People often believe that diying "licensed" subtrades invalidates homeowner's insurance. Let's explore all the ways in which this is false. Comments are specific to single family homes within the US

I'm somewhat sympathetic to this mistake but thought it was interesting. Client had their copper water service replaced with PEX after it broke. The stranded wires are the original electric service ground, which probably became ineffective with the pipe upgrade. Moderately dangerous

Back on my home inspection report grind

Update: the heat exchanger wasn't cracked

A lot of people often seem to lose track of the whole 'buildings as a separation from undesirable stuff outside' thing. The central tenet is creating good conditions for people inside them. We can solve building related environmental and social problems afterwards

In 2015 my neighbor hired a guy to redo a bunch of concrete flatwork but he didn't know how to build stairs so I did them for her while she looked after my kids. The contractor berated me about my formwork because he thought it would have been better to stack boxes on top of each other

2012. The housing market was still pretty bad. I wasn't sure that I wanted to go all in on energy retrofits but the subs were pissing me off so I bought a $3k blowing and mounted inside a trailer. We'd drop cellulose at the house and have a really long day

Stop what you're doing and listen to Stephen Wilson Jr one take this amazing love performance. Just puts out everything!!! www.instagram.com/reel/DTN73PM...

Imagine dressing like the biggest larper imaginable but lacking sufficient skills to take down weakly resisting middle-aged women

I think of building thermal qualities and heat pump output as similar to the traditional economic supply and demand chart. Fossil fuel appliances are simpler because they have constant output irrespective of outdoor temperature

In the many years I've fought cracked furnace heat exchanger scams I've never once gotten out of an in-person service call. An owner just sent me this pic of the burners on his furnace after being told the 5 year old system will poison his family

Staggering! It looks like Nestle is potentially responsible for the deaths of 10 million infants via the promotion of baby formula in countries without clean drinking water. The boycott was a big deal when I was a kid, but NBER published a study on it in 2018

On the subject of windows everyone might be sleeping on motorized exterior blinds. I'm still testing the ones I installed at my place a year ago but they're definitely operationally better than anything else. Reliability is great so far but we'll see

The American window market is completely dominated by garbage but still expensive. It goes against my libertarian sensibilities but it's possible that if the big three window manufacturers disappeared overnight on average people's lives would be better

Troubleshooting a cigar lounge ventilation system and variable refrigerant heating and cooling. Finding really dumb 'fixes' everywhere I look. Probably too esoteric to do a full explanation but 2 of 3 heat/AC units here were broken for several years

Is it too mean-spirited to do a "what's your phd?" thread of pics Princeton professors have sent me that betray a children's understanding of buildings?

Troubleshooting ERVs today

Interesting video showing semi-trad Japanese framing. Project is 5 months but tbf this would be a decent timeline for a US project that encompasses framing, insulation, int & ext finishes. Seems to be a lot of overlapping modern materials with traditional techniques youtu.be/vRn8Ck2xiqo?...

Maybe in 2026 I'll stop running away from my problems

An obvious opportunity for prefab finishes would be pre-assembling of standing trim, but afaik this has little-to-no adoption. Average material thickness would have to increase, but there's a precedent with Jack-mitered trim, which is one of the sharpest profiles

I'm skeptical of anyone making claims about building tightness who doesn't post a pic of a manometer and it's pretty shocking this isn't a strongly entrenched norm. My skepticism increases with every formula added (cfm/sq ft, ach, naturalized leakage, etc) Single day 38% leak reduction

Many people - including HVAC techs - have a mental model where furnaces, boilers and water heaters lose a sizable fraction of their efficiency over time. In reality most appliances are either operating within ~2% of their nameplate or they're broken

Anyone can use my spreadsheet for sizing replacement HVAC systems using historic fuel billing data and it's way more accurate than having an HVAC contractor do a manual J docs.google.com/spreadsheets...

