Structural Engineering: 2008-12-21

Friday, December 26, 2008

Re: Topped Hollow Core Slab and CMU Wall Construction

From what I recall, the wall is generally done first...but
engineering-wise it should not matter...it would be more of a
construction sequencing decision.

Regards,

Scott
Adrian, MI

On Dec 26, 2008, at 8:59 PM, "Rich Lewis"
<seaint04@lewisengineering.com> wrote:

> I doing a topped hollow core slab with CMU bearing walls. I'm wonde
> ring when the topping is installed. Is it before the next story CMU
> walls are constructed or after? I started detailing it as the topp
> ing is placed prior to the CMU wall construction, but now I'm having
> 2nd thoughts. If the topping is put on first then the next story w
> alls bear on the topping. If the wall goes up first then the CMU be
> ars directly on the plank. I don't think it matters for the strengt
> h of the hollow core slab because the moment is small at the ends an
> d the topping does not help in shear at the ends. It seems to me it
> is a matter of construction sequencing. My guess is that the 2nd f
> loor wall will proceed before the topping is placed.
>
>
>
> Have I made correct assumptions, or should I keep the details with
> the wall bearing on the topping?
>
>
>
> Thanks.
>
>
>
> Rich
>
>

******* ****** ******* ******** ******* ******* ******* ***
* Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
* This email was sent to you via Structural Engineers
* Association of Southern California (SEAOSC) server. To
* subscribe (no fee) or UnSubscribe, please go to:
*
* http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad@seaint.org. Remember, any email you
* send to the list is public domain and may be re-posted
* without your permission. Make sure you visit our web
* site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********

Topped Hollow Core Slab and CMU Wall Construction

I doing a topped hollow core slab with CMU bearing walls. I’m wondering when the topping is installed. Is it before the next story CMU walls are constructed or after? I started detailing it as the topping is placed prior to the CMU wall construction, but now I’m having 2^nd thoughts. If the topping is put on first then the next story walls bear on the topping. If the wall goes up first then the CMU bears directly on the plank. I don’t think it matters for the strength of the hollow core slab because the moment is small at the ends and the topping does not help in shear at the ends. It seems to me it is a matter of construction sequencing. My guess is that the 2^nd floor wall will proceed before the topping is placed.

Have I made correct assumptions, or should I keep the details with the wall bearing on the topping?

Thanks.

Rich

Re: Reindeer live load

Remember, the load is spread across the rails of the sleigh. Also, don't forget the temporary loading, hence Cd = 1.25.

Pretty soon, every roof will be "green," and roof LL will be 100 psf minimum... Yay!

On Wed, Dec 24, 2008 at 7:24 PM, <erik_g@cox.net> wrote:

Holy crap, I just realized that the 40psf for residential roof LL is not
sufficient for Santa. Since he will be loaded down w/ presents and all the
big reindeer and stuff.

I think we should lobby to have the LL changed to 60 psf for roof LL.

******* ****** ******* ******** ******* ******* ******* ***
* Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
* This email was sent to you via Structural Engineers
* Association of Southern California (SEAOSC) server. To
* subscribe (no fee) or UnSubscribe, please go to:
*
* http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad@seaint.org. Remember, any email you
* send to the list is public domain and may be re-posted
* without your permission. Make sure you visit our web
* site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********

--
David Topete, SE

RE: Wood testing

Steve-
Be aware that the properties may vary substantially depending on where the sample was taken. Typically the outer laminations are much higher quality and the tension laminations may differ from the compression laminations in an unbalanced lay-up. Also, the allowable stresses depend on things such as slope of grain and size/location/condition of knots that may not be reflected in the sample.
Regards,
Bill Cain, S.E.
Berkeley, CA

From: spraguehope@hotmail.com
To: seaint@seaint.org
Subject: RE: Wood testing
Date: Fri, 26 Dec 2008 01:17:50 +0000

It depends on what testing you are requiring. Species determination can be determined by the National Forest Products Research Lab.

Regards, Harold Sprague

From: SCHFUN@aol.com
Date: Tue, 23 Dec 2008 12:17:09 -0500
Subject: Wood testing
To: seaint@seaint.org

Does anyone have any recommendations for a testing lab that could determine the strength and deformation properties of a sample of wood from a glu-lam beam? Preferably in or near Southern California.

Thanks,

Steve Helfrich

Helfrich-Associates
30640 Kristin Court
Redlands, CA 92373
909-389-7316
909-389-7326 (FAX)
steve@helfrich-associates.com
www.helfrich-associates.com

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

Send e-mail faster without improving your typing skills. Get your Hotmail® account.

It's the same Hotmail®. If by "same" you mean up to 70% faster. Get your account now.

Thursday, December 25, 2008

RE: Wood testing

It depends on what testing you are requiring. Species determination can be determined by the National Forest Products Research Lab.

Regards, Harold Sprague

From: SCHFUN@aol.com
Date: Tue, 23 Dec 2008 12:17:09 -0500
Subject: Wood testing
To: seaint@seaint.org

Does anyone have any recommendations for a testing lab that could determine the strength and deformation properties of a sample of wood from a glu-lam beam? Preferably in or near Southern California.

