While searching the web for truss related things, I found this article
(PDF). I was not aware of this problem, but it makes sense. These
trusses are used in most large barns these days. What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. This could
cause the building to collapse. I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf

wrote in news:b8fbe895bc7bb68d5b7bvgm2hkhpbltboq@
4ax.com:

While searching the web for truss related things, I found this article
(PDF). I was not aware of this problem, but it makes sense. These
trusses are used in most large barns these days. What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. This could
cause the building to collapse. I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf




Upon reading this article, it appears to me that the problem only becomes a
significant one if solar panels are to be mounted to the roof.


--
Tegger

On Jan 4, 2:21*am, Tegger wrote:
wrote in news:b8fbe895bc7bb68d5b7bvgm2hkhpbltboq@
4ax.com:

While searching the web for truss related things, I found this article
(PDF). *I was not aware of this problem, but it makes sense. *These
trusses are used in most large barns these days. *What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. *This could
cause the building to collapse. *I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf

Upon reading this article, it appears to me that the problem only becomes a
significant one if solar panels are to be mounted to the roof.

--
Tegger

Are you really that dopey?

On Fri, 4 Jan 2013 02:12:50 -0800 (PST), harry
wrote:

On Jan 4, 2:21*am, Tegger wrote:
wrote in news:b8fbe895bc7bb68d5b7bvgm2hkhpbltboq@
4ax.com:

While searching the web for truss related things, I found this article
(PDF). *I was not aware of this problem, but it makes sense. *These
trusses are used in most large barns these days. *What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. *This could
cause the building to collapse. *I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf

Upon reading this article, it appears to me that the problem only becomes a
significant one if solar panels are to be mounted to the roof.

--
Tegger

Are you really that dopey?
That IS where the problem came to light.

A lot of agricultural trusses around here have plywood gussets
fastened with hot dipped galvanized nails and glue in place of the
porcupine plates.

harry wrote in
:



Are you really that dopey?


Not Dopey, but according to my wife I'm usually Grumpy.


--
Tegger

On Jan 3, 5:21*pm, wrote:
While searching the web for truss related things, I found this article
(PDF). *I was not aware of this problem, but it makes sense. *These
trusses are used in most large barns these days. *What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. *This could
cause the building to collapse. *I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf

Well if you have a problem, get up there and give a dose of WD40 once
a year or so.

harry wrote in news:a249fcaf-601c-4a89-b41b-
:



Well if you have a problem, get up there and give a dose of WD40 once
a year or so.




WD-40 is neither a lubricant nor a protectant. And oil of any kind isn't a
great idea on structural wood. I wonder about something like POR-15? I'm
not going to re-read the article, but I think I remember that it hints at
such epoxy treatments.


--
Tegger

On Fri, 4 Jan 2013 23:53:47 +0000 (UTC), Tegger
wrote:

harry wrote in news:a249fcaf-601c-4a89-b41b-
:



Well if you have a problem, get up there and give a dose of WD40 once
a year or so.




WD-40 is neither a lubricant nor a protectant. And oil of any kind isn't a
great idea on structural wood.

Tung? Linseed? ;-)

I wonder about something like POR-15? I'm
not going to re-read the article, but I think I remember that it hints at
such epoxy treatments.

Rot Doctor sells epoxy treatments that work very well. I've used it on
some pretty punky wood with success. OTOH, once the structural
strength is gone, there's not much that bring it back other than
another structural piece. IMO, you can stop the damage but the clock
only goes one direction.

wrote in :

On Fri, 4 Jan 2013 23:53:47 +0000 (UTC), Tegger
wrote:

harry wrote in
news:a249fcaf-601c-4a89-b41b-
:



Well if you have a problem, get up there and give a dose of WD40
once a year or so.




WD-40 is neither a lubricant nor a protectant. And oil of any kind
isn't a great idea on structural wood.

Tung? Linseed? ;-)




Touche. I was thinking of hydrocarbon oils rather than those derived from
carbohydrates. Should have been more precise in my original comment. WD-40
contains hydrocarbons.




I wonder about something like POR-15? I'm
not going to re-read the article, but I think I remember that it hints
at such epoxy treatments.

Rot Doctor sells epoxy treatments that work very well. I've used it on
some pretty punky wood with success. OTOH, once the structural
strength is gone, there's not much that bring it back other than
another structural piece. IMO, you can stop the damage but the clock
only goes one direction.



Right. But an anti-corrosion (oxygen-excluding) epoxy would prevent the
steel from rotting, and steel-corrosion was the point of the article
referenced originally.



--
Tegger

On Fri, 4 Jan 2013 02:14:04 -0800 (PST), harry
wrote:

On Jan 3, 5:21*pm, wrote:
While searching the web for truss related things, I found this article
(PDF). *I was not aware of this problem, but it makes sense. *These
trusses are used in most large barns these days. *What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. *This could
cause the building to collapse. *I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf

Well if you have a problem, get up there and give a dose of WD40 once
a year or so.

WD40 only lasts a few days at most. If I was going to use anything, I'd
probably coat them with tar. Melted parafin wax would probably work
well too, and not be as ugly as tar. What also comes to mind would be a
spray paint that would protect the metal as well as the wood, but it
would have to be a paint that adheres to galvanized metal. Ideally, the
truss plates should be painted on *both* sides BEFORE they are
installed.

