Structural Connection Design for the Home Inspector. New advanced article.

Structural Connection Design for the Home Inspector.

Nice, thanks

Very good info, thanks!

We’ve been putting out advanced articles because there is a subset of our membership that wants to drill deep on subject matters.

Good article.

I assume inspectors are to use the bolt equation for ledger board connections, but this is not part of the article? Can you clarify? Should it be used for inspections?

Also, can you explain how a “typical” home inspector can a) understand the Engineering Physics required to use this article and b) do a “code” inspection?

This is a great resource for technically trained individuals but would be difficult for those with a minimal math background (in my opinion). I believe inspectors require this kind of “knowledge” in order to properly inspect a structure (like a deck for example) and feel that more training is required for this level to be used effectively in a “visual” inspection.

I do structural inspections and rarely use math more complicated than addition. You don’t really need to understand Engineering Physics to use this article, you just need to understand concepts and connections. The heavy math explains how they arrived at the conclusion that, for example, “the minimum anchor bolt spacing for mud sills of a shear wall in California is 4’ OC, and anchor bolts must be installed within 9 inches of the ends of each mud sill”. When I do a structural inspection and see Anchor bolts 8’ OC I know it does not meet minimum design requirements, but i don’t need to know the math behind it.

I think this article is good for the average inspector because it explains the basics of load transfer that would be considered a minimum standard in most states, and spending the time learning the basic load transfer techniques for the conditions typically seen in your area will make you a better visual inspector.

Math equations are for Engineers and Architects, Home Inspectors need just the basic fundamentals of the structural connections as shown in that articile.
Some field experience helps.

Like maybe the picture should of been of a pressure treated lumber with a galvanized anchor bolt, just to be on a professional side. ;)COLOR]

How so? How would you use that article to inspect a newly built deck? How can you determine if the ledger bolt spacing is Ok especially since you are doing a visual inspection and have no way of knowing what is behind the ledger? Does the bolt spacing not have something to do with the following a) species of band joist, b) penetration of the fastener (4D, or 8D), c) the wet service factor for the design, d) the loading on the deck (DL + LL), e) if a hot tub is on the deck, etc…etc…etc…?? So how can this article help you? The Engineering Physics would be a heavy factor in understanding “why” the factors I just mentioned would be important. This is why I mentioned it in the first place. The math is required to “verify” if the fastener meets the situation “for that deck”. Since you are doing a visual inspection you could not use a standard table due to the items mentioned. What do you think?? How does load transfer techniques help you assess a deck that “looks OK”?

Thank you for your observations and questions. We may be coming at this thing from 2 different directions. You seem to have a good grasp of the subject matter, i’m just a little confused why you don’t believe it will help home inspectors. I’ve responded inside the quote with caps to make it easier to read.

I was curious about who you are, I haven’t spent a lot of time in the forums. I see you are listed as a vendor. Do you sell things to Home Inspectors, InterNACHI?


Thank you for making it easy to read.
I too don’t spend much time with forums.

What would you use to ensure your visual inspection of the bolt distance is correct? Please explain. Also, how to you determine if you have 4D or 8D penetration of the fasteners? What if bolts are 3/8 inch lags? What is the “max” load a 1/2 inch and 3/8 inch bolt can hold?

I ask these questions because a home inspector must be able to advise if they require a professional to look at the ledger? How can you tell?

A hot tub is used by many and the home owner would not know that a problem may arise so again how would you know the hot tub does not overstress the bolt connection? Also, what specifically in the deck course addressed this vital connection? Please explain. What safety factor was mentioned for ledger bolts in this course?

I have a series of eBooks I wrote to be LOW cost and affordable to be used by university and college students. My eBook Engineering Physics series and Land Navigation series seem to sell very well. The profit margin is very low on these eBooks, so they were not written for the profit, but rather to help students and inspectors like yourself. I am finishing an eBook called “Deck Check” that will aid in the issues I was asking you about.

Decks are a** HUGE** problem and kill many people each year. Over half of the “new” decks constructed look GREAT, but are improperly constructed and attached poorly at the ledger. A deck is a structure - like a house structure. Unfortunately looking at tables or equations will not enlighten the reader without an understanding of the Engineering Physics and non concurrent forces on the members. Can you explain the load transfer on the ledger if you are not sure of the factors mentioned originally? How did you deck course address this? Everything is always great until a problem arises.

My eBooks would only benefit those home inspectors who want to go beyond the “obvious” defects to understand how the structure works (in this case a deck). This is why I presented them. My Land Navigation series is doing quite well and again to help those that like to venture in the wilderness. Many do not realize the limitations of a GPS system, so I wrote these to help them master the use of the compass and topographic map as it will save their life when used correctly.

My Construction estimation series has helped those wishing to “understand” the construction of a deck and know how to price it so that they are not taken for a ride by the contractor. Many decks are way overpriced. So this series helps home owners and maybe even inspectors who are planning to build a deck.

I do not sell things directly to inspectors. My eBooks are on and anyone interested can purchase them. I wrote these basically because I was asked by many why this info was not readily available in a “step by step” format where multiple methods were discussed. As you realize many hard covered technical texts are expensive, so this prompted the series.

You may be interested in this You Tube case I was given that may help you understand WHY I present the case I did.

I someone is injured or dies due to you lack of understanding of what a defect is or how to spot one then only you can be to blame. Those people inspecting decks (for example) residential, or commercial have a responsibility to the client. If you cannot tell if the ledger is at fault, then you have a problem if something should happen.

Bolt tables or equations are not adequate in judging bolt spacing on a commercial deck for example. Without an understanding of the Engineering Physics and Math you would not be able to understand how to inspect this type of ledger connection.

How does this article presented help those involved with commercial decks? How can the inspector understand how the loads are used on the structure, etc?