[TowerTalk] Subject: How do bldg inspectors handle screw in earth anchors?
Earl Morse
kz8e at wt.net
Sat Jul 12 09:13:20 EDT 2014
It sure does depend on the building inspector. I have had inpectors that crawled all over the place, wanting the drawings, prints, engineer approvals and asking for information that they really didn't need but you provide just to get them to approve your installation.
I have had others that stamped a rough sketch on a fast food napkin and didn't even come out to the site.
Figure out what the guy wants and get it to him and get the ordeal over with before he can think of something else to ask you to provide.
In the QTHs I have lived I couldn't imagine using a screw-in anchor though. The soils guys can confirm this but the pull out force is essentially based on a cone of soil with the point at the anchor screw. The soil composition determines the slope of the cone. For some soil that slope changes with factors like how saturated with water the soil is. In Houston, you could have a nice big cone of soil holding that anchor in on a dry day and after a weeks worth of saturating rain you could pull a screw-in anchor out by hand with a large sucking sound.
Earl
N8SS
----------------------------------------------------------------------
Message: 1
Date: Thu, 10 Jul 2014 10:29:40 -0700
From: "Richard (Rick) Karlquist" <richard at karlquist.com>
To: towertalk at contesting.com
Subject: [TowerTalk] How do bldg inspectors handle screw in earth
anchors?
Message-ID: <53BECD84.7040802 at karlquist.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Has anyone had experience getting a building permit
for a tower with screw in earth anchors? How does
it get "inspected". There is no empty hole for
the inspector to look at. Do you show him the anchor
before insertion? If you have an authorized AB
Chance installing contractor put in the anchor,
do they issue a certificate that you can show the
inspector? In a sense, this contractor is also
the engineer and building inspector all in one.
Rick N6RK
------------------------------
Message: 2
Date: Thu, 10 Jul 2014 13:21:50 -0700
From: Jim Lux <jimlux at earthlink.net>
To: towertalk at contesting.com
Subject: Re: [TowerTalk] How do bldg inspectors handle screw in earth
anchors?
Message-ID: <53BEF5DE.8020406 at earthlink.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
On 7/10/14, 10:29 AM, Richard (Rick) Karlquist wrote:
> Has anyone had experience getting a building permit
> for a tower with screw in earth anchors? How does
> it get "inspected". There is no empty hole for
> the inspector to look at. Do you show him the anchor
> before insertion? If you have an authorized AB
> Chance installing contractor put in the anchor,
> do they issue a certificate that you can show the
> inspector? In a sense, this contractor is also
> the engineer and building inspector all in one.
>
could it be more like a material and process inspection?
You have the paperwork showing you have the anchor and the mfr's
paperwork showing what its properties are.
Then you have paperwork showing you did the installation appropriately
(e.g. if you used a truck mounted drive, it gives a reading of the
torque as it drove it)
The only time I've had an "official" inspection of a structure using
screw in anchors it was for a temporary installation, and the guy came
out, looked at the plans, looked at the erected contraption, verified
that what we had built matched the plans, and said "go for it".
Granted it was in an area and application where failure would hurt
nobody but ourselves.
What do utilities do when installing poles with these anchors? I find
it hard to believe that the city sends out an inspector to watch them
plant every pole and its guys.
------------------------------
Message: 3
Date: Thu, 10 Jul 2014 16:24:39 -0600
From: Brian Amos <bamos1 at gmail.com>
To: "towertalk at contesting.com" <towertalk at contesting.com>
Subject: Re: [TowerTalk] How do bldg inspectors handle screw in earth
anchors?
