Manual J Default Air Leakage Inputs vs. Blower Door Test ACH50

I'm pretty sure the awesome folks who created Manual J (like Hank Rutkowski- hear my interview with him here), and the softwares we use to run the calculations (Elite RHVAC, used here, and Wrightsoft) do not have a lot of personal experience with the test dynamics of home enclosures, and may never have actually used a blower door before. Here's a demonstration of why it's so important to respect the blower door if you're doing HVAC design for residential construction or home improvement.

Learn to perform and analyze Blower Door and Duct Tightness Tests in my 1 Day Training at: https://buildingperformanceworkshop.com/det-verifier

There are two blower door brands, both available at: https://www.trutechtools.com/system-blower-doors-and-duct-testers.html

See a tour of a full Manual J report below:

How to Hide HVAC Grilles and Replace Your A/C Faster

My friends, DO NOT DO THIS. Friends don't let friends put HVAC grilles, especially the central return grille, anywhere a couch might end up backing up against it. Ceilings, great. High wall, fine. Floor, not so great but probably better than this. Learn more about HVAC performance by subscribing to our channel and joining our Patreon membership: https://Patreon.com/HomeDiagnosisTV

Brilliant Basic Tools for Building Science: Psychrometric Wheel Calculator

To predict and prevent humidity problems, use a tool like this Psychrometric Wheel Calculator. Understand more about the relationship between tehmperature and relative humidity, absolute humidity, and dewpoint.

Join our Patreon members for as little as $5 a month: https://Patreon.com/HomeDiagnosisTV

You should be able to find one of these for sale (between $2 and $50): https://www.google.com/search?q=psychrometric+wheel+calculator

Legal Battle over a Mold House: Anil's Lawsuit against Production Home Builder & Lessons Learned

Hear advice and lessons learned from somebody who is willing to throw down with the (second) biggest homebuilder in the USA (as of 2022's numbers, they're slipping haha). Ryland Homes was sold and became Cal-Atlantic Homes, which in 2018 was sold to Lennar. Anil Mittal is a force to be reckoned with- here's how to be like him when you grow up.

See the tour of their mold-infested home, and get the analysis on the house itself here: https://youtu.be/x_jAxHZ-zLE

Get a DIY mold test kit if you think you need one: https://GotMold.com

How to Start a Mold Investigation Inexpensively: GOT MOLD? DIY Mold Test Kit

Our friend, longtime mold inspector Jason Earle has developed an affordable DIY kit for renters, teachers, and anyone else who'd like a quick and easy way to spot check for airborne mold. Here's his background with mold exposure from childhood, and what led him to R&D for this valuable monitoring solution. Check out the kits or order one: https://GotMold.com

How NOT to Pick HVAC Registers and Grilles: Aria Vents Test Data Reviewed

One of my HVAC design clients sent me a question about these vent covers he found online, and it cracked open the whole basket of eggs. Here's a brain dump on how to look up the performance data on products like this. Here's a brand of decorative grilles that perform well- I know because I test them: https://stellarairdecorativeventcovers.com/

Learn WAY more about HVAC on our playlist: https://www.youtube.com/playlist?list=PLsc2-5fAgMq5yJOp-kliEoYVML8dS1G2f

Join our Patreon group for exclusive access to us and our work behind the scenes: https://Patreon.com/HomeDiagnosisTV

Mold House Tour and Scientific Causes: Disaster Production Home Build in Houston Texas

Meet our friends Anil and Nilima Mittal- they're suing the biggest production home builder in the USA. With help from Jason Earle, 20-year mold inspection veteran, we tell the story of how this mold disaster of a brand new home began, and how their health has suffered because of it.

Get your own simple mold test: https://GotMold.com

Become supporters of our work, just like Anil, and join our Patreon group for as little as $5/month! https://Patreon.com/homediagnosistv

HERE’S A SEPARATE VIDEO WITH ANIL’S TIPS AND TRICKS ON THE LAWSUIT ALONE:

Toss Your Black Plastic Kitchen Cookware: It May Have Lead and Flame Retardants Built In

We talked with University of Toronto researcher Miriam Diamond, and she dropped this bomb. This is not a drill, or a joke. Researchers found LEAD and FLAME RETARDANTS leaching from black plastic cookware of all types, brands, and prices. You simply cannot know if they made it black to hide recycled content or not, and the plastic they use comes partly from recycled electronics- hence the chemicals. We hope you share this tidbit with everyone you know- the manufacturers too please.

Manual S Deep Dive: Selecting HVAC Equipment Based on Manual J Load Calcs- Part 2 of 2

Picking up where we left off in Part 1 (https://youtu.be/LEKEMI05dJE), Alex Meaney shows a design where a 3.5 ton, a 4 ton, and a 5 ton air conditioner all match a Manual J load, and explores the fine points of practical applications of the 3 rules of Manual S: 1. Select equipment that can handle 100% of the humidity load (latent heat) at minimum 2. Select equipment that does not exceed cooling load by too much (15% for single stage equip, 20% for 2-stage, 30% for variable capacity) 3. Select equipment that does not exceed total capacity by too much (but this rule must be broken in some cases)

Check out Alex Meaney's trainings: https://MeanHVAC.com

Watch Matt Risinger's video on the Build Show about my Manual J report tour: https://www.youtube.com/watch?v=CL-_VjlYnD0

Manual J Deep Dive (and Selecting HVAC Equipment with Manual S)- Part 1 of 2

Alex Meaney is my trainer when I level up on HVAC design calculations, and he came to visit us and share some of his expertise. Alex reveals what the J stands for and why you should never round up the tonnage from your Manual J software, and gives two rules for Manual S: 1. Never use AHRI data 2. Meet the latent load while not going too far over the sensible load (more in part 2) Check out Alex Meaney's trainings: https://MeanHVAC.com Watch Matt Risinger's video on the Build Show about my Manual J report tour: https://www.youtube.com/watch?v=CL-_VjlYnD0 Learn more about the Science of Homes: https://BuildingPerformanceWorkshop.com Watch the first-ever TV series about the Science of Homes: https://HomeDiagnosis.tv

Where Best to Put Ventilation Intakes? ERV, HRV, Supply and Intermittent Exhaust Vent Terminals

The maintenance of homes just doesn't stop, whether it's a high performance home or not. There are too many variables between family behaviors, between homes, between neighborhoods and climates that you just can't predict everything. Tweaks must be made. Here's a quick demonstration of HOW and WHY to clean the ERV or HRV outside ventilation terminals, as well as a quick modification of the insect screen on these 8" round duct hoods.

More on this home at: https://homediagnosis.tv/atlanta-homestead

Home Disasters & Resilience: SciPub Q&A on 'Home Diagnosis' Season 3

Join Grace and Corbett Lunsford, creators of 'Home Diagnosis' on PBS, at a SciPub live audience discussion led by Nancy Scales-Coddington about disasters and resilience in homes at Cornell University. Season 3 of the series is called 'Accidents Happen', and explores disasters both natural and human-made (like adding ozone generators, skipping air sealing, putting plastic vapor barriers in the wrong places), and dives into the science behind them in physics, chemistry, and microbiology. Learn more from WSKG's SciPub series at: https://www.youtube.com/playlist?list=PLkEiFS5w2pdm-95WA4ak2xXsFMxF2NWIm

Thanks again to Wise Home Energy's Jeff Flaherty who came out and demonstrated tools and answered questions for the crowd too: https://www.wisehomeenergy.com/

Learn more at: https://HomeDiagnosis.tv

Support the making of 'Home Diagnosis' and our YouTube channel for as little as $5/month at: https://Patreon.com/HomeDiagnosisTV