Contributed by Michael C. Kerner Many factors must be considered when a design specifies cold-formed steel framing members. Material selection will impact nearly every member of the construction team including the architect, engineer, specifier, code official, distributor and contractor - and could even impact the safety of building occupants. Therefore, it is imperative that there’s an understanding of requirements needed for steel framing members to be designated as code compliant.
One of the most commonly specified materials for commercial construction is steel. Generally used for both load-bearing (structural) and non-load bearing wall and floor systems (non-structural), millions of pounds of the material is used every year for the non-combustible construction of office and apartment buildings, hotels and hospitals across country. But, how does a contractor know if the steel studs being purchased meet International Building Code (IBC) and ASTM requirements? For some products, such as fire-rated doors, this is easy because the products bear the label of a recognized third party inspection agency. For the architect, builder and general contractor, it is important that they receive the building products the specifications demand. For metal studs, ASTM C645 (drywall framing) and ASTM C955 (structural framing) are the standards referenced in the code. These documents specify the minimum criteria for: decimal thickness, type and weight of protective coating, mechanical properties of the steel, physical configuration of the stud and labeling requirements. Without meeting all the requirements, metal studs are not code compliant. For example, a structural load-bearing stud is required to list the “coating designator”, CP-60, in the ink jet stream and in all supporting literature. The same consideration should be given when writing the specification, the coating designator, CP-60, should be listed. All these criteria must be met for a steel stud to be code compliant. Building Occupant Safety In addition to the building code requirements, there is one other important issue that must be recognized by both the installer and the design professional. The use of non-compliant material can create life-safety issues. For example, if a stud is required to be a certain thickness to attain a specific limiting height and/or carry a certain load, what effect is there when a thinner metal is used than what is specified? The stud may fail and cause injury to the building occupants, or in a life-safety situation such as a fire, the rated partition may fail and it would not allow the building occupants time to escape. It is also possible that an individual product is code-compliant, yet it will not perform as intended in a life-safety situation. As an example, a metal stud could meet the minimum requirements of ASTM C645 yet not meet the requirements of the fire-rated assembly in which it is used. How is this possible? Word of Caution Keep in mind that ASTM specifications are minimum requirements for the product. These requirements must be checked against the actual products used in a tested assembly. For example, the disconnect can occur when comparing building code requirements against the method in which a given fire-rated assembly must be constructed. For example, if an architect’s partition schedule calls for UL Design U411, but only calls out the depth of the stud, then the following scenario may occur: The contractor will supply a stud that meets the project specifications, which call for the product to comply with ASTM C645. However, if the actual tested assembly were researched, it would reveal that the stud would require a return lip of 3/8 inch (10 mm). This is much larger than the 3/16-inch (5-mm) return lip C645 requires. Therefore, the partition would not meet the fire-rated assembly construction requirements. The correct products and proper assembly must be employed or life-safety issues are raised in the building. If the proper products cannot be sourced, then a different tested assembly may need to be substituted. Knowledge of the building codes for your jurisdiction is imperative to determine if a product is code-compliant. If you are not sure, ask your manufacturer. It may take some extra time to research, but when the integrity of the products and our industry are at stake, it would certainly seem worthy of our attention.
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Contributed by Neil O’Connor Today I read a great blog titled “Let’s Fix Construction” authored by Cherise Lakeside. The Blog dealt with some of the excuses and sometimes valid reasons we encounter issues on projects and introduced an organization named “Let's Fix Construction. Their Website is LetsFixConstruction.com and I would encourage you to read it. This Let's Fix Construction blog shows that other sectors of our industry, specifically the design sector, are also embracing the need to adapt to a new and improved model. This is something that from a Contractor’s point of view I am excited to hear.
