Which Tornado Saferoom is Right for You?

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Image courtesy of FLASH.

There certainly seems to be increased awareness of the potential for damage and injury from tornadoes these days. Recent information published by the Federal Emergency Management Agency (FEMA) and the Federal Alliance for Safe Homes (FLASH) help explain that. This increased awareness has led to a growing interest in tornado shelters for protection of life and property.

This FEMA graphic shows that most areas of the United States have been affected by a tornado at some point since 1996, and many have been affected by one or more strong tornadoes (EF3 or greater).

Figure 1 - Tornado activity by county: 1996-2013

Figure 1 – Tornado activity by county: 1996-2013

Living in North Texas near the Simpson Strong-Tie manufacturing plant in McKinney, Texas, I know all too well the sinking feeling of hearing the tornado sirens and turning on the TV to find you are under a tornado watch. FLASH recently published a graphic developed by the National Weather Service that shows the large number of U.S. counties that have been under a tornado watch between 2003-2014, and the high number of warnings that some counties experienced.

Figure 2 -  Annual average number of hours under NWS/SPC tornado watches (2003-2014)

Figure 2 – Annual average number of hours under NWS/SPC tornado watches (2003-2014)

Other than moving to an area that has fewer tornadoes, one of the best ways to protect your family and at least have more peace of mind during tornado season is to have a tornado shelter or safe room. These structures are designed and tested to resist the highest winds that meteorologists and engineers believe occur at ground level during a tornado and the debris that is contained in tornado winds.

Tornado shelters can be either pre-fabricated and installed by a specialty shelter manufacturer, or can be site-built from a designed plan or pre-engineered plan. A good source for information on pre-fabricated shelters is the National Storm Shelter Association, a self-policing organization that has strict requirements for the design, testing and installation of its members’ shelters.

FEMA publishes a document, P-320, Taking Shelter from the Storm, that provides good information on safe rooms in general, as well as several pre-engineered plans for tornado safe rooms.

To highlight the different types of safe rooms covered by FEMA P-320, FEMA, FLASH and the Portland Cement Association (PCA) sponsored an exhibit at January’s International Builder’s Show. The exhibit was called the “Home Safe Home Tornado Saferoom Showcase.” It featured six different types of saferooms that builders could incorporate into the homes they build. Simpson Strong-Tie and the American Wood Council collaborated to build a wood frame with steel sheathing safe room meeting the FEMA P-320 plans. Other safe rooms shown at the exhibit included pre-cast concrete and pre-manufactured steel shelters manufactured by NSSA members, and reinforced CMU, ICF cast-in-place concrete and aluminum formed cast-in-place concrete built to FEMA P-320 plans.

Figure 4 - Home Safe Home Tornado Saferoom Showcase

Figure 4 – Home Safe Home Tornado Saferoom Showcase

Simpson Strong-Tie staff in McKinney, Texas, constructed the wood frame/steel sheathing safe room in panels and shipped it to the show. It was built from locally sourced lumber, readily available fasteners and connectors and sheets of 16 ga. steel (which we happen to keep here at the factory). It had cut-away sheathing at the corners to show the three layers of sheathing needed. Our message to builders was that this type of shelter would be the easiest for their framers to build on their sites.

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Figure 5: Holdowns and plate anchorage

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Figure 6: Roof-to-wall connections

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Figure 7: A visitor examines our tested door, a vital component of any shelter. This one was furnished by CECO Doors.

The sponsors of the exhibit took advantage of the variety of safe rooms in one place to film a video series, “Which Tornado Safe Room is Right for You?The videos are posted at the FLASH StrongHomes channel on YouTube. The series provides comparative information on cast-in-place, concrete block masonry, insulated concrete forms, precast concrete and wood-frame safe rooms, with the goal of helping consumers to better understand their tornado safe room options.

“Today’s marketplace offers an unprecedented range of high-performing, affordable options to save lives and preserve peace of mind for the millions of families in the path of severe weather,” said FLASH President and CEO Leslie Chapman-Henderson. “These videos will help families understand their options for a properly built safe room that will deliver life safety when it counts.”

FLASH released the videos earlier this month as part America’s PrepareAthon!, a grassroots campaign to increase community emergency preparedness and resilience through hazard-specific drills, group discussions and exercises. The overall goal of the program is to get individuals to understand which disasters could happen in their community, know what to do to be safe and mitigate damage from those disasters, take action to increase their preparedness, and go one step farther by participating in resilience planning for their community. Currently, the program focuses on preparing for the disasters of tornadoes, hurricanes, floods, wildfires, earthquakes and winter storms.