Thanks,

Steve Helfrich

Helfrich-Associates
30640 Kristin Court
Redlands, CA 92373
909-389-7316
909-389-7326 (FAX)
steve@helfrich-associates.com
www.helfrich-associates.com

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

Send e-mail faster without improving your typing skills. Get your Hotmail® account.

Reminder: Please Respond to nat's Invitation

nat mohanram wants you to join Yaari!

Is nat your friend?

Yes, nat is my friend! No, nat isn't my friend.

Please respond or nat may think you said no :(

Thanks,
The Yaari Team
____
If you prefer not to receive this email tell us here. If you have any concerns
regarding the content of this message, please email abuse@yaari.com.
Yaari LLC, 358 Angier Ave, Atlanta, GA 30312

YaariSMN433EOF807SVZ986MKT982

Wednesday, December 24, 2008

Reindeer live load

Holy crap, I just realized that the 40psf for residential roof LL is not
sufficient for Santa. Since he will be loaded down w/ presents and all the
big reindeer and stuff.

I think we should lobby to have the LL changed to 60 psf for roof LL.

Re: Seismic Loads in Ceiling

Bill:

Bring your plywood floor diaphragm over to 2' from the bearing walls to blocking between your floor joists. Add sill plates and cripple walls with plywood up to the rafters. transfer the shear to the roof diaphragm through blocking and boundary nailing at the roof plywood.

Hope this helps.

Ray Shreenan SE

----- Original Message -----

From: Bill Allen

To: Seaint

Sent: Monday, December 22, 2008 8:47 AM

Subject: Seismic Loads in Ceiling

Just curious, but I'm interested in how others address transferring the ceiling dead load to lateral force resisting elements in residential construction. I haven't worried about this too much in the past, but I have a project now which consists of a high pitched roof and the owner wants to use the attic space as a floor. Of course, the problem is that I can't connect the floor diaphragm to the top plate of the exterior wall because the roof rafters are in the way. I can't use the ceiling joists in weak axis bending because they do not clear span the structure. Besides, they only run one direction. I'm concerned about using the GWB ceiling as a diaphragm because of what it may do to my R value and that I have a low level of confidence in quality of construction with regards to the installation of drywall fasteners. I have visualized all sorts of complicated (and convoluted) shear transfer details which I would rather not draw nor present to the architect.

TIA,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

Merry Christmas

To all of the engineers out there that participate on this web site: You have made this a great resource particularly with all of the questions regarding the new IBC.

Here's wishing y'all Happy Holidays, peace and prosperity for the coming year.

Ray Shreenan

Re: Happy Holidays

On Dec 24, 2008, at 2:53 PM, Ralph Kratz wrote:

> Apropos of nothing:
>
> "To top it off, we've fallen into a trend of diverting and
> rewarding the best of our collective I.Q.
> to people doing financial engineering rather than real
> engineering. These rocket scientists and engineers were designing
> complex financial instruments to make money out of money -- rather
> than designing cars, phones, computers, teaching tools, Internet
> programs and medical equipment that could improve the lives and
> productivity of millions."
>
> Column "Time To Reboot America" by Thomas L. Friedman, New York
> Times, 12-24-09

This is apropos of everything. Probably the best thing Friedman ever
wrote. We don't need a re-boot, though--we need a new OS.

Christopher Wright P.E. |"They couldn't hit an elephant at
chrisw@skypoint.com | this distance" (last words of Gen.
.......................................| John Sedgwick, Spotsylvania
1864)
http://www.skypoint.com/members/chrisw/

RE: Happy Holidays

Good one. Recently read on SF Chronicle, something like: Rise of MBAs == Decline of Economy

-Suresh Acharya, S.E.

From: Ralph Kratz [mailto:rhkratzse@aol.com]
Sent: Wednesday, December 24, 2008 12:53 PM
To: <seaint@seaint.org>
Cc: seaint@seaint.org
Subject: Re: Happy Holidays

Apropos of nothing:

"To top it off, we've fallen into a trend of diverting and rewarding the best of our collective I.Q.

to people doing financial engineering rather than real engineering. These rocket scientists and engineers were designing complex financial instruments to make money out of money -- rather than designing cars, phones, computers, teaching tools, Internet programs and medical equipment that could improve the lives and productivity of millions."

Column "Time To Reboot America" by Thomas L. Friedman, New York Times, 12-24-09

Happy Holidays!

Ralph Hueston Kratz, S.E.

Richmond CA USA

Sent from my iPhone 3G

On Dec 24, 2008, at 3:28 PM, "David Topete" <d.topete73@gmail.com> wrote:

EVERYBODY- GO HOME!!!!

Spend time with the ones who rarely see you! Happy Holidays and wishes for a better 2009!

On Wed, Dec 24, 2008 at 7:12 AM, <Tom.Hunt@fluor.com> wrote:

Happy Holidays and the best of the New Year to all of our unique Engineering Community.