In the blog, Ms. Lakeside has opened what some might consider a Pandora’s Box. However, those with the ability to look at the big picture will see a path to a brighter future. Many of the phrases she opened her blog with are the result of the teaching methods of the Greatest Generation to the Baby Boomers. Boomers often when given a new task were basically put into sink or swim situations, thus it was easier and safer once you learned how to do something to not vary from it. We were often told “you are not getting paid to think.” Mentoring was a rare, if not nonexistent, concept for Boomers to learn by. Today there is a brighter future for our industry, as some Boomers have had the foresight to break out of that mold and realize there are different and often better ways to accomplish a common goal and that with some training and mentoring the new generation coming up can have a higher success rate when given new tasks and roles. Those with the foresight are teaching that improved communication and out of the box thinking can often lead to Win-Win solutions. The upcoming Millennial Generation has an opportunity to totally refashion the Construction Industry for the better with their innate desire to be part of a team. Many of our current issues with designing and building a project are often the result of one or more individuals or companies with a “my way is the only way” attitude. Please note this is a Boomer that is excited about the potential of the Millennials. One of the primary concepts Ms. Lakeside promotes is learning about other facets of this industry. Expanding our understanding of how the work and thoughts of others may interact with the issues of our particular part of a project. Since time and resource limitations affect our ability to individually understand, all such possible interactions forming teams with a broad variety of experiences would appear to offer a viable opportunity to expand everyone’s view while reducing the anxiety of everyone trying to protect their “turf”. Within the context of such teamwork below are a few concepts, which if implemented, could radically change our industry: 1. More time to work together will result in less cost. It is said “time is money”. In our industry it is the lack of time that will always cost everyone more money. When a Design Team and a Construction Team (including Subcontractors) are given time to work together, especially with the advent of BIM modeling, the results tend to be far different and better than some projects of old. Fewer clashes, problems, arguments, workflow stoppages, and claims which will result in more savings for everyone including the owners. Contributed by Sheldon Wolfe Among the things specifiers grumble most about are the typical architect's lack of knowledge about how things work and how they go together, and the belief that "If I can draw it someone can build it!"
Some architecture schools do include courses about the practical aspects of architecture, but those courses are often optional, so most architects graduate with a lot of knowledge about visual design, planning, and presentation, but little understanding of materials or construction. It's fine to have a presentation about masonry, but so much more could be learned from participants getting their hands dirty. It's easy to draw a 4 x 4 x 8 brick, but what does it feel like? It takes no more effort to draw a 3-5/8 x 2-1/4 x 11-5/8 brick or a 3-5/8 x 3-5/8 x 15-5/8 brick, or, for that matter, a 12 x 8 x 16 concrete masonry unit, but what difference does it make to the mason? It doesn't take any longer to draw a large masonry unit, but does the size affect installation time? Until you pick up a brick, mix the mortar, and try to build a wall, you simply cannot appreciate what your details mean in the real world. This shortcoming presents a tremendous opportunity for continuing education programs. In June of 2000, twenty-five architects from my office went to the masonry apprentice school in St. Paul for an afternoon of fun, down-and-dirty continuing education. The program was set up by Olene Bigelow, our local International Masonry Institute (IMI) rep, and contact for the Brick Industry Association (BIA). The apprentices set up a series of stations, each showing a specific part of the job. Demonstrations included reading drawings and specifications, estimating, mixing mortar, laying brick and CMU of various sizes, installing door frames, and more. After the book learnin' discussions, the architects got their hands dirty at each station and learned how their decisions affected construction and schedule. The Minneapolis-St. Paul Chapter of CSI visited the school and followed the same program. It's easy to complain about what architects don't know, but they are not alone. Specifiers may know more of the technical properties of materials, but many have had no more practical experience in construction than architects. I used masonry as an example, but similar programs could be done for everything that goes into a building. ALL of us can us do better if we know more about how other team members do their jobs. Contributed by Eric D. Lussier I’m quickly approaching eleven years working in and around indoor flooring, focusing mainly on sport and synthetic surfaces. Eleven years of projects of all shapes and sizes ranging from 250 square foot residential basements to 30,000 square foot college field houses. Eleven years of existing conditions, renovations, rehabilitations and new construction and the one constant that rears its ugly head on almost each job are substrate conditions, and especially concrete moisture. Conversely, said moisture issues are seemingly new news to whomever I am working with: whether that is architects, construction managers, general contractors or end users.
