! I added blueberries, raspberries and walnuts and stirred them all in. The second morning it had thickened up quite a bit, so I added a splash more milk and stirred that in before adding the berries and walnuts. Just finished the third bowl this morning, still great.

Less prep and cleaning than the egg breakfast, and less risk of exploding oats in the microwave. (I've learned to keep the power at 40% to avoid that.)

I try to do something similar with lunch. Yesterday I did the egg breakfast and had the overnight oats for lunch. When I make a sandwich, I try to add a lot of veggies.

Am I any healthier? Who knows?

"Do your best, the rest is not up to you."

The beat that can be counted is not the beat, but the beat goes on...

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Weather

07:53 Tuesday, 17 March 2026
Current Wx: Temp: 19.8°F Pressure: 1009hPa Humidity: 73% Wind: 17.18mph
Words: 953

Mitzi was supposed to get in last night about 2230, but she got stuck in Detroit. Not exactly stuck so much as her flight kept getting delayed to the point where she called an audible and booked herself on another flight out today, and then tried to find a hotel room.

Her flight was ultimately cancelled, so it was a good call. She is scheduled to arrive in Elmira today at 1330, which at least means I won't be driving in the dark.

Had a productive interaction with Claude yesterday regarding the new house. I'd made a spreadsheet with various size floor plans, from 28' to 30' wide, 44' to 46' long, and the cost of each at our quoted rate.

Then I described what we were trying to accomplish to the AI, and asked if there was a "sweet spot," regarding the "ideal" size. It offered some useful feedback and pointed out that a loft and a basement consume a good deal of main floor square footage just for the stairs, figuring 45 sq ft per stairwell. I don't know if that's a hallucination or not, but it does give me something to ask the designer about. I'm not dead set against a loft, but I wonder if it's more trouble (and cost) than it's worth.

Keeping the loft option open, for now, I started working on a 30'x46' floor plan. It's an exceedingly tedious program, and I think I'd really be better off with a mouse. I tried using the "room" tool, but I found that it merges the sides of the room with the exterior walls, which are much thicker than the interior walls, and that seems to cause problems that I don't understand. So I just used the straight wall tool to construct each room. It merges those too, but without the issues that the room tool seems to cause.

That gets a bit exhausting after a while, so I had another conversation with the AI, asking about budget. I gave it our contractor quoted rate for the work he will do, and the portions of the build that we will be responsible for, and asked if it could estimate the cost of our portion of the work.

It commented that our contractor's rate was reasonable for the region, and then gave a low and high estimate for each of the areas we will be responsible for completing.

Using the midpoint estimate, we'd be busting our notional $500K budget by about $80K. That wasn't particularly shocking to me. Unfortunately, it doesn't include the driveway expansion and the new septic tank, which are together about another $17K; so, again, we're approaching that $600K mark. That's not entirely out of reach, but it is a significant stretch. I think it's achievable though.

I'm committed to ICF construction because of the weather we just experienced this weekend. We can anticipate more extreme weather, more severe extreme weather, in the years to come. For the purposes of my analysis, I'm assuming we'll have at least 15 years in the house, which should put me in my mid-eighties. Mitzi's mom lived well into her 90s, albeit with some form of dementia, and my mom will be 93 in September. Each of our fathers died younger, but my dad was 87 when he passed. So far, no dementia in my family, so I have to anticipate that I may be a caregiver for some time. Mitzi has long-term care insurance as well, so I think we're fairly well prepared in that regard. Of course, "People plan. God laughs."

But back to the house. ICF will withstand the most severe weather extremes. I'll have to talk to Brad about strapping the trusses down, I don't know if New York follows Florida's code. You can build an ICF roof, but that's even more money. So the roof will be the weak spot with regard to wind damage. In terms of extremes of heat and cold, the thermal mass of the concrete envelope acts as an enormous thermal shock absorber. If we had weeks of extreme heat or cold, that advantage might turn into a small disadvantage, but I think for the most part it's going to save us money on heating and cooling (mostly heating in Climate Zone 5).

We'll have standing metal seam roofing and siding, so no paint, no pests, burning embers shouldn't be a problem. ICF homes don't burn, per se. Apparently the EPS beneath the siding melts rather than burns, and of course the concrete isn't flammable. The biggest fire risk is interior, and beneath the eaves, so we'll want to keep flammable vegetation away from the house. You don't want fire entering from the eaves, and spreading into the roof.

I was wondering in the wee hours this morning how much of a Faraday cage the house represents. With metal roofing and siding, and all that rebar in the walls, how much of an EMP event would enter the house? Of course, everything plugged into the electrical system would be fried. And I'd have to think about whether or not the roofing and siding have to be grounded to be of any utility. Something to chat with an AI about.

But the important thing is, you don't want to find yourself homeless in your 70s and 80s, which is why we left Florida. Of course, no place is truly immune to climate disasters today, but I'm fairly confident the risks are more manageable here, especially if we build an ICF home. I listened to a podcast the other day, and apparently ICF is surging in California in the areas destroyed by wildfires. Likewise in Florida for hurricane destroyed homes.

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