Thomas Hunt, S.E.
Fluor

------------------------------------------------------------ The information transmitted is intended only for the person  or entity to which it is addressed and may contain  proprietary, business-confidential and/or privileged material.   If you are not the intended recipient of this message you are  hereby notified that any use, review, retransmission, dissemination,  distribution, reproduction or any action taken in reliance upon  this message is prohibited. If you received this in error, please  contact the sender and delete the material from any computer.    Any views expressed in this message are those of the individual  sender and may not necessarily reflect the views of the company.   ------------------------------------------------------------

--
David Topete, SE

Re: Happy Holidays

Warren Buffett recently said that we need more civil engineers than
financial engineers.

Ralph Kratz wrote:
> Apropos of nothing:
>
> "To top it off, we've fallen into a trend of diverting and rewarding
> the best of our collective I.Q.
> to people doing financial engineering rather than real engineering.
> These rocket scientists and engineers were designing complex
> financial instruments to make money out of money -- rather than
> designing cars, phones, computers, teaching tools, Internet programs
> and medical equipment that could improve the lives and productivity of
> millions."
>
> Column "Time To Reboot America" by Thomas L. Friedman, New York Times,
> 12-24-09
>
> Happy Holidays!
>
> Ralph Hueston Kratz, S.E.
> Richmond CA USA
>
> Sent from my iPhone 3G
>
> On Dec 24, 2008, at 3:28 PM, "David Topete" <d.topete73@gmail.com
> <mailto:d.topete73@gmail.com>> wrote:
>
>> EVERYBODY- GO HOME!!!!
>>
>> Spend time with the ones who rarely see you! Happy Holidays and
>> wishes for a better 2009!
>>
>> On Wed, Dec 24, 2008 at 7:12 AM, <Tom.Hunt@fluor.com
>> <mailto:Tom.Hunt@fluor.com>> wrote:
>>
>>
>> Happy Holidays and the best of the New Year to all of our unique
>> Engineering Community.
>>
>> Thomas Hunt, S.E.
>> Fluor
>>
>> ------------------------------------------------------------
>> The information transmitted is intended only for the person
>> or entity to which it is addressed and may contain
>> proprietary, business-confidential and/or privileged material.
>> If you are not the intended recipient of this message you are
>> hereby notified that any use, review, retransmission, dissemination,
>> distribution, reproduction or any action taken in reliance upon
>> this message is prohibited. If you received this in error, please
>> contact the sender and delete the material from any computer.
>>
>> Any views expressed in this message are those of the individual
>> sender and may not necessarily reflect the views of the company.
>> ------------------------------------------------------------
>>
>>
>>
>>
>>
>> --
>> David Topete, SE
> =

Re: Happy Holidays

Apropos of nothing:

"To top it off, we've fallen into a trend of diverting and rewarding the best of our collective I.Q.

Column "Time To Reboot America" by Thomas L. Friedman, New York Times, 12-24-09

Happy Holidays!

Ralph Hueston Kratz, S.E.

Richmond CA USA

Sent from my iPhone 3G

On Dec 24, 2008, at 3:28 PM, "David Topete" <d.topete73@gmail.com> wrote:

EVERYBODY- GO HOME!!!!

Spend time with the ones who rarely see you! Happy Holidays and wishes for a better 2009!

On Wed, Dec 24, 2008 at 7:12 AM, <Tom.Hunt@fluor.com> wrote:

Happy Holidays and the best of the New Year to all of our unique Engineering Community.

Thomas Hunt, S.E.
Fluor

------------------------------------------------------------ The information transmitted is intended only for the person  or entity to which it is addressed and may contain  proprietary, business-confidential and/or privileged material.   If you are not the intended recipient of this message you are  hereby notified that any use, review, retransmission, dissemination,  distribution, reproduction or any action taken in reliance upon  this message is prohibited. If you received this in error, please  contact the sender and delete the material from any computer.    Any views expressed in this message are those of the individual  sender and may not necessarily reflect the views of the company.   ------------------------------------------------------------

--
David Topete, SE

Re: Happy Holidays

EVERYBODY- GO HOME!!!!

Spend time with the ones who rarely see you! Happy Holidays and wishes for a better 2009!

On Wed, Dec 24, 2008 at 7:12 AM, <Tom.Hunt@fluor.com> wrote:

Happy Holidays and the best of the New Year to all of our unique Engineering Community.

Thomas Hunt, S.E.
Fluor

------------------------------------------------------------ The information transmitted is intended only for the person  or entity to which it is addressed and may contain  proprietary, business-confidential and/or privileged material.   If you are not the intended recipient of this message you are  hereby notified that any use, review, retransmission, dissemination,  distribution, reproduction or any action taken in reliance upon  this message is prohibited. If you received this in error, please  contact the sender and delete the material from any computer.    Any views expressed in this message are those of the individual  sender and may not necessarily reflect the views of the company.   ------------------------------------------------------------

--
David Topete, SE

re: Merry Christmas & Happy 2009

I wish every single one of you, our valuable SEAINT listserve contributors, a very Merry Christmas, a peaceful and prosperous 2009.