Do you know what the risk of disasters is in your community? If you are subject to tornado risk, would you like to build your own safe room, have one built to pre-engineered plans or buy one from a reputable manufacturer? Let us know in the comments below.

New Treatment of Shear Wall Aspect Ratios in the 2015 SDPWS

This post was co-written by Simpson Engineer Randy Shackelford and AWC Engineer Phil Line.

The 2015 International Building Code references a newly updated 2015 Edition of the American Wood Council Special Design Provisions for Wind and Seismic standard (SDPWS). The updated SDPWS contains new provisions for design of high aspect ratio shear walls. For wood structural panels shear walls, the term high aspect ratio is considered to apply to walls with an aspect ratio greater than 2:1.

Figure 1. SDPWS 2008 Table 4.3.4 and illustration of shear wall with height, h and length, bs

In the 2015 SDPWS, reduction factors for high aspect ratio shear walls are no longer contained in the footnotes to Table 4.3.4 (See Figure 2). Instead, these factors are included in new provisions accounting for the reduced strength and stiffness of high aspect ratio shear walls.

Figure 2.  SDPWS 2015 Table 4.3.4

Figure 2. SDPWS 2015 Table 4.3.4

Deflection Compatibility – Calculation Method

New Section 4.3.3.4.1 states that “Shear distribution to individual shear walls in a shear wall line shall provide the same calculated deflection, δsw, in each shear wall.” Using this equal deflection calculation method for distribution of shear, the unit shear assigned to each shear wall within a shear wall line varies based on its stiffness relative to that of the other shear walls in the shear wall line. Thus, a shear wall having relatively low stiffness, as is the case of a high aspect ratio shear wall within a shear wall line containing a longer shear wall, is assigned a reduced unit shear (see Figure 3).

Figure 3. Illustration of deflection compatibility

 

In addition, Section 4.3.4.2 contains a new aspect ratio factor, 1.25 – 0.125h/bs, that specifically accounts for the reduced unit shear capacity of high aspect ratio shear walls. The strength reduction varies linearly from 1.00 for a 2:1 aspect ratio shear wall to 0.81 for a 3.5:1 aspect ratio shear wall. Notably, this strength reduction applies for shear walls resisting either seismic forces or wind forces. For both wind and seismic, the controlling unit shear capacity is the smaller of the values from strength criteria of 4.3.4.2 or deflection compatibility criteria or 4.3.3.4.1.

Deflection Compatibility – 2bs/h Adjustment Factor Method

The 2bs/h factor, previously addressed by footnote 1 of Table 4.3.4, is now an alternative to the equal deflection calculation method of 4.3.3.4.1 and applies to shear walls resisting either wind or seismic forces. This adjustment factor method allows the designer to distribute shear in proportion to shear wall strength provided that shear walls with high aspect ratio have strength adjusted by the 2bs/h factor. The strength reduction varies linearly from 1.00 for 2:1 aspect ratio shear walls to 0.57 for 3.5:1 aspect ratio shear walls. This adjustment factor method provides roughly similar designs to the equal deflection calculation method for a shear wall line comprised of a 1:1 aspect ratio wall segment in combination with a high aspect ratio shear wall segment.

In prior editions of SDPWS, a common misunderstanding was that the 2bs/h factor represented an actual reduction in unit shear capacity for high aspect ratio shear walls as opposed to a reduction factor to account for stiffness compatibility. The actual reduction in unit shear capacity of high aspect ratio shear walls is represented by the factor, 1.25 – 0.125h/bs, as noted previously. The 2bs/h factor is the more severe of the two factors and is not applied simultaneously with the 1.25-0.125h/bs factor.

What are the major implications for design?

