I notice the old fences around all have 2 horizontal rails for the
boards to attach to.  I've also noticed that new specs often show 3
rails, without comment.  I'm thinking that this might be due to the
fence boards being much thinner than they used to be.

I like to place my rails long side vertical, so I don't get excessive
sagging over time.  But I'm thinking that unless I expect the fence to
see hard wind loads or other severe attacks (kicks, etc.), 2 rails
might be enough.

Any thoughts?

On May 11, 5:18=A0pm, mike  wrote:
> I notice the old fences around all have 2 horizontal rails for the
> boards to attach to. =A0I've also noticed that new specs often show 3
> rails, without comment. =A0I'm thinking that this might be due to the
> fence boards being much thinner than they used to be.
>
> I like to place my rails long side vertical, so I don't get excessive
> sagging over time. =A0But I'm thinking that unless I expect the fence to
> see hard wind loads or other severe attacks (kicks, etc.), 2 rails
> might be enough.
>
> Any thoughts?

Depends on the size of the rails, the size and weight of the fence
boards/pickets, the distance between the posts, the material of the
rails (vinyl over steel or aluminum, wood species), the aesethetic
sense of the the owner/installer, etc.

R

"mike" <y...@hotmail.com> wrote in message 
news:0...@v23g2000pro.googlegroups.com...
>I notice the old fences around all have 2 horizontal rails for the
> boards to attach to.  I've also noticed that new specs often show 3
> rails, without comment.  I'm thinking that this might be due to the
> fence boards being much thinner than they used to be.
>
> I like to place my rails long side vertical, so I don't get excessive
> sagging over time.  But I'm thinking that unless I expect the fence to
> see hard wind loads or other severe attacks (kicks, etc.), 2 rails
> might be enough.
>
> Any thoughts?

I've seen fences installed after Huricane Ike hit down here in Houston and 
the ones with two rails have boards warping and bowing like crazy.  I mean 
every board is going a different direction.  This is in more than just one 
neighborhood so it looks like the quality of fence board in general has gone 
down.  3 rails (top middle and bottom) may help with this warping issue.

On May 11, 2:25=A0pm, RicodJour  wrote:
> On May 11, 5:18=A0pm, mike  wrote:
>
> > I notice the old fences around all have 2 horizontal rails for the
> > boards to attach to. =A0I've also noticed that new specs often show 3
> > rails, without comment. =A0I'm thinking that this might be due to the
> > fence boards being much thinner than they used to be.
>
> > I like to place my rails long side vertical, so I don't get excessive
> > sagging over time. =A0But I'm thinking that unless I expect the fence t=
o
> > see hard wind loads or other severe attacks (kicks, etc.), 2 rails
> > might be enough.
>
> > Any thoughts?
>
> Depends on the size of the rails, the size and weight of the fence
> boards/pickets, the distance between the posts, the material of the
> rails (vinyl over steel or aluminum, wood species), the aesethetic
> sense of the the owner/installer, etc.
>
> R

2x4's.  PT Wood.  8 ft post spacing.

On Mon, 11 May 2009 14:18:01 -0700 (PDT), mike
<y...@hotmail.com> wrote:

>I notice the old fences around all have 2 horizontal rails for the
>boards to attach to.  I've also noticed that new specs often show 3
>rails, without comment.  I'm thinking that this might be due to the
>fence boards being much thinner than they used to be.

Are they much thinner, or are you only thinking that?  Serious
quesiton.  I can read your sentence either way.
>
>I like to place my rails long side vertical, so I don't get excessive
>sagging over time.  But I'm thinking that unless I expect the fence to
>see hard wind loads or other severe attacks (kicks, etc.), 2 rails
>might be enough.
>
>Any thoughts?

What kind of fence?  Rail? Picket? etc.?	

You plan to use 2x4's for rails?   When were rails ever that thick?
Even if they once were, thinner rails are used all over the place and
they are fine.

With a rail fence, three rails will each bear as much load as the two
rails would, and the load on the posts will be 50% higher. 

Mook, you don't say what kind of fence you're talking about either,
but if two rails warp, so will three.  

I have a picket fence, and plenty of the rails are 30 years old.  They
look just like they did 26 year, but a bit greyer.  Most are 8 feet
long.  They are shaped like a parenthesis on one side and straight on
the other.  They sell new, treated ones at Home Depot that are close
enough that even I don't notice that they don't match.  The new ones
are treated. 

On May 11, 6:02=A0pm, mm  wrote:
>
> With a rail fence, three rails will each bear as much load as the two
> rails would,

Each?  Not quite - each rail in a three rail fence will only have to
take 2/3 of the load on a rail in a two rail fence.

> and the load on the posts will be 50% higher.