Thanks to all of you for your valuable contributions.

May God Bless structural engineers...

Regards
Casey (Khashayar) Hemmatyar, SE
Private email k_AT_hemmatyar.com

List members:

I wish all of us peace and good karma for 2009.

Cheers,

David L. Fisher SE PE

Fisher and Partners - Cayman

372 West Ontario Chicago 60610

75 Fort Street Georgetown Grand Cayman BWI

319 A Street Boston 02210

312.573.1701

312.573.1726 facsimile

312.622.0409 mobile

www.fpse.com

Best Wishes

Fellow engineers,

I wish you all a Merry Christmas and a Happy New Year.

For those who do not celebrate Christmas I wish you a happy, healthy, and prosperous year for 2009.

I am painfully aware that some of you, particularly the younger ones, may be facing hard times over the next several months. I hope and pray that these difficult times will be short lived. One small piece of advice I can offer is "Don't despair; even this shall pass if we persevere." Remember, tough times don't last; tough people do. Just don't give up!

My very best regards to all of you,

H. Daryl Richardson,

Calgary, Canada

merry christmas

I wish all of you a merry christmas and a good start into a successful new year 2009.

Best regards

Alfred Mueller

Happy Holidays

Happy Holidays and the best of the New Year to all of our unique Engineering Community.

Thomas Hunt, S.E.
Fluor

------------------------------------------------------------ The information transmitted is intended only for the person  or entity to which it is addressed and may contain  proprietary, business-confidential and/or privileged material.   If you are not the intended recipient of this message you are  hereby notified that any use, review, retransmission, dissemination,  distribution, reproduction or any action taken in reliance upon  this message is prohibited. If you received this in error, please  contact the sender and delete the material from any computer.    Any views expressed in this message are those of the individual  sender and may not necessarily reflect the views of the company.   ------------------------------------------------------------

Tuesday, December 23, 2008

Christmas Greetings!

"But he was pierced for our offenses, crushed for our sins, Upon him was the chastisement that makes us whole, by his stripes we were healed." Is 53:5. The reason for the season. Have a very blessed Christmas.

Jeff

RE: ASCE 7-05 and IBC 06

Phuong-

I can't give you a definite answer but I can add that my experience is
that there is no difference in any location I have looked up inside
California. If the building official wants that parameter selected on
the drag down menu when you run the program, just do it and it won't
change your design in the port area... I am 99.99% certain. The IBC
2006, CBC 2007 and ASCE-7-05 all print he same seismic map that has
identical references to FEMA documents and USGS survey so I would be
surprised if they are different for the continental US. Obviously the
map is too small to use and I have never been able to find a obvious
reference in the code that identifies which pull down to select in the
electronic program.

I am hoping someone on the list can chime in and explain the difference
or point to the reference as I too am curious.

I rarely use the program to generate parameters as most of my projects
have soils reports which provide the info but I do use it occasionally
and also like to verify the soils report.

Obviously once you have these parameters plug them into your governing
code which I believe is the LB city which is based on CBC with additions
and CBC is based on IBC, etc, etc and all reference ASCE 7-05.

Good luck,

Donny Harris, SE
Los Angeles

List,
My question may be quite basic, but I would appreciate very much your
opini=
on. Is there any discrepancy/ies between of SDs and SD1 values from IBC
200=
6 vs ASCE 7-05 when you input the same Latitude and Longitude into the
Seis=
mic Hazard Curve and Uniform Hazard Response Spectra? (program
downloaded f=
rom http://earthquake.usgs.gov/research/hazmaps/design/). I checked many
lo=
cations using the IBC 2006 pull down menu, and then ASCE 7 Standard, and
fo=
und the values for SDs and SD1 are identical respectively.
I was advised by Building Department that only ASCE 7-05 is accepted
though=
. Does it make any difference if the site is located in California? Any
hin=
ts is greatly appreciated.

Phuong Nguyen
CM/ Construction Division
Port of Los Angeles
(310) 732-3537

Re: Wood testing

Steve

I have the info at my office....I will not be back till Monday. Alan is the first name.

Located in Orange county. West coast testing or something like that.

Joe Venuti
Johnson & Nielsen Associates
Palm Springs, CA

In a message dated 12/23/2008 9:16:07 A.M. Pacific Standard Time, SCHFUN@aol.com writes:

Does anyone have any recommendations for a testing lab that could determine the strength and deformation properties of a sample of wood from a glu-lam beam? Preferably in or near Southern California.

Thanks,

Steve Helfrich

Helfrich-Associates
30640 Kristin Court
Redlands, CA 92373
909-389-7316
909-389-7326 (FAX)
steve@helfrich-associates.com
www.helfrich-associates.com

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

RE: Radiant Floor System on Plywood Subfloor

Further information on the subject is provided below. The APA was also kind enough to provide me with Report 132 - Plywood in Hostile Environments for which I do not see any copyright notice and would thus be willing to share.

