Use of GRK structural screws

[theoldwizard1]

GRKs are certainly convenient when attaching a ledger board to a post (as opposed to notching the post and "letting in" the board). RSS come in 3 sizes, 1/4", 5/16", and 3/8". For a 12" ledger board going into 6x6 laminated post being used as a truss carrier, what size and how many screws per post (8' spacing).

 

[tarmy]

I am rebuilding my deck and am using those a lot. Friggin‘ great for attaching ledger and various things. Expensive and worth every penny…

 

[dscheidt]

GRKs are certainly convenient when attaching a ledger board to a post (as opposed to notching the post and "letting in" the board). RSS come in 3 sizes, 1/4", 5/16", and 3/8". For a 12" ledger board going into 6x6 laminated post being used as a truss carrier, what size and how many screws per post (8' spacing).

If I understand your description, prescriptive code essentially everywhere requires a hanger for that. (A simpson DJTZ or similar.) You'd use whatever is required by the hanger. If you have an engineered deck, you do what the drawing says. There are very good reasons prescriptive code requires steel there, this is one of the joints that fails and kills people.

 

[jack stand]

5-6, and if you feel uncomfortable still, adding another support to the face of the post gives you more opportunity (space) for additional screws. I'm sure you know what you're fighting is shearing of the fasteners and these "new" structural screws put common grade 2 lags and carriage screws to shame (size x size).

 

[theoldwizard1]

5-6, and if you feel uncomfortable still, adding another support to the face of the post gives you more opportunity (space) for additional screws.

3/8" ?

Because 2 truss carriers meet at the face of a 6x6 laminated post, you real can only get 4 screws in each board. I have thought about adding a 2' or 3' 2x6 to face of the post just under there truss carrier. This gives a "ledge" for the carrier to rest on. You could easily use 8 or 10 more GRKs on this support.

 

[WisJim]

When I built my garage last summer, we were required to either use joist hangers or notch the post for the ledger to sit. The screws don't actually support any vertical load.

 

[MoonRise]

If you were building a deck, all beam-to-post connections MUST be either let-in (notch the top of the post so that the beam is resting ON the notch ledge) OR you can use a post-to-beam metal connector with the beam resting on top of the post and the metal connector connecting the beam to the post.

The beam MUST rest on top of the post somehow. Either on top of the post (using a beam-to-post metal connector) or resting on a notch (ledge) cut into the post. You can NOT rely on the fasteners to hold a beam to the post, you have to have the beam resting on the post.

If you are working or dealing with a pole barn or post-and-beam structure, you will have to follow both the 'engineered' plans for the structure (the ones submitted and approved for the building permit) and the applicable local building Codes (which should have been used to approved the submitted plans for the permit ).

The plans and the Code both will specify the (minimum) acceptable 'correct' attachment method(s) and the fastener method(s) or options.

Deck building Codes and requirements have changed over the last (20?) years because of multiple deck structural failures, with damage and injury and fatalities.

Remember that Code just specifies the MINIMUM requirements. For example, Code may say the minimum required size is a 2x6. That means you can't use a 2x4 there, but can use a 2x8. Code may say you have to use a minimum of 6 16D nails for a connection, that means you can't use 10D nails or only use 4 16D nails. Code may say you have to use minimum 1/2" (nominal) thick sheathing, that means you can't use 3/8" (nominal) but could use 5/8" (nominal) sheathing there. Etc.

Although I like GRK (or similar) structural screws, they may or may not be rated/allowed for the connection you are considering. Check the Code and permit and plans for what to use on the specific connection.

(based on what the Code requirements are for decks and a similar beam/ledger to post connection, I'd really lean towards doing your pole building or post-and-beam structure using similar construction guidelines. Notch the post and rest the ledger/beam on the notch or use rest the beam/ledger on top of the post connected with a beam-to-post metal connector. With the appropriate specified fasteners.)

example: https://sutherlands.com/article/post-frame-building-basics/59

 

[Wrench97]

Not being sure what a GRK is I googled an image............................


I don't think that will do a very good job holding a deck up.....................................