Message-ID:
<CAO2gF474ZEZd1saK8KY35TyC0PAtDYMyjRmcjf5ziaNBNhu7yw at mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
As for the utilities usually the municipality doesn't inspect their
installations as they are self regulating. The "screw anchors" ie
"helical piers" are installed to a certain torque which the software
tells the installation contractor he must meet. As a soil engineer I
have many times had to "inspect" the installation where I watch the
pressure gauge and make sure they make it to the required pressure
(which they tell me) for each pier and then I have to send a document
to the owner stating that it complies with the design and put my stamp
on it. I'm not a big fan of that setup as I don't do the engineering
but I have to certify that it will hold up. It drives me nuts
actually. For a residential purpose I would guess that you just tell
the building official when you will be installing it and they can come
and watch. That is the only way to really inspect them.
BTW: Is this for supporting the tower? Or is it for the guys? If it's
for the tower I suspect you will need at least one per leg and it must
be a large tower to keep them at least 3 screw diameters apart to
prevent interaction. This type of support provides virtually no
lateral resistance (especially the square chance bars that have no
soil contact anywhere but the helix, they are all tension and
compression, so for guy supports they work great, but not so well for
a foundation. I suspect that the building official won't care about
inspecting screws for a guying system. They usually only care about
the foundation itself.
Brian
KF7OVD
On Thu, Jul 10, 2014 at 2:21 PM, Jim Lux <jimlux at earthlink.net> wrote:
> On 7/10/14, 10:29 AM, Richard (Rick) Karlquist wrote:
>>
>> Has anyone had experience getting a building permit
>> for a tower with screw in earth anchors? How does
>> it get "inspected". There is no empty hole for
>> the inspector to look at. Do you show him the anchor
>> before insertion? If you have an authorized AB
>> Chance installing contractor put in the anchor,
>> do they issue a certificate that you can show the
>> inspector? In a sense, this contractor is also
>> the engineer and building inspector all in one.
>>
>
> could it be more like a material and process inspection?
> You have the paperwork showing you have the anchor and the mfr's paperwork
> showing what its properties are.
> Then you have paperwork showing you did the installation appropriately (e.g.
> if you used a truck mounted drive, it gives a reading of the torque as it
> drove it)
>
>
> The only time I've had an "official" inspection of a structure using screw
> in anchors it was for a temporary installation, and the guy came out, looked
> at the plans, looked at the erected contraption, verified that what we had
> built matched the plans, and said "go for it".
>
> Granted it was in an area and application where failure would hurt nobody
> but ourselves.
>
> What do utilities do when installing poles with these anchors? I find it
> hard to believe that the city sends out an inspector to watch them plant
> every pole and its guys.
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
------------------------------
Message: 5
Date: Thu, 10 Jul 2014 17:37:55 -0700
From: "Richard (Rick) Karlquist" <richard at karlquist.com>
To: Brian Amos <bamos1 at gmail.com>, "towertalk at contesting.com"
<towertalk at contesting.com>
Subject: Re: [TowerTalk] How do bldg inspectors handle screw in earth
anchors?
Message-ID: <53BF31E3.2010905 at karlquist.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
The screw in anchors, if used, would be for guying.
I guess you are saying that I must make the base big
enough to handle lateral force and I can't use the
guy anchors to hold the base in place. Got that.
So I have a choice of having my engineer watch
and certify and/or inviting the inspector watch
himself.
Is the pressure you are talking about the amount of
force to push the anchor in (an axial force) or the
amount of torque to turn the anchor in? With the
hand installed ones, only torque is needed. The
screw pulls itself into the ground.
Rick N6RK
On 7/10/2014 3:24 PM, Brian Amos wrote:
> As for the utilities usually the municipality doesn't inspect their
> installations as they are self regulating. The "screw anchors" ie
> "helical piers" are installed to a certain torque which the software
> tells the installation contractor he must meet. As a soil engineer I
> have many times had to "inspect" the installation where I watch the
> pressure gauge and make sure they make it to the required pressure
> (which they tell me) for each pier and then I have to send a document
> to the owner stating that it complies with the design and put my stamp
> on it. I'm not a big fan of that setup as I don't do the engineering
> but I have to certify that it will hold up. It drives me nuts
> actually. For a residential purpose I would guess that you just tell
> the building official when you will be installing it and they can come
> and watch. That is the only way to really inspect them.