  • For seismic design, the 2bs/h factor method continues unchanged, but is presented as an alternative to the equal deflection method in 4.3.3.4.1 for providing deflection compatibility. The equal deflection calculation method can produce both more and less efficient designs that may result from the 2bs/h factor method depending on the relative stiffness of shear walls in the wall line. For example, design unit shear for shear wall lines comprised entirely of 3.5:1 aspect ratio shear walls can be as much as 40% greater (i.e. 0.81/0.57=1.42) than prior editions if not limited by seismic drift criteria.
  • For wind design, high aspect ratio shear wall factors apply for the first time. For shear walls with 3.5:1 aspect ratio, unit shear capacity is reduced to not more than 81% of that used in prior editions. The actual reduction will vary by actual method used to account for deflection compatibility.
  • The equal deflection calculation method is sensitive to many factors in the shear wall deflection calculation including hold-down slip, sheathing type and nailing, and framing moisture content. The familiar 2bs/h factor method for deflection compatibility is less sensitive to factors that affect shear wall deflection calculations and in many cases will produce more efficient designs.

As the 2015 International Building Code is adopted in various jurisdictions, designers will need to be aware of these new requirements for design of high aspect ratio shear walls. The 2015 SDPWS also contains other important revisions that designers should pay attention to. The American Wood Council provides a read-only version of the standard on their website that is available free of charge.

Please contribute your thoughts to these new requirements in the comments below.

Here Come 2015 IBC Changes!

All of us here at Simpson Strong-Tie hope you had a happy and successful 2014. It seems that the folks at the International Code Council had a good year. True to their plan, the 2015 editions of the International Codes were published during the summer so that they are ready for adoption in 2015.

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SE blog 2Simpson Strong-Tie was tracking a number of issues during the development of the 2015 International Building Code and International Residential Code. Here is a summary of some of the significant changes that users will see in the 2015 International Building Code (IBC).

One significant change affecting Simpson Strong-Tie was the removal of the requirements for evaluation of joist hangers and similar devices from Chapter 17, and the revision of Sections 2303.5 and 2304.10.3 to reference ASTM D 7147 as the test standard for joist hangers.

Since the primary reference standard for design in Chapter 16, ASCE 7-10 has not changed; there were not a lot of significant changes in that chapter. The definitions of “Diaphragm, rigid” and “Diaphragm, flexible” were deleted from Chapter 2, and a sentence was added to 1604.4 stating when a diaphragm can be considered rigid, along with a reference to ASCE 7 for determining when designs must account for increased forces from torsion due to eccentricity in the lateral force resisting system.

In Chapter 19, significant improvements were made to the sections that modify ACI 318 so that the IBC and the standard are coordinated, correcting the problems in the 2012 IBC.  In addition, Sections 1908 (ASD design of anchorage to concrete) and 1909 (strength design of anchorage to concrete) were deleted to remove any conflict with ACI 318 anchor design methods.

In Chapter 23, a new section was added to address cross-laminated timber, requiring that they be manufactured and identified as required in APA PRG 320. The wood framing fastening schedule was completely reorganized to make it easier to use and the requirements for protection of wood from decay and termites were rewritten. Section 2308 on Conventional Light-Frame Construction was completely reorganized with significant revisions to the wall bracing section. As discussed in an earlier blog post, the holdown requirement for the portal frame with holdowns (now called PFH bracing method in the 2015 IBC) has been reduced from a required capacity of 4,200 pounds to 3,500 pounds.

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For designers, some of the most significant changes are in Chapter 35, which lists referenced standards. Some major standards that were updated for this edition of the IBC include ACI318-14, ACI530/530.1-13, several AISI standards (S100-12, S200-12, S214-12, and S220-11), several new and revised ASCE standards (8-14, 24-13, 29-14, 49-07, and 55-10), almost all the AWC standards (WFCM-2015, NDS-2015, STJR-2015, PWF-2015 and SDPWS-2015), AWS D1.4/D1.4M-2011, most NFPA standards (too many to list), PTI DC-10.5-12, SBCA FS 100-12 and TPI 1-14.

Kudos to the American Wood Council. They have posted view-only versions of all their referenced standards online, so designers do not have to buy new editions every time the code changes. AISI also enables one to download PDFs of the framing standards at www.aisistandards.org.

Finally, a couple of ICC Standards were updated to new versions that are referenced in the IBC: ICC-500-14, ICC/NSSA Standard on the Design and Construction of Storm Shelters; and ICC 600-14, Standard for Residential Construction in High-Wind Regions.

A future blog post will cover significant changes in the 2015 IRC. Please share your comments below.

Changes to 2012 IBC for Wind Design

The Greek philosopher Heraclitusis credited with saying “The only thing that is constant is change.”

If that applies to building codes, then it applies doubly to wind design using the 2012 International Building Code® (IBC).

