New Decking, at Least
#21
  Re: RE: New Decking, at Least by hbmcc ([quote='Snipe Hunter...)
(07-17-2019, 07:26 PM)hbmcc Wrote: That's why the code displays utter stupidity when it prescribes notching for beams. Preservative chemicals may penetrate pressure treated wood a half-inch. Rot and bugs will show you where protection ends. 4.5 inches (6x6) will be destroyed just as fast as a 4x4 (2.5"). This is the exterior deck code I refer to.

I've inspected hundreds of decks and have never seen that.
 
"My mortgage self-identifies as a student loan."
... Kizar Sozay


Neil Summers Home Inspections
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#22
  Re: New Decking, at Least by hbmcc (About three/four yea...)
Onward to a not so simple redecking.....

The weather here has been crappy with typical western WA rain, everything is damp, maybe wet. Great cool temps however, so I am trying to do the designed demolition that accommodates aging vertigo and bad knees. Drudgery. 

Once enough old deck is removed the perimeter will be blocked for new bias-laid decking ends to be attached, allowing open gaps beside a continuous wrap of 5/4 x 6 edge band. The first lap of bevel siding will be damp proofed better. Then, all the horizontal surfaces will be taped with VYCOR protection. I am anxious to see how the diagonal laid decking will look, and expect to follow the demolition with new construction.


Next, some visible changes.....

Ps. Through all this project, the gutted deck needs to be constantly barricaded against a deaf, blind, and senile dog hunting for his summer cherry tomatoes--that won't be there. I think his smell is diminished, too.
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#23
  Re: New Decking, at Least by hbmcc (About three/four yea...)
    I couldn't wait. Cleared a space and loose-laid some 8-foot decking I had in order to test the "spring" a 19-inch span will produce. When the deck was built, codes allowed .75" cedar at 16" spans. It was springy even then. A full 1" thick board (5/4) is considerably stronger but the weakest boards will spring at 16" O.C.. Some of the test boards bounced more than I wanted.

That spacing and a 45-degree angle is not satisfactory. Strength and elasticity of cedar is dependent on growing conditions. The weakest board is from a fast growing juvenile tree, like the left side piece. Bouncy. Most decking, and common lumber, is now from young farmed wood stands. A board from a drier source, like the one at right, is stiff and has no problem spanning the distance. 

Spring is good. Just step into your workshop and compare concrete to wood. Too much spring is disconcerting. The weakest deck board determines the allowable joist span. My tests confirmed the code standards. I need to keep the intermediate (filler) joists and enhance their stiffness with blocking. Drat!
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#24
  Re: RE: New Decking, at Least by hbmcc ([attachment=19587]I ...)
(07-24-2019, 11:26 AM)hbmcc Wrote: I couldn't wait. Cleared a space and loose-laid some 8-foot decking I had in order to test the "spring" a 19-inch span will produce. When the deck was built, codes allowed .75" cedar at 16" spans. It was springy even then. A full 1" thick board (5/4) is considerably stronger but the weakest boards will spring at 16" O.C.. Some of the test boards bounced more than I wanted.

That spacing and a 45-degree angle is not satisfactory. Strength and elasticity of cedar is dependent on growing conditions. The weakest board is from a fast growing juvenile tree, like the left side piece. Bouncy. Most decking, and common lumber, is now from young farmed wood stands. A board from a drier source, like the one at right, is stiff and has no problem spanning the distance. 

Spring is good. Just step into your workshop and compare concrete to wood. Too much spring is disconcerting. The weakest deck board determines the allowable joist span. My tests confirmed the code standards. I need to keep the intermediate (filler) joists and enhance their stiffness with blocking. Drat!

Just a quick thought, from a simple minded individual...
What if you were to "sister" 2x4's along the top of each of the existing joists (1 ea side)? Would this not effectively reduce the span of each deck board? 
Seems like it might be faster than installing intermediate joists...
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#25
  Re: RE: New Decking, at Least by brianwelch ([quote='hbmcc' pid='...)
(07-24-2019, 11:46 AM)brianwelch Wrote: Just a quick thought, from a simple minded individual...
What if you were to "sister" 2x4's along the top of each of the existing joists (1 ea side)? Would this not effectively reduce the span of each deck board? 
Seems like it might be faster than installing intermediate joists...

That is an option, and simple too, but not in the mindless way. However, the remaining joists do have 2x intermediate support and spacing is 8". The intermediates need to be blocked every couple feet to be a rigid support. I just don't like all the mess of wood below. Birds nest in the pockets and it gets dirty. Mostly, moss algae, and lichens build up quickly here--I had to power wash just to stand up on a wet deck. The problem with even doubled joists is a build up of crud that is much harder to remove than over single 2x's. A flat board, or several, is a magnet for fuzzy green stuff.

Second, we can't butt deck boards here. They need to air and dry quickly, or they rot between the boards far faster. I even gap them wider than the normal 3/16th inch so our maple seeds will slip through. I will be covering all the joists with protective tape, mainly because there are so many nail holes. Wood over the joists is not a problem. That connection is pretty dry when we get up to 80 days and 80 nights of rain, and the rest of winter is foggy.