Michel

Please review the attached document which provides information regarding plywood exposed to extreme temperatures. If your fluid temperatures are below 180 degrees F, there should be no issues.

Regards,

Ray Clark

Product Support Specialist

Wood Products Support Help Desk

APA

Southern Forest Products Association

Structural Insulated Panel Association

253-620-7400 (phone)

253-565-7265 (fax)

ray.clark@apawood.org

www.APAwood.org

www.SouthernPine.com

www.SIPS.org

Wood testing

Does anyone have any recommendations for a testing lab that could determine the strength and deformation properties of a sample of wood from a glu-lam beam? Preferably in or near Southern California.

Thanks,

Steve Helfrich

Helfrich-Associates
30640 Kristin Court
Redlands, CA 92373
909-389-7316
909-389-7326 (FAX)
steve@helfrich-associates.com
www.helfrich-associates.com

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

RE: Radiant Floor System on Plywood Subfloor

Hi Jeff,

The tubes are sandwiched between plywood layers. The APA refered me to the Radiant Panel Association and a link with info on the subject: www.radiantpanelassociation.org/i4a/pages/index.cfm?pageid=117.

Regards,

Michel

-----Original Message-----
From: Jeff Smith [mailto:jeffsmith7@comcast.net]
Sent: Monday, December 22, 2008 7:23 PM
To: seaint@seaint.org
Subject: RE: Radiant Floor System on Plywood Subfloor

I agree you should see what the APA has to say.

I am still unclear, are the radiant tubes in a gypcrete topping on top of the subfloor, are they in a warmboard type subfloor, subfloor plus tubes/plywood sandwich, or a staple-up type radiant, what is the finish floor?

I would think that a manufacturer of a radiant flooring system would provide strict specifications for the entire assembly. Some systems can deliver water at up to 140 degrees F. Dry installtions require higher water tempurature. It is my understanding that a 140 degee water tempurature will not adversley effect the plywood subfloor, but it may have an effect on the finish wood flooring or mastic type adhesives. Big, fast temperature changes in humid conditions can effect the finish wood flooring. Therefore there may be limitations on the type of wood, plank size or you may need an engineered laminated wood flooring that is made for such a use. Another issue with tubes directly under finish wood flooring is that it does not distribute the heat as well and may have localized hot spots.

From: Michel Blangy [mailto:mblangy@satco-inc.com]
Sent: Monday, December 22, 2008 2:16 PM
To: seaint@seaint.org
Subject: RE: Radiant Floor System on Plywood Subfloor

oops...I'm concerned with temperature. Sorry.

-----Original Message-----
From: David Topete [mailto:d.topete73@gmail.com]
Sent: Monday, December 22, 2008 1:24 PM
To: seaint@seaint.org
Subject: Re: Radiant Floor System on Plywood Subfloor

"What is the maximum allowable set for water?" I am unclear about what you're asking... Are you asking what to add to the uniform DL of the floor? it wouldn't be much... I'd use 8-10 psf per inch of gypcrete topping that the radiant system is encased in.

On Mon, Dec 22, 2008 at 1:00 PM, Michel Blangy <mblangy@satco-inc.com> wrote:

Seasons greetings list,

I think this is on-topic...

For a radiant floor system with tubes installed in direct contact with the
plywood subfloor, what is the maximum allowable set for water?

I have an inquiry in to the APA, but thought I'd try here also.

Regards,

Michel Blangy

******* ****** ******* ******** ******* ******* ******* ***
* Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
* This email was sent to you via Structural Engineers
* Association of Southern California (SEAOSC) server. To
* subscribe (no fee) or UnSubscribe, please go to:
*
* http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad@seaint.org. Remember, any email you
* send to the list is public domain and may be re-posted
* without your permission. Make sure you visit our web
* site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********

--
David Topete, SE

Monday, December 22, 2008

RE: Radiant Floor System on Plywood Subfloor

I agree you should see what the APA has to say.

I am still unclear, are the radiant tubes in a gypcrete topping on top of the subfloor, are they in a warmboard type subfloor, subfloor plus tubes/plywood sandwich, or a staple-up type radiant, what is the finish floor?

I would think that a manufacturer of a radiant flooring system would provide strict specifications for the entire assembly. Some systems can deliver water at up to 140 degrees F. Dry installtions require higher water tempurature. It is my understanding that a 140 degee water tempurature will not adversley effect the plywood subfloor, but it may have an effect on the finish wood flooring or mastic type adhesives. Big, fast temperature changes in humid conditions can effect the finish wood flooring. Therefore there may be limitations on the type of wood, plank size or you may need an engineered laminated wood flooring that is made for such a use. Another issue with tubes directly under finish wood flooring is that it does not distribute the heat as well and may have localized hot spots.

From: Michel Blangy [mailto:mblangy@satco-inc.com]
Sent: Monday, December 22, 2008 2:16 PM
To: seaint@seaint.org
Subject: RE: Radiant Floor System on Plywood Subfloor

oops...I'm concerned with temperature. Sorry.