2 stage cooling is only available in even ton increments and premium modulating equipment is usually de facto 2 ton. What does this mean? 2 stage equipment starts at ~2/3 of capacity so eg a 3 ton unit starts at 2 tons and goes to 3 tons after 10 minutes or so

Wasn't familiar with the technical side of the Grenfell tower fire but this is pretty damning. The 2015 retrofit used a 6" foam panel with a 2" (!) vented rainscreen. The insulation would have been nearly worthless and vented rainscreens widely understood to increase fire risk

Piping for two furnaces. Each pair of pipes could have been consolidated into a single, more attractive concentric kit. The piping here was less expensive for the HVAC installer, but cost more in total due to the additional roofing expense

Here's a video that I believe to be a demonstration of the most advanced robotic system that's currently deployed. Putting aside the very weird and highly conductive plate stack, it's impressive only to those who have never seen production framing! youtu.be/O3al52UWoc0?...

Prefab would take off if we had uniform building regulations vs a regional hodge-podge which clearly gives the advantage to local specialists. And I mean local specialists like Weyerhauser which sells engineered products nationally through a hodge-podge of regional regs

I hold two seemingly contradictory views on prefab buildings 1) Aside from manufactured housing, prefab continues to be a total dead end in North America, as it has been since its inception

People can often use bathroom fans as supplemental ventilation to dilute pollutants. This is because for every cubic foot of air leaving via exhaust a cubic foot is pulled in via leakage

Bad duct practices explained to you by a male model

While we're probably well on the way to fixing the pre-registration problem in clinical trials, it's worth remembering that the majority of research on supplements is still of the 'heads I win, tails you lose' variety

Energy audits are a significant obstacle to building improvements and shouldn't be mandated by rebate programs. I'm not aware of any evidence that they improve outcomes, and auditors generally make prescriptive recommendations anyway. Just the dumbest nonsense

What's the longest you've milked a joke? My brother went on a road trip with his HS friends 30 years ago and one of them packed banana bread. They all still use "Joel's mom's banana bread" as a reference point for the driest something can possibly be

People often make annoying rebound effect claims where they suggest that offsetting energy savings with higher consumption is somehow bad. This feels completely backwards. It feels more likely that energy reducing technologies are critical to improved human living standards

People think doors and windows are responsible for a loads of air leakage but they're not. How do I know? Because we've systematically measured leakage in almost every building we improved for the past 15 years

There's no better example of a blue state shooting itself in the foot with petty and excessive administration than NJ municipalities requiring a zoning permit for a replacement AC or heat pump outdoor unit. Here's why!

Testing which terminals on this relay close using 12v DC power from my truck looks like something from bad idea jeans

Just trying to get a conversation started

I also condemn whoever this is. Also happy to meet with them and kick them out or whatever

I haven't heard this discussed but the way I graphically show heating a house with an air source heat pump is basically the econ 101 supply and demand graph

Taken from a Swiss prefab plant. Not sure if this is common but it seems odd that this isn't substantially better tech than a pneumatic stapler that's common to job sites. The main efficiency gain appears to be waist-high tables

My kids' school had an overnight "fire alarm". It's somewhat more likely to be a CO/smoke detector that's correctly triggering on CO. Things I'd check 1) natural draft boiler or water heater, possibly coming out of thermostatic setback not drafting due to cold flue piping.

One of the reasons I think HVAC is dominated by incompetence vs just greed is because people often can't buy their way into higher performance. So extremely high-end houses end up with some of the worst performance as their systems become increasingly complex

First crepe attempt on the truck kitchen

It's mystifying that in the post WW2 era the US and Canada rapidly embraced radically new building techniques. Apparently there are weaker European versions, (eg German prefab) but these don't appear to rival the NA changes despite portions of Europe being substantially destroyed

Here's a list of things people should generally forego in favor of improving building thermal characteristics. Zoning an HVAC system, humidifiers, dedicated room duct returns, two stage AC (cold climate), ≥18 seer ac (split not minisplit), hydronic distribution

Something that gets a fair amount of attention is people getting stuck in ideological ruts, usually related to politics, that derail them for years or decades. Yet this is also prevalent in engineering and technical domains, often with equally tragic results 1/2

If you can use your fossil fuel billing history to size a replacement heating system more accurately than using design software docs.google.com/spreadsheets...

People often approach solved technical problems as though they're an expression of personal preference without a correct answer. Very few residential bathrooms have a toilet paper holder in the correct location