The wind load requirements in Section 1609 of the IBC are based on ASCE 7 and refer to this document for most design information. In the 2012 IBC, the referenced version of ASCE 7 changed from the 2005 edition to the 2010 edition. In ASCE 7-10, the wind design requirements have been completely revised, including a complete design philosophy change.

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Wind design has changed from an allowable strength-based philosophy with a load factor of 1 in the ASD load combination to an ultimate strength design philosophy with a load factor of 1 in the strength design load combination. This means wind design has a similar basis as seismic design. So the new load combinations for wind look like this:

Strength Design: 0.9D + 1.0W
Allowable Stress Design: 0.6D + 0.6W

Because of the change in load factor and philosophy, the basic wind speed map had to be altered. In the past, one map was provided and the design return period was increased for certain occupancies by multiplying the load by an importance factor. In ASCE 7-10 there are three maps provided so now an importance factor is no longer needed. The return period of the map depends on the risk to human life, health and welfare that would result from the failure of that type of building. This was previously called the Occupancy Category, but it is now called the Risk Category.

Risk Category III and IV buildings use a basic wind speed map based on a 1,700-year return period. Risk Category II buildings use a basic wind speed map based on a 700-year return period. And Risk Category I buildings use a basic wind speed map based on a 300-year return period. Because of the higher return period, the mapped design wind speed will be much higher than when using previous maps. However, with the lower load factors, actual design loads will be the same or in many areas lower due to other changes in the way the map was developed.

wind map

Excerpted from the 2015 International Residential Code; Copyright 2014. Washington D.C.: International Code Council. Reproduced with permission. All rights reserved. www.iccsafe.org

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Another change to ASCE 7-10 for wind design is that Exposure D is no longer excluded from hurricane prone regions; so buildings exposed to large bodies of water in hurricane prone regions will have to be designed for Exposure D.

Because of the change in wind speeds, there is a change in the definitions of windborne debris regions. Due to the different wind speed design maps, the windborne debris region will be different depending on the Risk Category of the building being built. The windborne debris region is now defined as areas within hurricane-prone regions that are either within 1 mile of the coastal mean high water line where the ultimate design wind speed is 130 mph or greater; or any areas where the ultimate design wind speed is 140 mph or greater; or Hawaii. Risk Category II buildings and structures and Risk Category III buildings and structures (except health care facilities), use the 700-year Risk Category II map to define wind speeds for the purpose of determining windborne debris regions. Risk Category IV buildings and structures and Risk Category III health care facilities use the 1700-year return Category III/IV wind speed map to define wind speeds for the purpose of determining windborne debris regions.

Finally, a new simplified method for determining wind loading on ENCLOSED SIMPLE DIAPHRAGM BUILDINGS WITH h ≤ 160 ft has been added to ASCE 7-10. This is different from the simplified all heights method in the IBC, so it will be interesting to see which method becomes more widely used. Which method do you prefer? Let us know in the comments below.

How to Specify a Custom Hanger

As an engineer, it makes things easy when the buildings being designed are rectangular. This tends to make the connections occur between nice perpendicular members, and standard connectors and joist hangers can be used.

But buildings are not always rectangular and connections are not always between perpendicular members. Non-perpendicular members can have a skewed connection, where the supported member is moved side to side from perpendicular; or a sloped connection, where the supported member slopes up or down from a standard horizontal orientation; or a combination of the two.

To help with these situations, Simpson Strong-Tie offers a couple of options. The option chosen may depend on the timeframe in which the hanger is needed, the load demands on the hanger or the cost of the hanger.

If the demand load is low and an immediate solution is desired, Simpson Strong-Tie offers several adjustable hangers that can be skewed, sloped or both in the field.

LSU adjustable joist hanger

LSU adjustable joist hanger

A common adjustable joist hanger is the LSU/LSSU series, which can be sloped up or down and skewed right or left up to 45 degrees.

Remember that these hangers must be installed to the carried member prior to installation of the supported joist.

Other series of hangers are only adjustable for skew or slope.  For example, the THASR/L series is designed to accommodate connections skewed from 22½ to 75 degrees. Conversely, the new LRU ridge hanger is designed to support rafters at ridge beams with roof slopes of 0:12 to 14:12. Finally, the SUR/SUL/HSUR/HSUL series is not adjustable, but is manufactured with a skew of 45 degrees either right or left in several sizes.