>
> BTW: Is this for supporting the tower? Or is it for the guys? If it's
> for the tower I suspect you will need at least one per leg and it must
> be a large tower to keep them at least 3 screw diameters apart to
> prevent interaction. This type of support provides virtually no
> lateral resistance (especially the square chance bars that have no
> soil contact anywhere but the helix, they are all tension and
> compression, so for guy supports they work great, but not so well for
> a foundation. I suspect that the building official won't care about
> inspecting screws for a guying system. They usually only care about
> the foundation itself.
>
> Brian
> KF7OVD
>
> On Thu, Jul 10, 2014 at 2:21 PM, Jim Lux <jimlux at earthlink.net> wrote:
>> On 7/10/14, 10:29 AM, Richard (Rick) Karlquist wrote:
>>>
>>> Has anyone had experience getting a building permit
>>> for a tower with screw in earth anchors? How does
>>> it get "inspected". There is no empty hole for
>>> the inspector to look at. Do you show him the anchor
>>> before insertion? If you have an authorized AB
>>> Chance installing contractor put in the anchor,
>>> do they issue a certificate that you can show the
>>> inspector? In a sense, this contractor is also
>>> the engineer and building inspector all in one.
>>>
>>
>> could it be more like a material and process inspection?
>> You have the paperwork showing you have the anchor and the mfr's paperwork
>> showing what its properties are.
>> Then you have paperwork showing you did the installation appropriately (e.g.
>> if you used a truck mounted drive, it gives a reading of the torque as it
>> drove it)
>>
>>
>> The only time I've had an "official" inspection of a structure using screw
>> in anchors it was for a temporary installation, and the guy came out, looked
>> at the plans, looked at the erected contraption, verified that what we had
>> built matched the plans, and said "go for it".
>>
>> Granted it was in an area and application where failure would hurt nobody
>> but ourselves.
>>
>> What do utilities do when installing poles with these anchors? I find it
>> hard to believe that the city sends out an inspector to watch them plant
>> every pole and its guys.
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk at contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
------------------------------
Message: 6
Date: Thu, 10 Jul 2014 20:38:46 -0400
From: Mickey Baker <fishflorida at gmail.com>
To: "Richard (Rick) Karlquist" <richard at karlquist.com>
Cc: towertalk at contesting.com
Subject: Re: [TowerTalk] How do bldg inspectors handle screw in earth
anchors?
Message-ID:
<CAOB+T5atUqODHCqW23vx3LdcH62Ess4VaZ+B5rqQDP=K8ngsRg at mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
As always, it depends. Some inspectors are more thorough than others, some
municipalities have more or less stringent standards.
These type anchors are commonly used as tie downs for manufactured
buildings... like mobile homes. Typically there's a site inspection when
the structure is delivered, and the tie downs are part of the package. At
that time, they may be measured or manufacturer's tags inspected and
recorded.
After the structure is placed and the tie downs affixed, they're inspected
at the attach point. The inspector has the option to have one dug up if he
suspects funny business, but I've never seen it happen.
Contractors can get into big trouble for submitting bogus tie down
installations for inspection, not to mention liability issues.
I have a family member who owns several trailer parks, and I've seen this
process repeated many times. If you have a licensed contractor do it, you
are likely to have no problem.
73,
Mickey N4MB
On Jul 10, 2014 1:29 PM, "Richard (Rick) Karlquist" <richard at karlquist.com>
wrote:
> Has anyone had experience getting a building permit
> for a tower with screw in earth anchors? How does
> it get "inspected". There is no empty hole for
> the inspector to look at. Do you show him the anchor
> before insertion? If you have an authorized AB
> Chance installing contractor put in the anchor,
> do they issue a certificate that you can show the
> inspector? In a sense, this contractor is also
> the engineer and building inspector all in one.
>
> Rick N6RK
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
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