 

[jack stand]

5-6, and if you feel uncomfortable still, adding another support to the face of the post gives you more opportunity (space) for additional screws. I'm sure you know what you're fighting is shearing of the fasteners and these "new" structural screws put common grade 2 lags and carriage screws to shame (size x size).

GRKs are certainly convenient when attaching a ledger board to a post (as opposed to notching the post and "letting in" the board). RSS come in 3 sizes, 1/4", 5/16", and 3/8". For a 12" ledger board going into 6x6 laminated post being used as a truss carrier, what size and how many screws per post (8' spacing).

I should have asked what your building, but I assumed that your "laminated posts" were "engineered" lvl posts. If you mean 3 - 2x6's assembled on site, I'd suggest screwing on another ply for support even if it's on the side face of the 3 2x6's.
Check your fasteners load rating but in many situations the grk RSS series and some by Simpson will do the job perfectly.

 

[theoldwizard1]

5-6, and if you feel uncomfortable still, adding another support to the face of the post gives you more opportunity (space) for additional screws. I'm sure you know what you're fighting is shearing of the fasteners and these "new" structural screws put common grade 2 lags and carriage screws to shame (size x size).

Yes, GRKs are much better than lags or carriage (?) screws but how about compared to a 20d or 30d common nail ?

 

[jack stand]

Right now I'm doing a job and blending in "Maize" pole barn nails that I believe are hardened, they are screw shank and you can watch them actually screw in their 5 and 6" and more economical than all .80 cent structural screws (even by the 400 pc. Box)
Common nails- I'm not sure that their not just pressed out of wire and to get the proper shear strength, they just make it very thick. This leads to damaging (splitting) lumber making the connection poor and sometimes the damage is hidden from plain sight.
I'm not a metallurgist, scientist or engineer, just an observant "nail bender" with a lot of years of splinters and bandaids.

 

[MoonRise]

Although nails and screws are both fasteners and both can be used to build things,

They
are
NOT
the
same thing!

Sometimes you can use a nail, sometimes you can use a screw/bolt, sometimes you can use either.

But not always.

Beam-to-post connection (at least with decks) HAS to be a through bolted connection (no screws or nails) and the beam has to be resting on the post (on top of the post and use a metal Simpson-type beam-to-post connector OR notch the post to make a ledge and the beam sits on the ledge). The fasteners hold the beam in place but do NOT (directly) carry the load. The load is from the beam 'resting' physically ON the post somehow (on top or on the notch ledge).

NO having the beam being supported only by the fastener(s) (in shear loading).

Nails can work loose over time (vibration, wood shrinkage, load direction, etc). So where it is 'critical' that the fastener never-ever loosen, screws or a through bolt are often specified.

 

[240sxguy]

Although nails and screws are both fasteners and both can be used to build things,

They
are
NOT
the
same thing!

Sometimes you can use a nail, sometimes you can use a screw/bolt, sometimes you can use either.

But not always.

Beam-to-post connection (at least with decks) HAS to be a through bolted connection (no screws or nails) and the beam has to be resting on the post (on top of the post and use a metal Simpson-type beam-to-post connector OR notch the post to make a ledge and the beam sits on the ledge). The fasteners hold the beam in place but do NOT (directly) carry the load. The load is from the beam 'resting' physically ON the post somehow (on top or on the notch ledge).

NO having the beam being supported only by the fastener(s) (in shear loading).

Nails can work loose over time (vibration, wood shrinkage, load direction, etc). So where it is 'critical' that the fastener never-ever loosen, screws or a through bolt are often specified.

This is interesting, I have a deck on my house that was converted to a three seasons room and some of the "legs" are bolted, but they basically sandwiched the post between two 2x10s or 2x12s (I don't remember which) so the bolts are in shear. I am actually revitalizing that part of the house so it sounds like it may be wise to do a little re-engineering to make it safer long term.

EDIT- It's also possible those posts continue up the wall into the room above. I won't know until it's opened up.

 

[MoonRise]

This is interesting, I have a deck on my house that was converted to a three seasons room and some of the "legs" are bolted, but they basically sandwiched the post between two 2x10s or 2x12s (I don't remember which) so the bolts are in shear. I am actually revitalizing that part of the house so it sounds like it may be wise to do a little re-engineering to make it safer long term.

