pergola support
#21
(09-05-2017, 10:26 PM)MstrCarpenter Wrote: The "big orange store" has 9' long 4x4 post sleeves for about $23. They have a little play to help plumb your posts, and you could still provide necessary drainage. I would still make sure the posts are rated for structural ground contact. (it used to be that common P.T. was .40 and structural ground contact was .60. In my opinion, the older treatment was a lot better.)
I think with a little research and a few calls, you might find that steel tube with leveling plates welded on the bottom and connection plates welded on top would yield superior results for the same or less $ as the Simpson hdwr. and they would last forever if protected from water. Your 10"-12" dia, footing could stop at the bottom of your pavers with 4 anchor bolts sticking up. The posts would be leveled and plumbed with nuts on top and bottom of the leveling plate, then the remaining space filled with structural flow-able grout. I've only brought this up because, even with a "lifetime warrantee" against rot or decay, I would not want to replace the posts in ten or fifteen years when the grape vines or roses have evolved into a permanent (prominent) part of your landscape.

Are talking about the PVC post sleeves? Aren't they purely decorative?
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#22
(09-05-2017, 12:29 PM)Bope Wrote: These look interesting. I originally was thinking of the post connectors that bolt to the top of the concrete footer with a J bolt. Where would I purchase these? My google search sis not turn up a place to buy them. Any tips on setting these? It looks like they want 4" of concrete around the MPB44Z post base, that means a 12" sonotube. Witht he posts covered with the stone pillars that should be easily hidden. The posts by the house I was hoping to only use a 6" tube therefore being able to hide the top of the the concrete with trim.

Check your local lumber yard or masonry supply yard. My local lumber yard has them. HD can probably order them if they don't have them in stock. 

Here is how I would install the post bases. Set the top of the 12" sonotube at the finish grade of the pavers. Using a form stake on each side, span the sonotube with a piece of 6x6. Attach the post base to the 6x6, making sure it's properly located and plumb. The bases apparently have holes for this purpose. Pour the concrete. I'm not a contractor so your guy may have a better way to do it. Also, Jason said he has used these bases before, so he may have some suggestions.

Regarding the rear posts, 6" diameter footings are too small for this type of post base. You're going to have to rethink the rear posts.
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#23
(09-06-2017, 10:53 AM)Bope Wrote: Are talking about the PVC post sleeves? Aren't they purely decorative?

Yes they are; but in this case they could be used as a stay in place concrete form. They would be easy to cut flush with the concrete after its set, and would provide for drainage and post replacement. Personally I would go for the structural steel. About $85 would cover 3" x 3" x 24' with 1/8" walls. That's 6 posts for around $200. I don't know much 6, 12' ground contact SYP. P.T. 4x4's and their bases would cost, but I do know the steel posts will stay straight.
Sign at N.E. Vocational School Cabinetmaking Shop 1976, "Free knowledge given daily... Bring your own container"
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#24
I thought about this over the weekend as I was thinking about how I would build the pergola. The back posts are under the eave so having to slide the post down a tube would be difficult. I think for those I am going to pour an 8" sonotube to the bottom of the paver base and extend that up with a 6" tube with a J bolt post base on the top. The ones away form the house I will either use a MPB in an 8" sonotube or just use a PVC sleeve to the bottom of the concrete.
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#25
(09-11-2017, 02:02 PM)Bope Wrote: The ones away form the house I will either use a MPB in an 8" sonotube or just use a PVC sleeve to the bottom of the concrete.

The MPB44Z base requires a minimum of 4 inches of sidecover on all four sides, so the foundation needs to be a minimum of 12 inches in diameter.
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#26
Here's a way to use MPB44Z bases for all four posts. Install four 12-inch diameter sonotubes so the tops are 1 inch below the bottom of the pavers. Support the MPB bases over the sonotubes. If the roof overhang interferes with the rear post placement, put the base on the post, hold it in place with a couple of screws and tip the post into the sonotube. Pour the foundations and let them cure. 