-----Original Message-----
From: David Topete [mailto:d.topete73@gmail.com]
Sent: Monday, December 22, 2008 1:24 PM
To: seaint@seaint.org
Subject: Re: Radiant Floor System on Plywood Subfloor

"What is the maximum allowable set for water?" I am unclear about what you're asking... Are you asking what to add to the uniform DL of the floor? it wouldn't be much... I'd use 8-10 psf per inch of gypcrete topping that the radiant system is encased in.

On Mon, Dec 22, 2008 at 1:00 PM, Michel Blangy <mblangy@satco-inc.com> wrote:

Seasons greetings list,

I think this is on-topic...

For a radiant floor system with tubes installed in direct contact with the
plywood subfloor, what is the maximum allowable set for water?

I have an inquiry in to the APA, but thought I'd try here also.

Regards,

Michel Blangy

******* ****** ******* ******** ******* ******* ******* ***
* Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
* This email was sent to you via Structural Engineers
* Association of Southern California (SEAOSC) server. To
* subscribe (no fee) or UnSubscribe, please go to:
*
* http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad@seaint.org. Remember, any email you
* send to the list is public domain and may be re-posted
* without your permission. Make sure you visit our web
* site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********

--
David Topete, SE

RE: ASCE 7-05 and IBC 06

Nguyen,

If you were writing IBC:2006 with simplified methods then you would look for some more detailed and complete method to calibrate against: that would most likely be ASCE7-05.

As such should have some familiarity with how the two relate. Then argue that complying with IBC:2006 is indirectly complying with ASCE7-05.

I don’t have IBC:2006 or familiar with seismic, but the relationship between the two codes, should be clear from values of parameters used. For example relatively easy to transform ASCE7-05 wind into IBC:2003 simplified wind. Seismic should be similar.

Usually when a building official requests use of a more detailed code, it is because they don’t want you to skip certain details and issues missing from the simplified methods. If you can only use the simplified method then there may be something in the more detailed code which you are unaware off: and it may be important.

Your task therefore is to explicitly dismiss those issues before adopting the use of the simplified method: IBC:2006. If you can do that then building department shouldn’t have any problems with your submission.

Regards

Conrad Harrison

B.Tech (mfg & mech), MIIE, gradTIEAust

mailto:sch.tectonic@bigpond.com

Adelaide

South Australia

ASCE 7-05 and IBC 06

List,

My question may be quite basic, but I would appreciate very much your opinion. Is there any discrepancy/ies between of SDs and SD1 values from IBC 2006 vs ASCE 7-05 when you input the same Latitude and Longitude into the Seismic Hazard Curve and Uniform Hazard Response Spectra? (program downloaded from http://earthquake.usgs.gov/research/hazmaps/design/). I checked many locations using the IBC 2006 pull down menu, and then ASCE 7 Standard, and found the values for SDs and SD1 are identical respectively.

I was advised by Building Department that only ASCE 7-05 is accepted though. Does it make any difference if the site is located in California? Any hints is greatly appreciated.

Phuong Nguyen

CM/ Construction Division

Port of Los Angeles

(310) 732-3537

-----------------------------------Confidentiality Notice--------------------------------------------------
This electronic message transmission contains information from the Port of Los Angeles, which may be confidential. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the content of this information is prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the original message and any attachment without reading or saving in any manner.

RE: Radiant Floor System on Plywood Subfloor

oops...I'm concerned with temperature. Sorry.

-----Original Message-----
From: David Topete [mailto:d.topete73@gmail.com]
Sent: Monday, December 22, 2008 1:24 PM
To: seaint@seaint.org
Subject: Re: Radiant Floor System on Plywood Subfloor

"What is the maximum allowable set for water?" I am unclear about what you're asking... Are you asking what to add to the uniform DL of the floor? it wouldn't be much... I'd use 8-10 psf per inch of gypcrete topping that the radiant system is encased in.

On Mon, Dec 22, 2008 at 1:00 PM, Michel Blangy <mblangy@satco-inc.com> wrote:

Seasons greetings list,

I think this is on-topic...

For a radiant floor system with tubes installed in direct contact with the
plywood subfloor, what is the maximum allowable set for water?

I have an inquiry in to the APA, but thought I'd try here also.

Regards,

Michel Blangy

******* ****** ******* ******** ******* ******* ******* ***
* Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
* This email was sent to you via Structural Engineers
* Association of Southern California (SEAOSC) server. To
* subscribe (no fee) or UnSubscribe, please go to:
*
* http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad@seaint.org. Remember, any email you
* send to the list is public domain and may be re-posted
* without your permission. Make sure you visit our web
* site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********

--
David Topete, SE

Re: Radiant Floor System on Plywood Subfloor

"What is the maximum allowable set for water?" I am unclear about what you're asking... Are you asking what to add to the uniform DL of the floor? it wouldn't be much... I'd use 8-10 psf per inch of gypcrete topping that the radiant system is encased in.

On Mon, Dec 22, 2008 at 1:00 PM, Michel Blangy <mblangy@satco-inc.com> wrote:

Seasons greetings list,

I think this is on-topic...