THASL hanger

THASL hanger

LRU ridge connector

LRU ridge connector

HSUR hanger

HSUR hanger

If none of these pre-manufactured solutions fits your specific need, there are still options. This entails a custom-manufactured hanger. Many, but not all, joist hangers can be custom-made for specific slopes, skews, combinations of slopes and skews, and even alternate widths and alternate top flange configurations.

If this type of hanger is needed, a good place to start is the Hanger Options Matrix at the back of the Simpson Strong-Tie® Wood Construction Connectors Catalog. It is also available at strongtie.com.  An excerpt is shown below. This chart identifies which hangers can be modified, how they can be modified and to what extent they can be modified. There are two tables – one for top flange hangers and one for face mount hangers.

The Hanger Options Matrix is available in Simpson Strong-Tie(R) Wood Construction Connectors Catalog or at strongtie.com

The Hanger Options Matrix is available in Simpson Strong-Tie(R) Wood Construction Connectors Catalog or at strongtie.com

Once the user has found a hanger that can be modified to fit the actual situation, the next step is to calculate any load reductions, if applicable. The column at the far right gives the Wood Construction Connectors Catalog page number that lists any load reductions for the various options. If multiple options with reductions are specified, only the most restrictive load reduction needs to be applied, not all the reductions.

As an example, let’s say we need to hang a heavily loaded double LVL hip member from the end of an LVL ridge beam. We would look at a GLTV top flange hanger, skewed 45 degrees to the right, sloped down 45 degrees, with its top flange offset to the left. We see from the table above that all these options are permitted. If we go to page 220 (or strongtie.com), we can see what the load reductions would be for these options. The reductions are as follows:

  1. Sloped and skewed configuration for the GLTV has a maximum down load of 5,500 pounds.
  2. Offset top flange for the GLTV requires a reduction factor of 0.50 of the table roof load.
  3. BUT, skewed and offset top flange hangers have a maximum allowable load of 3,500 pounds.
  4. Offset top flange results in zero uplift load.

So the allowable load of our skewed, sloped, offset top flange GLTV would be 3,500 pounds downward and 0 pounds uplift. In this case, it was clear what the reduction was for our combination of modifications. If it is not listed specifically and you have multiple modifications with multiple reduction factors, use only the factor that results in the biggest reduction, not all of the listed reduction factors.

The next thing to do is to call out the desired hanger properly so that Simpson Strong-Tie can manufacture it to your needs. This is typically done by taking the regular product name, adding an X, and then calling out the modifications individually at the end.

For our hanger, assuming the hip is 3-1/2″ by 11-7/8″, the standard hanger would be a GLTV3.511, and the modified hanger would be called out as a GLTV3.511X, Skew R 45, Slope D 45, TF offset L.

There is one final consideration when hangers are both sloped and skewed. In this case, the top of the supported member (joist) will not be horizontal when it is cut, one side will be higher than the other. The user must decide and specify where he or she wants the upper side of the joist to fall. There are three options: high-side flush, center flush or low-side flush. We see that often users will want to specify high-side flush so that the joist ends up flush with the top of the supporting member, but that would be up to the user. This specification is added to the end of the callout name listed above. These cases are illustrated below.

A related matter occurs when the top flange of a hanger is sloped up or down. In this case the user also has to specify whether the joist is to be low-side flush, center flush, or high-side flush. But, in this case, the side is in reference to the top flange, not the joist. Specifying low-side flush will result in the top of the joist being flush with the lower side of the sloped top flange, not the low side of the joist.

If all of this seems confusing and somewhat difficult, it can be. Fortunately, Simpson Strong-Tie has developed a new web application – the Joist Hanger Selector – which automates this entire process. This app is located on strongtie.com/software.

Once you agree to the terms and conditions, choose the type of hanger you want to specify, then select the types of members being connected. This is what it would look like for our example.

jhs-input

 

This is where the user specifies any modifications required. Required loads can also be entered at this point. This is what it would look like for our example.

jhs-input2

Then, just click “CALCULATE” and the possible options will be shown. And here we see our GLTV3.511X, SK R 45, SL DN 45, TF Offset L, with a load of 3,500 pounds, just as we thought! I love it when a plan comes together.

jhs-input3

Hopefully, this web app will help you specify custom hangers with ease. Are there any other applications we could develop that would make specifying connectors easier? Let us know.

