Thursday, September 29, 2022

Minimal Damage from Ian - Mostly PITA

Let me start out with the good stuff.  The weather predictions I talked about were very accurate.  I don't think we had even a gust to cat 1 hurricane level (75 mph) and "gusts don't count;" that definition of hurricane is one solid minute of straight line winds at that level.  We never lost power for a second.  While it was a windy, rainy 24 hours or so, there was little damage.  In fact, the only damage pretty much came from my believing the forecasts a bit too much and preparing too little, but more of that later. 

A widely known but rarely stated reality about tropical storms and hurricanes is what a pain in the ass they are.  Prep time (even if you don't have to get within a mile of store parking lot, like us), figuring out what level to prep to (cat 3 or 4 gets more attention than lower categories) and the inevitable PITA cleanup after the storm.  With losing our palm trees after our August of '19 lightning strike, and having our oak removed this June, you'd think I wouldn't have as much cleanup.  Not that I can tell.  I have half of my backyard neighbor's trees in my yard and and almost as much junk from my next door neighbor's trees.  And I only have those two neighbors, not three like many people do. 

The long story.  Since much earlier in the week, it was apparent we would not get Ian - at least, not as a hurricane.  Every prediction had it as a hurricane somewhere over on the west coast, initially (and finally!) coming ashore around Port Charlotte, then various places farther north on the west coast and at one point, coming ashore south of Tallahassee (the state capital) - followed by retracing those steps toward the south and back onshore the west coast of the state.  We were always looking at tropical storm winds.  

You might have gathered that I don't pay much attention to tropical storms.  (WARNING: Gross simplifications ahead)  Aside from a longer duration, they're really not terribly different from a thunderstorm.  A typical thunderstorm has winds from 30 to 50 mph, and a severe thunderstorm has winds over 55 mph.  A summer thunderstorm actually lasts about 20 minutes but as the thunderhead collapses, it can push air up and build another storm so that they seem longer but even then rarely last an hour.  A tropical storm has winds of 45 to 74 mph and can last hours upon hours.  

Since we have something like 80 to 100 hours of thunderstorm time every year (my guess) I have the opinion that my house and everything around here can handle tropical storm level threats.  I don't even notice when we get one.  So when the forecasts said a tropical storm was coming, I treated it like a thunderstorm.  I essentially said, "so what?" and did very little.  

Everything was going along just peachy until the NWS suddenly upped our tropical storm warning to a hurricane warning around 11 AM on Wednesday.  Even though our local forecasts were saying winds would reach 40 sustained to maybe 60 on gusts and the probability plots showed the chances of hurricane winds were about 35%, we decided to put up the shutters.  Unlike any other storm we've prepared for, we only did the north and east windows because that's the direction that other storms hit us the hardest from.  

Since much of that work was being done in the rain with more forecast, I thought the ham antennas would be fine and didn't plan to do my usual hurricane prep, which is to crank over the tower, pull the antennas and crank the tower back up.  When I walked around the house to the east side, I saw something that made my blood run cold. 

Back in the late '80s/early '90s, when I put up the tower, I did a DIY house bracket.  An electronics tech I was working with at the time did the welding for me of a couple pieces of angle iron.  In '16, when I did the replacement of the steel pole with aluminum, I drew up this view of the house bracket minus the house. 

The white parts are the angle iron, and the face on the right is up against the house.  It's bolted into the house's roof trusses with two 5/16" x 2" long lag bolts and the little red circle on the right is a rough idea of where one is.  The other is off the left end of this picture.

What terrified me was that I saw that bracket was pulled out of the roof trusses and the tower was just standing there, rocking slightly in the wind.  There were only two things I could think to do; either crank it over and leave it over through the worst of the storm (top end leaning on a ladder) or try to find bigger lag bolts to reattach it to the house.  I thought I had a couple of long - like maybe 6" - lag bolts but they've teleported themselves into another part of the multiverse. I had some slight larger lag bolts - 3/8 instead of 5/16 and much to my relief, they worked.   I thought everything was peachy.  

Today, everything got worse.  At about 8AM as I was doing a morning inspection, I found 1/2 of one element of my HF antenna, a log periodic beam, had broken off.  The break looked ragged, not clean, so it fractured.  I was alarmed but couldn't do anything other than note it.  Around lunch time, I went outside to look things over when there was a break in the rain, and everything was worse.  