For a radiant floor system with tubes installed in direct contact with the
plywood subfloor, what is the maximum allowable set for water?

I have an inquiry in to the APA, but thought I'd try here also.

Regards,

Michel Blangy

******* ****** ******* ******** ******* ******* ******* ***
* Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
* This email was sent to you via Structural Engineers
* Association of Southern California (SEAOSC) server. To
* subscribe (no fee) or UnSubscribe, please go to:
*
* http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad@seaint.org. Remember, any email you
* send to the list is public domain and may be re-posted
* without your permission. Make sure you visit our web
* site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********

--
David Topete, SE

Radiant Floor System on Plywood Subfloor

Seasons greetings list,

I think this is on-topic...

For a radiant floor system with tubes installed in direct contact with the
plywood subfloor, what is the maximum allowable set for water?

I have an inquiry in to the APA, but thought I'd try here also.

Regards,

Michel Blangy

RE: Building Code and Other National Standards

As Tom noted, there are clear provisions for alternate standards for seismic design of tanks. But for general code provisions, you probably need to apply 2006 IBC Section 104.11, which allows the Building Official to accept alternate methods of design and construction. For non-building structures such as tanks, I would expect the Building Official to accept other common industry standards as long as design loads are reasonably consistent with the IBC loads (e.g., similar wind design parameters).

Bill Sherman

CH2M HILL / DEN

720-286-2792

From: Tom.Hunt@fluor.com [mailto:Tom.Hunt@fluor.com]
Sent: Monday, December 22, 2008 12:22 PM
To: seaint@seaint.org
Subject: Re: Building Code and Other National Standards

Paul,

You may find what you are looking for in ASCE 7 Section 15.4.1 - 1 (c) and for your specific case look at ASCE 7 Section 15.7.7, "Water Storage and Water Treatment Tanks and Vessels".

Thomas Hunt, S.E.
Fluor

"Paul Blomberg" <paul.blomberg@gmail.com>
12/22/2008 11:10 AM
Please respond to seaint

To
seaint <seaint@seaint.org>

cc

Subject
Building Code and Other National Standards

I'm looking for the area in the IBC which 'allows' the use of other approved national standards. I have a spec that calls out the IBC and provides the site criteria (wind design criteria, seismic design criteria, ...) A vendor is supplying an AWWA steel tank including foundation. I thought I remembered a section of the code that said that directed you to the industry specific codes when applicable.

Anyone have an idea where this exists in the code?

Paul.
Phoenix, AZ
------------------------------------------------------------ The information transmitted is intended only for the person  or entity to which it is addressed and may contain  proprietary, business-confidential and/or privileged material.   If you are not the intended recipient of this message you are  hereby notified that any use, review, retransmission, dissemination,  distribution, reproduction or any action taken in reliance upon  this message is prohibited. If you received this in error, please  contact the sender and delete the material from any computer.    Any views expressed in this message are those of the individual  sender and may not necessarily reflect the views of the company.   ------------------------------------------------------------ 

Re: Building Code and Other National Standards

Paul,

You may find what you are looking for in ASCE 7 Section 15.4.1 - 1 (c) and for your specific case look at ASCE 7 Section 15.7.7, "Water Storage and Water Treatment Tanks and Vessels".

Thomas Hunt, S.E.
Fluor

"Paul Blomberg" <paul.blomberg@gmail.com>
12/22/2008 11:10 AM
Please respond to seaint

To	seaint <seaint@seaint.org>
cc
Subject	Building Code and Other National Standards

I'm looking for the area in the IBC which 'allows' the use of other approved national standards. I have a spec that calls out the IBC and provides the site criteria (wind design criteria, seismic design criteria, ...) A vendor is supplying an AWWA steel tank including foundation. I thought I remembered a section of the code that said that directed you to the industry specific codes when applicable.

Anyone have an idea where this exists in the code?

Paul.
Phoenix, AZ

------------------------------------------------------------ The information transmitted is intended only for the person  or entity to which it is addressed and may contain  proprietary, business-confidential and/or privileged material.   If you are not the intended recipient of this message you are  hereby notified that any use, review, retransmission, dissemination,  distribution, reproduction or any action taken in reliance upon  this message is prohibited. If you received this in error, please  contact the sender and delete the material from any computer.    Any views expressed in this message are those of the individual  sender and may not necessarily reflect the views of the company.   ------------------------------------------------------------

Building Code and Other National Standards

Anyone have an idea where this exists in the code?

Paul.

Phoenix, AZ

RE: Seismic Loads in Ceiling

Bill,

How about sheathing the loft/attic floor with plywood to say 24" short of the exterior wall, and then

sheathing the remaining 24" strip on the underside of the joists

Tarek Mokhtar, SE

Laguna Beach, Ca

Sure, but it's another layer of sheathing.

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 * F(949) 209-2509

-----Original Message-----
From: Jason Christensen [mailto:jason@wcaeng.com]
Sent: Monday, December 22, 2008 10:03 AM
To: seaint@seaint.org
Subject: RE: Seismic Loads in Ceiling

Could you use a 3/8 sheathing under the GWB ceiling?