Upcoming events

The 22nd International Specialty Conference on Cold-Formed Steel Structures is coming up Nov. 5-6 at the Hilton Ballpark Hotel in St. Louis, MO. It is sponsored by the Wei-Wen Yu Center for Cold-Formed Steel Structures at the Missouri University of Science and Technology.

A biannual event, this conference brings together leading scientists, researchers, educators and engineers in the field of research and design of cold-formed steel structures to discuss recent research findings and design considerations. This year’s conference features 12 technical sessions covering a wide variety of topics. For more details, visit the conference website.

New Holdown Requirements for the IRC® and IBC® Portal Frame Bracing Method

The IRC® contains several different narrow bracing methods that are made up of portal frames. One method that is useful if you are using intermittent wall bracing is the Method PFH Portal Frame with Holdowns. This method relies on low-deflection holdown anchorage at the bottom, and substantial nailing at the overlap of the sheathing and the header at the top to prevent overturning of the narrow panel. An identical method for use as wall bracing is in the Conventional Construction section in Chapter 23 of the IBC®. These portal frames were first included in the 2006 IBC and IRC.

Method PFH- Portal Fram With Holdowns

Method PFH- Portal Fram With Holdowns

The method was originally tested with straps clamped to a steel test bed to simulate the embedded holdown straps. The straps were nailed to the wood with enough nails to mimic a 4,200 lb. strap anchor. The original test report is APA T2002-70. At that time, the Simpson Strong-Tie® STHD14 had a published allowable load in excess of 4,200 lbs. based on then-current Acceptance Criteria, so hardware was available to construct this frame throughout the country. However, in 2008, ICC Evaluation Service developed a new acceptance criteria for embedded connectors, AC398, Acceptance Criteria for Cast-in-place Cold-formed Steel Connectors in Concrete for Light-frame Construction. This was in response to the changes in ACI 318 for anchors in concrete. When re-tested and evaluated using the new Acceptance Criteria, the allowable load for STHD14 was reduced below 4,200 lbs. for use in buildings designed for Seismic Design Categories C through F.   The same thing happened to other manufacturers’ embedded holdown allowable loads. That made it impossible to properly construct this bracing method in those areas. In response to this, Simpson Strong-Tie worked with APA, the Engineered Wood Association, to design a new test that would determine if a lower capacity holdown could be used with this portal frame method.  APA performed the testing at their Tacoma, Washington testing lab. Since the initial testing of the portal frames with the 4,200 lb. holdown was performed using the outdated SEAOSC protocol with an older testing rig that used a stiff beam above the wall, both the old tests with a simulated 4,200 lb. holdown and new tests with a simulated 3,500 lb. holdown were rerun in accordance with the current ASTM E2126 test method using the CUREe protocol. The test was published as Test Report T2012L-24. The tests showed little to no effect of reducing the holdown from 4,200 lbs. to 3,500 lbs. allowable load. Here is one of the graphs of the backbone curves comparing the two assemblies for a 16-inch wide, 10-foot tall portal frame.

Comparison graph of two assemblies for a 16-inch wide, 10-foot tall portal frame.

Comparison graph of two assemblies for a 16-inch wide, 10-foot tall portal frame.

With the testing complete, APA prepared and submitted code changes to both the 2012 International Building Code® and 2012 International Residential Code®. The IBC proposal is S291-12, and can be found on page 605 of the 2012 Proposed Changes to the International Building Code – Structural. The IRC proposal is RB311-13, and can be found on page 613 of the 2013 Proposed Changes to the International Residential Code-Building. With support from Simpson Strong-Tie, both of the proposals were approved. So in the 2015 IRC, bracing method PFH will require an embedded strap-type holdown with a minimum capacity of 3,500 lbs. instead of 4,200 lbs. The same will hold true for the Alternate Braced Wall Panel Adjacent to a Door or Window Opening bracing method in the 2015 IBC. APA also re-tested the portal frames with only two sill plates instead of three. This will allow the use of a 5/8” by 8” Titen HD® anchor as a retrofit anchor bolt. What are your thoughts? Let us know in the comments below.

Wood Design Education Opportunities

Designing wood structures properly requires a broad knowledge base of a variety of materials and how they go together.  However, it can often be difficult to find educational opportunities for designers to learn about wood design or keep up with new technologies on wood construction.

