Anchoring With “J” Hooks

Typical “J” concrete anchor

Recently I have been asked questions about anchoring manufactured homes using “J” Hooks (or “J” concrete anchors) that are wet set in the concrete footings. While I am not an engineer, let me share with you a few practical things that I learned over the years about anchoring and what you should consider if you want to use “J” type concrete anchors.

Incorrect vertical strap from “J” anchor to beam

A quick look at an installation manual shows that in Wind Zone 1, we need to anchor the home with diagonal straps attached from the chassis beam to  ground anchors placed just inside the skirting line of the home.  In Wind Zone 2 and 3 we need both diagonal and vertical straps. In every case, diagonal straps are needed. Diagonal straps secure the home from sliding and up-lift in the event of windstorm. If the home is anchored only with vertical straps from the footing to the main beam, they might prevent up-lift, but not sliding of the home.

 

Angle finder showing 75°-Too steep!

Most installation manuals require a maximum strap angle of 60° from horizontal. Installing “J” anchors in the footing generally result in a strap angle of around 90° .  An inexpensive ($5 to $10)  angle finder is a valuable tool to make sure you have the proper strap angle. Snap a picture for your installer file.

 When I look over the actual instructions for proper use of the “J” anchor, it is obvious that these anchors are designed for concrete slab design, not to be placed in individual footings. This is based on the fact that each “J” anchor must withstand 4725 lbs. of tension without lifting. Assuming one cubic yard of concrete weighs about 4,000 lbs., you can see that you would need close to 1 ¼ yards of concrete per footing to properly hold the “J” anchor. A typical 24” diameter x 36” deep footing takes roughly 1/3 of a yard of concrete. Not even close to the amount needed to reach the required holding capacity of 4725.   

Slab design with “J” anchor at side wall

So, where does this leave us? If we are placing a manufactured home on a frost protected concrete slab, the “J” concrete anchor might be the answer. Place them a minimum of 4” to a maximum of 10” from the edge of the slab, and keep an eye on the strap angle! The thickness of slab should be 2” greater than the “J” length where it is embedded in the concrete. So, a 6” “J” anchor should be embedded in 8” of concrete.  But as always, you need to do your homework and make certain you are anchoring every home consistent with the home manufacturers installation manual and using the anchor components as they were designed!

My advice is to look at the newer anchoring systems that are available on the market today. Most of the home manufacturers have reviewed and approved them to properly anchor their homes. While they may be a little more expensive, they are certainly less labor intensive than other anchoring techniques, especially when you factor in end wall anchors. As always, talk to the home manufacturer. The anchor producers all have a lot of good information on their web sites and they all have some great technical folks on staff who are always available to answer any questions. So, give them a call before you start your next job!

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Would You Like That Super Sized?

Have you noticed that with almost everything you buy, you’re given the chance to enhance your purchase? You can add on a protection plan, increase the size, quality, or quantity on almost everything. Often the choice is centered around an opportunity to improve customer service, or to offer an upgrade beyond the manufacturer’s minimum requirements.  When the oil change shop checks your  tail lights, turn signals, or windshield wipers, isn’t it perceived as good customer service?  Many HVAC businesses offer annual service contracts as an improved customer service option. Evidently, some pretty enterprising folks have found a new way to profit by giving their customers choices, and maintaining relationships beyond the initial sale.

Ok, I understand financing is tough and money is tight, but let’s consider a few simple things that might lead you to increase your bottom line. Just as important, these ideas can improve the overall performance of the homes you install.

Marriage line gasket options:  The conventional gasket is fine, but imagine the savings in heating/cooling costs if you offer your customers an “Energy Upgrade”. Maybe a double gasket? Or maybe you spray foam along the marriage line that would eliminate all those little air leaks that cost the homeowners money and impact their comfort. Think about it as the “Good, Better, Best” approach. Given the choice, many of your customers may opt for an “Energy Upgrade” and be very willing to pay for it!

Foundation options:  Would some of your customers be willing to pay for a heavier foundation if giving the choice? Maybe a foundation designed for a 30 lbs. roof load even though you only need 20 lbs. foundation.  Or maybe a 40 lbs. foundation for a 30 lbs. area? Several manufacturers overbuild their homes to achieve a more structural substantial home. Why don’t installers/retailers consider offering similar choices?

Anchoring (or stabilizing) options:  You could offer the conventional ground anchor and straps, or an upgrade to one of the more modern, high tech, steel bracing systems. Give your customers a choice!

Right now you are probably thinking, these ideas are geared more towards retailers at the initial sale, and that is true.  But what about some after market opportunities?

I think a lot of our customers would be willing to pay to have a professional installer visit their home once a year and perform an annual foundation inspection. Inspect the support piers for cracked blocks, or loose shims. Check the tension on the anchor straps. Examine the bottom board for holes, and while you are at it, look over the ground vapor barrier. Are the downspout elbows, leaders and splash blocks still in place? Is the heat duct crossover still air tight? Look over the roof shingles and check the flashing and other penetrations. And while you are there, test the GFCI, smoke alarms and check the dryer vent!

The “Complete Installation Checklist” that you already use to confirm the installation is correct, can be exactly the tool you need to make clear what you would inspect, and how to document your findings. See my post “A Very Valuable Tool” from January 6, 2017.