What you should have now are all four MPB bases extending 8-1/4 inches (7-1/4" + 1") above the foundations. Install the posts in the bases. Place the leveling sand and the pavers, including up to and around the bases. Leave a 1/2-inch gap all around between the bases and the pavers for air circulation. Any water that flows in around the bases will drain away in the sand. The cedar wrap on the posts will cover the 1/2-inch gaps around the bases.

http://www.icc-es.org/Reports/pdf_files/ESR-3050.pdf -- See Table 8 and Figure 8 for MPB dimensions
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#27
If anyone is interested these moment post bases from Simpson are $99 each. I think I am just going to go with these from Lowes. Simpson makes a similar post base for $85. I think I will use the $20 version from USP. I just wish they were 3 or 4 sided instead of just 2 sided. The guy at the Tool Barn helping me with the Simpson products suggested using these post stakes. They are just powder coated steel and I wonder how they would hold up to being cast in concrete.
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#28
(10-03-2017, 06:40 AM)Bope Wrote: If anyone is interested these moment post bases from Simpson are $99 each. I think I am just going to go with these from Lowes. Simpson makes a similar post base for $85. I think I will use the $20 version from USP. I just wish they were 3 or 4 sided instead of just 2 sided. 

If you've decided to use bolt-down bases instead of moment bases, I would use this base. They're three sided, made for 4x4 PT posts and the instructions show how to position the four bases to provide rigidity to the structure.

http://www.homedepot.com/p/New-England-A...ZAodEEcNbQ

https://newenglandarbors.com/products/bo...et-system/

http://newenglandarbors.com/wp-content/u...ctions.pdf

Three 1/4-inch concrete screws are used to attach each base to its concrete foundation. I would probably drill a 1/2-inch hole in the bottom of each base and replace one of the concrete screws with a 1/2-inch wedge anchor. Drill a recess in the bottom of each post for the nut on the wedge anchor. The bases are plumbed, if necessary, with washers per the instructions. Some of the reviewers recommended replacing the concrete screws that come with the bases with better quality screws (Tapcon?).
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#29
(10-04-2017, 02:06 AM)Lynden Wrote: If you've decided to use bolt-down bases instead of moment bases, I would use this base. They're three sided, made for 4x4 PT posts and the instructions show how to position the four bases to provide rigidity to the structure.

http://www.homedepot.com/p/New-England-A...ZAodEEcNbQ

https://newenglandarbors.com/products/bo...et-system/

http://newenglandarbors.com/wp-content/u...ctions.pdf

Three 1/4-inch concrete screws are used to attach each base to its concrete foundation. I would probably drill a 1/2-inch hole in the bottom of each base and replace one of the concrete screws with a 1/2-inch wedge anchor. Drill a recess in the bottom of each post for the nut on the wedge anchor. The bases are plumbed, if necessary, with washers per the instructions. Some of the reviewers recommended replacing the concrete screws that come with the bases with better quality screws (Tapcon?).

I like these. Three sided sounds much more secure since the pergola is going to be free standing. The question I have is these look like they have a nice about 1" deep cup to hold water on the bottom of the 4x4. I wonder about making a stand off with some galvanized sheet. The stand off would allow the water to run off and it could cover the nut end of a J bolt to hold it down. I am pouring new footers so I can use J bolts. Probably wouldn't hurt to drill a couple holes on the sides near the bottom to allow that water to run out.
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#30
(10-04-2017, 07:10 AM)Bope Wrote: The question I have is these look like they have a nice about 1" deep cup to hold water on the bottom of the 4x4. I wonder about making a stand off with some galvanized sheet. The stand off would allow the water to run off and it could cover the nut end of a J bolt to hold it down. I am pouring new footers so I can use J bolts. Probably wouldn't hurt to drill a couple holes on the side near the bottom to allow that water to run out.

I wouldn't use a standoff in the bottom of the base. The 1" pocket is there for a purpose, to lock the bottom of the post into the base. If you want to put something under the post, use 2 or 3 thicknesses of hardware cloth. Drilling a couple of holes on one side of the base near the bottom is OK. As an added protection against rot, pour some copper-green preservative into a tin can and let the bottom of each post soak for a few hours.

http://www.homedepot.com/p/1-qt-Copper-G...Green+1+qt.

http://www.homedepot.com/p/Everbilt-1-2-.../205960835
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