On Jan 5, 4:06*am, wrote:
On Fri, 4 Jan 2013 02:14:04 -0800 (PST), harry

wrote:
On Jan 3, 5:21*pm, wrote:
While searching the web for truss related things, I found this article
(PDF). *I was not aware of this problem, but it makes sense. *These
trusses are used in most large barns these days. *What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. *This could
cause the building to collapse. *I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf

Well if you have a problem, get up there and give a dose of WD40 once
a year or so.

WD40 only lasts a few days at most. *If I was going to use anything, I'd
probably coat them with tar. *Melted parafin wax would probably work
well too, and not be as ugly as tar. *What also comes to mind would be a
spray paint that would protect the metal as well as the wood, but it
would have to be a paint that adheres to galvanized metal. *Ideally, the
truss plates should be painted on *both* sides BEFORE they are
installed.

Well you must have different WD40 in the USA.
In the UK it leaves an oily film behind. Indoors it is virtually
permanent.
I spray the painted steel enclosures on my electrical switchgear in
outbuildings to stop it corroding, works fine.
Also garden tools after use to stop them rusting.

I have seen stainless steel truss plates over here. Sometimes called
gangnails.
Virtually all new domestic buildings here have trussed roofs here.
You can buy standard ones or have specials made up.

On Fri, 04 Jan 2013 22:06:13 -0600, wrote:

On Fri, 4 Jan 2013 02:14:04 -0800 (PST), harry
wrote:

On Jan 3, 5:21*pm, wrote:
While searching the web for truss related things, I found this article
(PDF). *I was not aware of this problem, but it makes sense. *These
trusses are used in most large barns these days. *What is happening is
the moisture from animals, and ammonia from the manure is building up on
the truss plate connectors and causing them to corrode. *This could
cause the building to collapse. *I thought I'd share the article.

http://www.omafra.gov.on.ca/english/...cts/10-071.pdf

Well if you have a problem, get up there and give a dose of WD40 once
a year or so.

WD40 only lasts a few days at most. If I was going to use anything, I'd
probably coat them with tar. Melted parafin wax would probably work
well too, and not be as ugly as tar. What also comes to mind would be a
spray paint that would protect the metal as well as the wood, but it
would have to be a paint that adheres to galvanized metal. Ideally, the
truss plates should be painted on *both* sides BEFORE they are
installed.

Ideally the truss plates would be hot dip galvanized, and the wood
treated with a non-metallic preservative - like blue-wood, or an oil
preservative, such as linseed.

On Sat, 05 Jan 2013 13:26:50 -0500, wrote:

Ideally the truss plates would be hot dip galvanized, and the wood
treated with a non-metallic preservative - like blue-wood, or an oil
preservative, such as linseed.

In the article they said that the metal is galvanized (which it is).
But when the pins are punched into it, all those edges are bare metal.
Those pins are not that thick, so rust could begin to eat away at them
and not take long to eat thru. They should be galvanized AFTER they are
made.

The trusses I've seen are just bare wood. I have not seen treated
lumber used, but I suppose it could be custom made. But standard
treated wood contains a lot of copper, and that would affect the steel
plates.

On Sat, 05 Jan 2013 13:31:36 -0600, wrote:

On Sat, 05 Jan 2013 13:26:50 -0500, wrote:

Ideally the truss plates would be hot dip galvanized, and the wood
treated with a non-metallic preservative - like blue-wood, or an oil
preservative, such as linseed.

In the article they said that the metal is galvanized (which it is).
But when the pins are punched into it, all those edges are bare metal.
Those pins are not that thick, so rust could begin to eat away at them
and not take long to eat thru. They should be galvanized AFTER they are
made.

That's why I said "hot dipped" All hot dipped parts are dipped after
fabrication.

The trusses I've seen are just bare wood. I have not seen treated
lumber used, but I suppose it could be custom made. But standard
treated wood contains a lot of copper, and that would affect the steel
plates.

wrote in message
news
On Sat, 05 Jan 2013 13:26:50 -0500, wrote:

Ideally the truss plates would be hot dip galvanized, and the wood
treated with a non-metallic preservative - like blue-wood, or an oil
preservative, such as linseed.

In the article they said that the metal is galvanized (which it is).
But when the pins are punched into it, all those edges are bare metal.
Those pins are not that thick, so rust could begin to eat away at them
and not take long to eat thru. They should be galvanized AFTER they are
made.

The trusses I've seen are just bare wood. I have not seen treated
lumber used, but I suppose it could be custom made. But standard
treated wood contains a lot of copper, and that would affect the steel
plates.

When I worked in a truss shop quite awhile ago an order came through for
large mono trusses that were to added to an existing shopping center to
create an exterior overhang\walkway. The village required the lumber used to
be "fire resistant" and it turned out that the chemicals in this treated
lumber would cause the galvanization to deteriorate. The only option at the
time was to use stainless steel plates which were very expensive. We never
built the trusses but the overhang did go up although I don't know how it
was constructed.