EDIT- It's also possible those posts continue up the wall into the room above. I won't know until it's opened up.

If the 'beams' (whether two 2x10 or 2x12 or whatever) are 'sandwiching' the post and through bolted to connect them, that does NOT meet Deck Code (and has not for several years, like 20+ years).

The 'beam' MUST be either on top of the post (and connected with a metal Simpson-type beam-to-post connector) OR let-into a notch (or notches) in the post and then sitting on the 'ledge' made by the notch(es) (and connected with the specified size and type of through-bolted fasteners).

If your 'posts' are not the actual deck posts that go down to the footings in the ground but are the old hand rail or support rail posts but are now somehow being used as some structural element in the walls or whatnot, then they still probably don't meet the required structural requirements.

And also for a deck, since that typically uses PT lumber (at least for the structural part of it, the deck boards and trim might be something else) and the 'new' (again, like 20+ years now) AZQ PT is EXTREMELY corrosive to fasteners and hardware, you MUST use the appropriately PT rated fasteners and hardware. If the fastener/hardware does not explicitly state that it is rated for use with AZQ, then it is considered NOT rated to use with AZQ PT lumber.

And no, a 'builder' saying 'but I always build it like this and it's fine, trust me' is WRONG and is not meeting the minimum REQUIRED building Codes. (which is some of what led to the structural failures of decks and the fatalities and thus the updated and more stringent deck building Codes).

 

[240sxguy]

If the 'beams' (whether two 2x10 or 2x12 or whatever) are 'sandwiching' the post and through bolted to connect them, that does NOT meet Deck Code (and has not for several years, like 20+ years).

The 'beam' MUST be either on top of the post (and connected with a metal Simpson-type beam-to-post connector) OR let-into a notch (or notches) in the post and then sitting on the 'ledge' made by the notch(es) (and connected with the specified size and type of through-bolted fasteners).

If your 'posts' are not the actual deck posts that go down to the footings in the ground but are the old hand rail or support rail posts but are now somehow being used as some structural element in the walls or whatnot, then they still probably don't meet the required structural requirements.

And also for a deck, since that typically uses PT lumber (at least for the structural part of it, the deck boards and trim might be something else) and the 'new' (again, like 20+ years now) AZQ PT is EXTREMELY corrosive to fasteners and hardware, you MUST use the appropriately PT rated fasteners and hardware. If the fastener/hardware does not explicitly state that it is rated for use with AZQ, then it is considered NOT rated to use with AZQ PT lumber.

And no, a 'builder' saying 'but I always build it like this and it's fine, trust me' is WRONG and is not meeting the minimum REQUIRED building Codes. (which is some of what led to the structural failures of decks and the fatalities and thus the updated and more stringent deck building Code

This was done a LONG time ago, I am sure it was 20+ years ago.

I am going to do a bit more homework, but since I have it all opened up to clean out old insulation and 60 pounds of mouse **** I may go ahead and "update" the structure to make it safer, which is why I asked.

First thing I am going to do is call the township Monday and see if there was any record of this "structure" being built with a permit. If there isn't, I will have the inspector come out and look at it. It's a bit of a can of worms but I think it's "upgradable" with some cash and a couple weekends of labor to make sure it's it safe.

 

[Ton ton]

Right now I'm doing a job and blending in "Maize" pole barn nails that I believe are hardened, they are screw shank and you can watch them actually screw in their 5 and 6" and more economical than all .80 cent structural screws (even by the 400 pc. Box)
Common nails- I'm not sure that their not just pressed out of wire and to get the proper shear strength, they just make it very thick. This leads to damaging (splitting) lumber making the connection poor and sometimes the damage is hidden from plain sight.
I'm not a metallurgist, scientist or engineer, just an observant "nail bender" with a lot of years of splinters and bandaids.

I like Maze nails too. They sell quite a variety of nails. I'm not a metallurgist either.

 

[mike93lx]

Yes, GRKs are much better than lags or carriage (?) screws but how about compared to a 20d or 30d common nail ?

GRK is a brand, not a type or size of screw. They are not the only game in structural screws, either