Jason

WCA Structural Engineering, Inc.

-----Original Message-----
From: Jnapd@aol.com [mailto:Jnapd@aol.com]
Sent: Monday, December 22, 2008 8:53 AM
To: seaint@seaint.org
Subject: Re: Seismic Loads in Ceiling

Bill

Can you treat this area as a loft ?

In a message dated 12/22/2008 8:48:20 A.M. Pacific Standard Time, t.w.allen@cox.net writes:

Just curious, but I'm interested in how others address transferring the ceiling dead load to lateral force resisting elements in residential construction. I haven't worried about this too much in the past, but I have a project now which consists of a high pitched roof and the owner wants to use the attic space as a floor. Of course, the problem is that I can't connect the floor diaphragm to the top plate of the exterior wall because the roof rafters are in the way. I can't use the ceiling joists in weak axis bending because they do not clear span the structure. Besides, they only run one direction. I'm concerned about using the GWB ceiling as a diaphragm because of what it may do to my R value and that I have a low level of confidence in quality of construction with regards to the installation of drywall fasteners. I have visualized all sorts of complicated (and convoluted) shear transfer details which I would rather not draw nor present to the architect.

TIA,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 * F(949) 209-2509

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

--

RE: Seismic Loads in Ceiling

If the ceiling joist are not exposed (top side) and if it is permitted in your area, you could use Simpson coil straps and create X-bracing to transfer the load.

Jason

WCA Structural Engineering, Inc.

From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Monday, December 22, 2008 11:08 AM
To: seaint@seaint.org
Subject: RE: Seismic Loads in Ceiling

Sure, but it's another layer of sheathing.

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

-----Original Message-----
From: Jason Christensen [mailto:jason@wcaeng.com]
Sent: Monday, December 22, 2008 10:03 AM
To: seaint@seaint.org
Subject: RE: Seismic Loads in Ceiling

Could you use a 3/8 sheathing under the GWB ceiling?

Jason

WCA Structural Engineering, Inc.

-----Original Message-----
From: Jnapd@aol.com [mailto:Jnapd@aol.com]
Sent: Monday, December 22, 2008 8:53 AM
To: seaint@seaint.org
Subject: Re: Seismic Loads in Ceiling

Bill

Can you treat this area as a loft ?

In a message dated 12/22/2008 8:48:20 A.M. Pacific Standard Time, t.w.allen@cox.net writes:

Just curious, but I'm interested in how others address transferring the ceiling dead load to lateral force resisting elements in residential construction. I haven't worried about this too much in the past, but I have a project now which consists of a high pitched roof and the owner wants to use the attic space as a floor. Of course, the problem is that I can't connect the floor diaphragm to the top plate of the exterior wall because the roof rafters are in the way. I can't use the ceiling joists in weak axis bending because they do not clear span the structure. Besides, they only run one direction. I'm concerned about using the GWB ceiling as a diaphragm because of what it may do to my R value and that I have a low level of confidence in quality of construction with regards to the installation of drywall fasteners. I have visualized all sorts of complicated (and convoluted) shear transfer details which I would rather not draw nor present to the architect.

TIA,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

RE: Seismic Loads in Ceiling

Could you use a sanded plywood without the GWB, then mud, tape and texture. Not sure if you can mud and tape plywood though.

Jason

WCA Structural Engineering, Inc.

From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Monday, December 22, 2008 11:08 AM
To: seaint@seaint.org
Subject: RE: Seismic Loads in Ceiling

Sure, but it's another layer of sheathing.

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

-----Original Message-----
From: Jason Christensen [mailto:jason@wcaeng.com]
Sent: Monday, December 22, 2008 10:03 AM
To: seaint@seaint.org
Subject: RE: Seismic Loads in Ceiling

Could you use a 3/8 sheathing under the GWB ceiling?

Jason

WCA Structural Engineering, Inc.

-----Original Message-----
From: Jnapd@aol.com [mailto:Jnapd@aol.com]
Sent: Monday, December 22, 2008 8:53 AM
To: seaint@seaint.org
Subject: Re: Seismic Loads in Ceiling

Bill

Can you treat this area as a loft ?

In a message dated 12/22/2008 8:48:20 A.M. Pacific Standard Time, t.w.allen@cox.net writes:

Just curious, but I'm interested in how others address transferring the ceiling dead load to lateral force resisting elements in residential construction. I haven't worried about this too much in the past, but I have a project now which consists of a high pitched roof and the owner wants to use the attic space as a floor. Of course, the problem is that I can't connect the floor diaphragm to the top plate of the exterior wall because the roof rafters are in the way. I can't use the ceiling joists in weak axis bending because they do not clear span the structure. Besides, they only run one direction. I'm concerned about using the GWB ceiling as a diaphragm because of what it may do to my R value and that I have a low level of confidence in quality of construction with regards to the installation of drywall fasteners. I have visualized all sorts of complicated (and convoluted) shear transfer details which I would rather not draw nor present to the architect.

TIA,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.

One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now.