I am certain many of your customers would love to have piece of mind that their home will continue to deliver the quality, durability, affordability and safety that manufactured housing is all about!  And maybe the person to deliver that piece of mind is you!

A Week Worth of Inspections!

Through my career, I have inspected hundreds of manufactured home installations, but not too many as of late. That is why I jumped at the chance to travel west and look over 10 recently installed manufactured homes. I wanted to share what I learned with all of you.

Over the course of the week, I had the opportunity to meet with several installers, retailers and other industry representatives. Their knowledge and professionalism was impressive! They were proud of their installations, quick to answer questions, and eager to see if there was any information that I could share with them. These folks represent the industry well as evidenced by their work.  

Next were the homeowners. While only about half were home during my visits, when given the chance to talk about their homes, they had nothing but good things to say. They love their homes and they were sure willing to talk about it!

Also impressive were many of the installation techniques I observed.

 Most homes used some type of anchor and strap tie down system. I was pleasantly surprised to see that almost every home had strap protection where the straps wrapped around the main beams.  

The concrete work was very well done. The concrete footings were smooth and level, providing a great surface for piers.

Multi-section homes were well finished, joints were tight, trim and drywall were first rate, in fact it was difficult to find the mate line once you were inside the homes.

Ok, but what about areas needing a little improvement?

Site grading. It was easy to see where the term “flatlander” comes from. Most sites were completely flat. And since the sites are so flat, little or no excavation is needed. I suggest that a couple loads of fill dirt be included with every job to achieve that “turtle back” effect that is needed to get the water to flow away from all four sides of the home.

Pier construction. Overall the piers were great, with a few small concerns.  Several homes used ¾” thick 8” x 16” wood or 1″ concrete cap blocks or spacers on-top of the cap blocks. Most Manufacturers Installation Manuals require nominal 2” x 8” x 16” lumber or 2” or 4” concrete for cap blocks and 2” lumber or concrete spacers. Check your installation manual to make sure you are using the proper cap and spacer material.  

On that same note, I noticed some undersized hardwood shims. Again, don’t trust me, check your manual, but 4” wide x 6” long is what most require.

Dryer venting. I saw a few crushed ducts, and one duct that was blocked by the first course of siding.  I also ran across a few folks using the foil duct material. See my post  Clothes Dryers- What Every Installer Must Know! for more information on this topic.

It was a very wet and busy week, topped off by a cancelled flight and an all-night drive to get home.  But I am extremely fortunate to have had the chance to meet and work with such professional manufactured home installers, retailers and representatives. I hope to get the chance to work with all of them again soon.

Difficulties With Porches

A few years ago, I was called upon to investigate a complaint filed by a homeowner in a very high end, 55 and older community. The complaint was generated because the homeowner believed that there was mold growing in the crawl space under her home and she was hyper sensitive to air born mold spores.

To paint a better picture, these were all two section homes installed on a masonry (block) crawlspace, on frost protected concrete slabs that were poured 3’ below the surrounding grade.

Once backfilled, the slab will be below the frost line.

The crawl space was properly moisture proofed and the sites were well graded for proper drainage. But the inside of the crawl space was soaking wet even on the nice summer day when I visited.

Notice the wet blocks under the porch area

And sure enough, you could see mold and mildew on the bottom board and in the floor cavity where the access panels were not replaced. The homeowner had a legitimate gripe.

 

As you know, water is needed to support the growth of mold, so we just needed to find the source of the water. The water source was easy to find. The lawn sprinklers!

Every evening, the automatic lawn sprinklers would slightly overspray the grass and water was landing on the recessed porch decking on the end of the home. The porch was decked with composite material that was installed with just enough of a gap for the water to pass through and collect in the crawl space. The ultimate problem was that the crawl space was constructed around the outside of the porch, instead of just around the living area of the home. So, with every lawn sprinkle, rain or snow that landed water on the decking, water was being introduced into the crawl space.

So, I decided to see what the manufacturers installation instructions say about recessed porches. Most installation manuals have two sentences dedicated to this topic, back somewhere around page 95 of most manuals: “Run the skirting along the perimeter of the homes heated, conditioned space. Do not enclose with skirting areas under recessed entries, porches or decks unless the skirting is of the fully vented type and installed as to allow water to freely flow out from under the home”.  And to complicate matters even further, the ground vapor retarder is not to extend under “recessed entries, decks or porches”.

It would be difficult for an installer is to design a crawl space enclosure-skirting that “allows water to freely flow out from under the home”.

Home sits in a “pit” No way for water to escape.

And even if you did, the homeowner would likely do some landscaping that might act as a dam and trap the water in the crawlspace. Easy to see in these two pictures that any water landing on the decking is going straight into the crawl space.

Water gets captured inside skirting.

 

As we are seeing more homes being constructed with these decked porches we need to take a harder look at this issue. Running skirting underneath the home is difficult at best. I have run across one example that is well done. In the picture below you can see the porch area is only enclosed with a vinyl lattice that allows any water to escape. And yes, there is a crawlspace wall (skirting) under that front end wall.

Crawlspace under front end wall, behind lattice work.

 

Maybe some manufacturers have a better idea. But don’t take my word for it, grab an installation manual, turn to the section Complete Exterior Work- Install Skirting. Let me know what you think.