The only difference is the weight of the rail and the additional
fasteners.  Not sure where you get the load difference numbers.

R

RicodJour wrote:
> On May 11, 6:02 pm, mm  wrote:
>> With a rail fence, three rails will each bear as much load as the two
>> rails would,
> 
> Each?  Not quite - each rail in a three rail fence will only have to
> take 2/3 of the load on a rail in a two rail fence.
> 
>> and the load on the posts will be 50% higher.
> 
> The only difference is the weight of the rail and the additional
> fasteners.  Not sure where you get the load difference numbers.
> 
> R
> 

Nobody else said it, so I will- how tall is the damn fence? For a short 
fence, 2 rails may be fine, but for a traditional 6-foot privacy fence, 
we always used 3. We also usually used alternating-side pickets with an 
overlap, so some wind could still blow through. Plus, that way, no 
arguments about who gets the pretty side.

--
aem sends...

mook johnson wrote:
> "mike" <y...@hotmail.com> wrote in message
> news:0...@v23g2000pro.googlegroups.com...
>> I notice the old fences around all have 2 horizontal rails for the
>> boards to attach to.  I've also noticed that new specs often show 3
>> rails, without comment.  I'm thinking that this might be due to the
>> fence boards being much thinner than they used to be.
>>
>> I like to place my rails long side vertical, so I don't get excessive
>> sagging over time.  But I'm thinking that unless I expect the fence
>> to see hard wind loads or other severe attacks (kicks, etc.), 2 rails
>> might be enough.
>>
>> Any thoughts?
>
> I've seen fences installed after Huricane Ike hit down here in
> Houston and the ones with two rails have boards warping and bowing
> like crazy.  I mean every board is going a different direction.  This
> is in more than just one neighborhood so it looks like the quality of
> fence board in general has gone down.  3 rails (top middle and
> bottom) may help with this warping issue.

My house backs up to a 200' wide power-line easement. The houses on my side 
of the easement all had their fences installed with metal posts. No a single 
fence came down during hurricane Yikes! The houses on the other side of the 
easement all had wooden posts. Almost all of them were flattened. 

On Mon 11 May 2009 06:41:56p, HeyBub told us...

> mook johnson wrote:
>> "mike" <y...@hotmail.com> wrote in message
>> news:0...@v23g2000pro.googlegroups.com.
>> .. 
>>> I notice the old fences around all have 2 horizontal rails for the
>>> boards to attach to.  I've also noticed that new specs often show 3
>>> rails, without comment.  I'm thinking that this might be due to the
>>> fence boards being much thinner than they used to be.
>>>
>>> I like to place my rails long side vertical, so I don't get excessive
>>> sagging over time.  But I'm thinking that unless I expect the fence
>>> to see hard wind loads or other severe attacks (kicks, etc.), 2 rails
>>> might be enough.
>>>
>>> Any thoughts?
>>
>> I've seen fences installed after Huricane Ike hit down here in
>> Houston and the ones with two rails have boards warping and bowing
>> like crazy.  I mean every board is going a different direction.  This
>> is in more than just one neighborhood so it looks like the quality of
>> fence board in general has gone down.  3 rails (top middle and bottom)
>> may help with this warping issue. 
> 
> My house backs up to a 200' wide power-line easement. The houses on my
> side of the easement all had their fences installed with metal posts. No
> a single fence came down during hurricane Yikes! The houses on the other
> side of the easement all had wooden posts. Almost all of them were
> flattened. 

Are you referring to the vertical posts in the ground?  What size were the 
wooden posts?  In our area they usually use pressure-treated 4x4's.  In 
almost all cases, whether pre-bilt panels or built in place, there are 
three rails supporting the vertical pickets.

-- 
                            Wayne Boatwright                            
------------------------------------------------------------------------
   Never work before breakfast; if you have to work before breakfast,   
               eat your breakfast first.  ~Josh Billings               

Wayne Boatwright wrote:
>>
>> My house backs up to a 200' wide power-line easement. The houses on
>> my side of the easement all had their fences installed with metal
>> posts. No a single fence came down during hurricane Yikes! The
>> houses on the other side of the easement all had wooden posts.
>> Almost all of them were flattened.
>
> Are you referring to the vertical posts in the ground?  What size
> were the wooden posts?  In our area they usually use pressure-treated
> 4x4's.  In almost all cases, whether pre-bilt panels or built in
> place, there are three rails supporting the vertical pickets.

Yeah, the vertical posts. Best I could tell (from 200' away) they were the 
standard 4x4s. The laterals were 2x4s, but it didn't make any difference. 
The wind snapped the vertical posts at ground level.

Truth be told, I suspect the posts were more than fifteen years old, mostly 
rotted, and required only a puff to tumble them over. Of course galvanized 
metal posts set in concrete don't rot, so...