Finally, to spare the grief of seeing so many nails, there only needs to be one attachment point, and that at the main joists. Cedar doesn't warp and twist like pressure treated pine or fir. Just stick it down; it molds to shape and minds. I will also be using Camo connections which penetrate just shy of the top corner of the boards. I hope they work..... They could resolve a lot of problems.
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#26
  Re: New Decking, at Least by hbmcc (About three/four yea...)
There have been many improvements made in the science of building better and longer lasting decks. One of those is covering end cuts of posts with a waterproof membrane. Waterproof membranes have been widely used in construction everywhere and generally available at most lumberyards and home improvement centers. Bolting beams saddled to sides of posts is not a proper deck construction method and maybe against local building code.
Any free advice given is worth double price paid.
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#27
  Re: RE: New Decking, at Least by Woodenfish (There have been many...)
(07-26-2019, 01:56 PM)Woodenfish Wrote: There have been many improvements made in the science of building better and longer lasting decks. One of those is covering end cuts of posts with a waterproof membrane. Waterproof membranes have been widely used in construction everywhere and generally available at most lumberyards and home improvement centers. Bolting beams saddled to sides of posts is not a proper deck construction method and maybe against local building code.

The issue is not brackets at the top of posts supporting deck beams. The problems occur when the pressure treated post is cut up, destroying the protective layer it once had. Treatment rarely extends deeper than a half inch. I noticed the standards are cheaper now, with only 0.4-inches of treatment listed on the label. 

And, yes, any cross cut, or cut that removes the treated portion needs to be field treated (painted) and protected with a waterproof/pest proof seal.

Onward! Still alive!
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#28
  Re: New Decking, at Least by hbmcc (About three/four yea...)
I may as well add some journalistic chatter......

Today was hot! The AC wanted to kick on at 10 with the thermostat set at 76. Temperature at the deck, in shade, was 80. It eventually would reach 95 in our section of town, at 3p. A usual day is the AC sputtering to a start at about 3. We are the rare home with central AC; it is not common in Puget Sound due to predominantly cool temperatures. We put it in 10 years ago for my wife who has MS. The last two weeks of July are the hottest of the summer. The highest eTO weeks.

Have a two-foot cantilever where I experiment with protecting the house. Redoing base protection needs to be done before any decking is installed. I reached for the new metal flashing and burned my fingers. 

Took a break for lunch and promptly broke the old garbage disposal. Not my day. HD had four Badgers with stainless interiors which probably don't prevent the case from fracturing, which is now the normal death cry. 

But I was hot and irritated by the stupid collar that has one screw on the outlet in a blind position; and the crazy things must be perfectly aligned in order to thread. The visible screw was next to impossible to thread. Once it is done the second, blind one is easier. 

Gave up and painted some new siding with primer. It was 95 and my eyeballs were burning from sweat.

Finished fishing for screw threads after dinner. The new disposal worked and was dry as Death Valley. Amazing! That never happens.

No pictures of drudgery chores.

Next, some pictures of new crappy flashing that's 4-inches tall and covers the first course of siding.
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#29
  Re: New Decking, at Least by hbmcc (About three/four yea...)
A few images...
   
The first two courses of siding and decking are removed. That twisty metal is the original flashing. About an inch-and-half of loose metal is behind the bevel siding. Siding rotted only where in contact with deck boards. Flashing was attached to the ledger every 16, plus some more. What follows is the "fix" to this "problem".

   
Not new flashing. And, look Ma', no sheathing. Just building felt. I think '85 was near the cutoff for no solid sheathing on homes. My home only cracks drywall at seams during an earthquake. 

Opened the wall for waterproofing and some pest deterrent. What's not shown is wads of wet Borax rubbed into the cracks. More bug deterrent. The floor underlayment was shy of the plate line a few fractions. I don't know why but I had to buy some insulation foam to seal that area.

   
Insulation does not bead like caulk. I spent *more* time chasing strings of expanding foam....

   
Well over half of the stiff foam was cut away. I am happy now, and have four more cans of foam in the Lowes bag. It only took one can to do 18 feet plus a couple cavities. No coverage is listed on the cans.

Also, the first few feet of tar tape (Vycor) are patched onto the joists. The next two strips and most of the 75 feet of tape will protect the ledger and 4 vertical inches of plate and studs. What can I say.... I over design and over build.

   
Tar tape overlays the joist patches. 

   
Ready for metal flashing, twice the width of what was there originally. The bevel siding that is there will act as a backer to the metal flashing and disappear. 

A new deck board keeps four shuffling paws and the attached dog from falling through the 8-inch gaps between joists. Well, that's my explanation.....

I don't know what is next.... Watch paint dry?
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#30
  Re: New Decking, at Least by hbmcc (About three/four yea...)
Now for some very unexciting stuff.... Cut up and nail in 120 feet of treated wood, or 88 chunks for blocking to make those intermediate "joists" actually do what they are supposed to do. All this blocking is extra work; never in the project plans.

Along with these extras, I need to block in pieces near end of decking for "nailers". That's another 88 chunks of blocking.
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