Building and Construction - Concealed Joist Ties

Author

Concealed Joist Ties

hammer

2005-10-13, 3:21 pm

I have been designing a patio cover and would like to do some beam
(4x10") connections with Simson Strong Tie Concealed Joist Ties (CJTs)
for a clean look. Has anyone had any experience to use this product?

RicodJour

2005-10-13, 5:21 pm

hammer wrote:
> I have been designing a patio cover and would like to do some beam
> (4x10") connections with Simson Strong Tie Concealed Joist Ties (CJTs)
> for a clean look. Has anyone had any experience to use this product?

I've had experience, but never used the product. ;)

A couple or three caveats with that connection:
- It's only supposed to be used with glulams, LVLs, or well dried
lumber. If your patio cover is going to get wet it's probably better
to do it another way. The wood you'll most likely be using won't be
well-dried and/or pressure treated. Once it's outside and subject to
big swings in humidity, it might not behave so well.
- The connector will eventually rust though even though the connector
is galvanized. The galvanizing is a sacrificial coating and is not
"rust-proofing".
- You won't be able to visually examine the connection as it is totally
hidden. You won't know there is a problem until something unfortunate
happens.

I'd go with another way of making that connection or have stainless
steel connectors made up in a local shop.

R

Inexperienced Laborer

2005-10-15, 7:21 pm

How long would those sacrificial galvanized connectors take to fail?

How much do you estimate a local sheet metal shop would charge to make
some similar connectors from stainless steel?

"RicodJour" <ricodjour@worldemail.com> wrote in message
news:1129233352.344048.89310@g14g2000cwa.googlegroups.com...
> hammer wrote:
(CJTs)[color=darkred]
>
> I've had experience, but never used the product. ;)
>
> A couple or three caveats with that connection:
> - It's only supposed to be used with glulams, LVLs, or well dried
> lumber. If your patio cover is going to get wet it's probably better
> to do it another way. The wood you'll most likely be using won't be
> well-dried and/or pressure treated. Once it's outside and subject to
> big swings in humidity, it might not behave so well.
> - The connector will eventually rust though even though the connector
> is galvanized. The galvanizing is a sacrificial coating and is not
> "rust-proofing".
> - You won't be able to visually examine the connection as it is
totally
> hidden. You won't know there is a problem until something unfortunate
> happens.
>
> I'd go with another way of making that connection or have stainless
> steel connectors made up in a local shop.
>
> R
>

RicodJour

2005-10-15, 10:21 pm

Inexperienced Laborer wrote:[color=darkred]
> How long would those sacrificial galvanized connectors take to fail?
>
> How much do you estimate a local sheet metal shop would charge to make
> some similar connectors from stainless steel?
>
>
> "RicodJour" <ricodjour@worldemail.com> wrote in message
> (CJTs)
> totally

When people don't post in order it makes it harder to follow.

The life for exposed metal connectors is on the order of 15-20 years,
but can be substantially more or less depending on exposure. A
stainless connector would probably run me around $50 each. Maybe less
depending on how many I was getting. My first choice would be to
design a different connector. Multi-pin/bolt connectors lead to
splitting in anything but the driest lumber. That's why Simpson
indicates that the CJTs should only be used with LVLs, glulams or
well-dried lumber. Simpson also states, "If you choose to use ZMAX or
HDG on an outdoor project (i.e. deck, patio cover), you should
periodically inspect your connectors and fasteners or have a
professional inspection performed." A professional inspection of a
hidden connector is a guess. This is probably not the situation to be
guessing.

For those and other reasons, it's probably better to utilize a
different connector or method of connection.

R

hammer

2005-10-17, 6:21 pm

Thanks fellas,
I thought there might be some sort of problems because of the exterior
app factor.Besides all the large members that are rough sawn out here
are green and I don`t think the conection would remain 100% after a few
years.
h...

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