Fortunately, there are some unique chances this summer to increase your knowledge about wood as a construction material.

There is a short course titled Advanced Design Topics in Wood Construction Engineering, being held May 21 and 22 at Virginia Tech University in Blacksburg, VA.  It is intended for designers, inspection professionals and builders that want to expand their general knowledge of wood as a building material and their knowledge of building design beyond the introductory level.  The agenda includes sessions on Decay Processes, Design for Durability, and Insects that Attack Wood; Wood Shrinkage Issues in Construction; Lumber Grading Methods and Design Values; Design of Built-Up Beams and Columns; Glulam Beam Design; Evaluating Structural Capacity of Fire-Exposed Timber Beams and Columns; Multiple-Bolt Wood Connection Design; Basics of Diaphragm and Shear Wall Design; Post-Frame Building Design and Diaphragm/ Shear Wall Tests; Creep of Solid-Sawn Joists, I-Joists, and Floor Trusses; Design Considerations for Preventing Flat Roof Failures from Gravity Loads or Sustained Live Loads; Wood Truss Design Responsibilities; Wood Truss Repair Design Techniques; Permanent Truss Bracing Design Basics; and Lateral Design of Decks.

You can find more information about the Virginia Tech Short Course here. Web registration ended May 14, 2014; you can register by calling the Conference Registrar  (540) 231–5182 up to the first day of the course.

If you feel like travelling, the World Conference on Timber Engineering (WCTE) will be held in Quebec City on August 10-14.  WCTE is an international biannual event focusing on timber engineering, engineered wood products and design of timber structures.   The conference theme is “Renaissance in Timber Construction.” Information on the conference can be found here.

But you don’t have to necessarily travel far to get quality training on wood design.

WoodWorks is a cooperative venture of major North American wood associations, research organizations and government agencies that aim to encourage and assist architects, engineers and others in the use of wood in non-residential and multi-family buildings.  WoodWorks deliver knowledge to designers in three main ways:  webinars, short 2-3 hour seminars and Wood Solutions Fairs.  Upcoming webinars include Mixed Use Podium Design, Changes to Wood Design Standards and Healthy Buildings.  Seminars scheduled for June focus on Cross Laminated Timber in California, Pennsylvania, Texas, and Washington.  Finally, Wood Solutions Fairs are excellent all-day events where attendees can choose from more than 15 classes in six sessions throughout the day.  The Fairs also include exhibits to allow for networking with building product manufacturers.  Upcoming Wood Solutions Fairs are May 22 in Chicago, August 27 in Washington, DC, October 23 in Portland, Oregon, and November 12 in Arlington, Texas.  Here is a full schedule of WoodWorks events.

If you just can’t get out of the office, or you don’t like to travel, there are still ways to keep up with the wood industry.  Several groups offer webinars or self-study classes on various subjects.

WoodWorks, mentioned above, is a good resource. The American Wood Council (AWC) is the voice of North American traditional and engineered wood products, representing more than 75% of the industry.  AWC’s engineers, technologists, scientists, and building code experts develop state-of-the-art engineering data, technology, and standards on structural wood products for use by design professionals, building officials, and wood products manufacturers to assure the safe and efficient design and use of wood structural components. AWC also provides technical, legal, and economic information about wood design, green building and manufacturing environmental regulations advocating for balanced government policies that sustain the wood products industry.  AWC has begun offering regular webinars on various subjects with complimentary registration.  Upcoming webinars include the AWC Prescriptive Residential Wood Deck Construction Guide on May 22, AWC Web-based Calculators and Other Resources on June 24, and Prescriptive and Engineering Design per the 2012 WFCM will be offered some time in the fall.  Also, AWC has a comprehensive library of e-courses on their website as well as a helpdesk via email, info@awc.org.

In addition, the International Code Council offers a variety of online training classes as part of their ICC Campus Online.  Most have a nominal fee, but several are available free of charge.  They have a Catalog of Classes on their website.

And finally, don’t forget about resources available from Simpson Strong-Tie. These resources range from full and half-day workshops offered at various locations throughout the country to online courses you can take from the comfort of your own office.  Many of these courses come with CEU credits and some also offer AIA credits.  And if you would like a personal visit, such as a lunch-and-learn, contact your local sales rep, or one of our regional offices and ask to speak with the training manager.

Do you know of any other good events coming up?  Keep the conversation going.