The other half of that T6 element had broken off.  When I went around the side of the house I could see the house bracket had ripped out the new lag bolts and the tower was just swaying in the wind like yesterday.  Winds were in the vicinity of 40 gusting 65 at the airport, less than 3 miles from us.

So I cranked the tower over and it's now resting on the wooden ladder with the end of the T6 antenna about a foot above ground.  I didn't get a picture, but this is one originally from last winter when I replaced the top antenna - except I put red marks around the two halves of the element that broke off. The position of the tower and the ladder is almost exactly the same.  The oak tree in the background is long gone.

The antenna can probably be fixed by trimming back the very end of the broken off halves and reattaching them to the pieces of the element still in place.  That could change the element length slightly, but it shouldn't be significant.  The house bracket concerns me simply because I don't know why the lag bolts pulled out in the first place.  My gut feeling is to increase the size of the lag bolts again; either to 7/16 or 1/2" and make them longer so they go into (hopefully) virgin wood in the roof trusses.  

All that said, we're clearly in much better shape than the folks over where they got the Cat 4 Ian.  There's a world of difference between the storm they got and what hit us.  We never lost power, we didn't lose any roof shingles, and the only damage at all is this antenna and tower.  The only unknown I have is that my backyard neighbor's tree grew over the roof of the shop and I was concerned the branches rubbing on the shingles would damage the roof.  It turns out that those branches broke off and are lying between the fence and the back of that part of the house.  I can't see the shingles to make sure they're good and can't get a ladder up in that area until I cut down the branches. 



24 comments:

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  3. $=#@%_&<@@! Autocomplete !!!

    I doubt if longer lags will help. The trusses are probably only 1 1/2 thick, 3 inches if they are doubled on the end of the house. I am thinking that the real solution besides using the larger diameter lags on the existing bracket is to add some supplemental brackets, if possible, to share the load under stresses like the storm winds.

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    1. Interesting thought, but I can't think of what that would look like.

      It would help to take a look in there and see what it looks like but that's something that should be done either on the coldest day of the year or in an air conditioned astronaut's suit.

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  4. Get some threaded rod and go through at least 2 trusses and use a backer plate on the furthest truss.

    Make the plate that goes on the outside eave much longer and use at least 4 threaded rods. Spread the load over more surface area and deeper into your roof.

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    1. Meant to say that this is what the satellite dish installers did when pinning the pole for the dish to the roof, back in the days of 12' sat dishes. 20' pole for said dish because yard was very wooded. So installers went through several rafters and used lots of plates on either side of rafters and very long threaded rods and and and...

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  5. Glad you made it through with only that damage. It is repairable.

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    1. Didn't realize I was an Anonymous.

      BillB

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  6. I'm glad you're ok. Thanks for posting that.

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  7. Agree with Beans. Use through-bolts, with fronting and backing plates to spread the force out more. Most people I've seen do this also "double up" with additional thickness added to the trusses.

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  8. Since the code changes for how decks and deck railings get built, a whole bunch of really clever/neat/well engineered metal hardware has been invented to spread out the load and strengthen connections. Some of that hardware could probably be used on the truss side of the connection too. Simpson StrongTie (tm) is the most common, and available at Lowe's and Home Depot.

    Glad you made it thru without any major issues.

    nick

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  9. Beans is right, but it would be the Bentley way to do it when a Ford way would do. My experience with lag bolts in decks tells me that your originals were WAY too small and WAY too short (a Yugo way). If you are only relying on two bolts to hold against the really significant side force, you should have used 1/2 inch bolts at least five inches long. Make sure to use pilot holes of the diameter of the bottom of the thread minus ten thou or so, otherwise the wood will split and give you zero strength.

    The problem with smaller lagbolts isn't their diameter, but the thread depth. There's not enough grip into the wood. Imagine tapping and screwing an 8-32 bolt into wood. It would hold fine in shear (say, holding a sign) but it would pull right out.

    Also, I would have put a T on the end of the cross angle so that two bolts per truss could have been used. Hindsight is 20/10, of course. Good luck with the PITA. You'll get to do it again for the next hurricane ;0

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    1. My biggest problem is not knowing exactly what it looks like in there. When I put it up, I didn't have a stud finder but somehow found the two trusses. I also would have sworn I used longer bolts. I don't really know what it's tied into, when I say "trusses" that' s essentially PFA, I just know that it has been there since I put up the tower in '90. Within a couple of years, we had a Cat 1 hurricane while I was on a biz trip and my wife had no idea how to take it down so it stayed up and was fine. I've taken it down for every hurricane since.

      I'm playing with the idea of whether or not I could fly a drone in the crawl space and take video of the area. It is seriously hot in a crawl space, especially this time of year. Life-threatening hot, and the area I have to look out is as far from the access to attic as one can get in the house. I'm not the guy to do that.

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    2. You won't be able to get down to that space, with a drone, or on your stomach, "because insulation". Been there, tried that, cursed my stupidity for weeks afterward. What you can do is drill several holes in the soffit or fascia and use a cheap borescope. You'd have to patch the holes with a bit of caulk afterwards, but the information might be useful.

      Also, a thermal camera will give you a very good idea where the truss ends are, if you catch the right time of day.

      When I built my house, I used 2x8 fascia instead of 1x8, so I just bolted the bracket right to it without worrying about truss ends.

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    3. I have had to access the top of walls that I couldn't get to from inside the attic, either because the roof and ceiling had weird levels, or because the attic space was too low for me. I have had great success by just cutting another soffit vent into the soffit, and after I'm done, cover it with a vent to match the rest of the house. If you have perforated sheathing instead of metal grills, one metal grill painted to match won't look out of place. And if you have sealed soffits, just close the hole, then put the metal grill over it. The grill will hide your butchery....

      n

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    4. Interesting idea, Nick. In the decades since we put up the tower, we covered the soffits with aluminum, so there are no nearby vents to get in there. A borescope shoved through an inch or so diameter hole seems like the most promising idea. I don't have one, but that's not a show stopper.

      As of now (Sunday) this is looking like a short term fix to get the tower and antenna out of the yard followed by a longer term fix to make it stronger "when it cools off" in a month or two. The short term fix is looking like 1/2 x 3" lag bolts. Unless the wood is so weakened that those don't work, but I don't think I can know that until I do it.

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  10. I'm just damn glad you weren't in Fort Meyers!!

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    1. Me, too. I've only been there once or twice on vacation trips around the state. Nice place, but I never had the urge to change coasts.

      The never ending hype cycle from the weather forecasters is bad but still may not capture as much of how bad as being there. That was truly epic destruction. The thing that's never mentioned is that those landfall events are pretty localized. We all hate to think this, but sometimes survival does come down to dumb luck.

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  11. Make a new bracket from steel and ancher it into the concrete block wall. I’ve been there before with lag bolts into fascia boards. Over time with cyclic loading the wood yields. Undetected wood rot adds to the failure mode I had a similar set up with a 25 ft homade lattice tower topped with a Cushcraft A3S. The tower was anchored into a concrete base and bracked into the wood fascia at roof level with wood lags, just as your installation. It lasted about 7 years. I fabbed a new bracket from steel angle that I anchored into the block with 5 ea 1/4 in Tapcons. Unistrut could be used if welding not an option, but that stuff is priced like gold today. Might I ask the make of the log periodic ?

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    1. The LP is a Tennadyne T6. The last several times I'd been to their website I came away thinking they didn't make it anymore, but it was on there yesterday. Granted, twice what I paid (as if I remember) but that was around 2004 (I don't even remember that).

      BTW, it replaced an A3S, and I did that tradeoff to get a better antenna for 17 and 12m than the 40meter off-center fed dipole I was using.

      Re: your other topic: that's a good idea. It might just be the way I go. My tower is a 20' tall Aluma tower, and they used to sell a mounting pole that would handle their 55' tall, dual section towers. I'm thinking it was either the same diameter as the aluminum pipe I crank mine over with - 4" - but now I'm not sure. A taller, crank-up and tilt-over tower has been my dream forever. That's also about twice the price it was the last time I looked.

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  12. No significant tree problems up here in PSJ. Just usual palm frond litter. Power was fine until just after 8 PM on Thursday, when our transformer let out the magic smoke and auditioned for the War of 1812 Overture. Florida Flicker and Flash says they should have it back on by midnight Sunday. There were trucks on the street yesterday, but not tasked to our outage. Fortunately Home Despot had generators in stock, and I was able to get gas so I think I haven't lost anything in the fridge.

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    1. For those not familiar, PSJ pretty much got the eyewall - the worst part of a storm. A royal PITA, but not surprised you'd lose a transformer.

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    2. Almost 24 hours AFTER the storm passed!

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  13. Here in Arizona, I'd never use lag bolts, wood dries out and loses holding power. Lags into end grain are strictly temporary. Perhaps spread the load using angle iron 6-8 ft. across.

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