There are more than a few instances that can lead to high moisture in a concrete slab. Whether it is an over-watered pour, a lack of a quality vapor barrier, a compromised vapor barrier, or a missing one entirely (either from degradation or lack of placement), a fast track installation with insufficient time for the concrete to dry, an inoperable or missing HVAC system or a handful of other events. No matter the occurrence, it can all equate to the same headaches after the fact. Normally fingers are pointed, voices are raised, materials are ripped out and unnecessary time and money is spent to potentially repair or replace flooring that perhaps should have never been installed to begin with. Industry-speak may call it “flooring failure” but most of the time the flooring is performing exactly as it is supposed to. The adhesive on the other hand, may be completely failing. New construction technologies have our buildings tighter than ever. With the use of a proper vapor barrier removing the ground from the equation, concrete moisture has no place to go but up and through the slab. When placing a fully adhered, non-breathing floor, such as a heat-welded sheet vinyl on the slab, concrete moisture in an untreated slab travels up and out, trying to push through the adhesive and new floor in the process. Even though the norm in the industry has raised from 3 lbs. of moisture to 5 lbs., as per ASTM F1869-11 (Standard Test Method for Measuring Moisture Vapor Emission Rate of Concrete Subfloor Using Anhydrous Calcium Chloride), that limit can take substantial time to achieve when it comes to new construction. Speaking of norms in the industry, thankfully most flooring manufacturers have moved away from recognizing calcium chloride testing (which is more of a snapshot of what is happening emanating from just the top of the slab) towards in-slab relative humidity (RH) testing (what is going on inside the slab). Testing as per ASTM F2170-11 (Standard Test Method for Determining Relative Humidity in Concrete Floor Slabs Using In-Situ Probes (has become easier over the last handful of years with developed equipment, including testing probes that can be left in the slab and reusable digital probes. It is always recommended that an independent third-party is specified to test the concrete for moisture and not the General Contractor or flooring contractor themselves. It could be viewed that each party has a vested interest in ensuring that results are swayed their way. If you are looking for a certified concrete moisture testing party, the International Concrete Repair Institute offers a moisture testing certification program and you can search the certified testers here. Contributed by Margaret Fisher Submitted Title 'Waaaaay Too Much Information!' Time is Neither Unlimited Nor Elastic
As the company I work for gets invited to bid on projects around the country by over 560 GC’s, I see a lot of these. As you might imagine, these forms ask a lot of the same questions. In today’s world of “every second counts” and lean measures, I am all about eliminating redundancies. So about 5 years ago, I started collecting the questions being asked on these forms and compiled ONE big “Standard Pre-Qual Info” document. Today, there are about 200 questions on it. I keep that updated quarterly and when we get a request to complete yet another pre-qual form, I send this instead and tell them our president will make an appointment with their financial person to review OUR financial info in a closed door, one-on-one meeting. We do not leave the financials behind. We are not alone in this practice. In 99% of those cases, they never bother to set up this appointment. And 99% of the GC’s I send this to say I’m not alone and that works just fine. It’s the ones that insist on online completion because of some kind of (meaningless) score that gets computed that insist on this. The info is not better it just eats up a ton of time. Time one could use doing some actual work that would be beneficial to the quality completion of a project. What happens if we don’t fill them in? We get the job anyways. Testing This Out So let’s build this common scenario. Say a typical project is going to require the work of 15 trades. 1 x 15 = 15. Each CSI Section is bid by a minimum of 3 subcontractors, but could be bid by 8-10 or more. So, let’s say 5 for each trade. 5 x 15 = 60. Each prequal form is 10 pages minimum. 60 x 10 = 600 pages of pre-qual info to review. Whew! That’s a lot to analyze. So I asked a great CSI, AIA brilliant friend of mine to lunch one day to discuss this phenomenon. He does get involved in the subcontractor selection process and is very keen to have high quality skilled individuals on his projects. I asked him how he has time to read 600 pages of all this info that 60 subcontractors submitted. He says he gets the info but doesn’t read them. I asked, “How much of this info is used to make the selection of the subcontractor?” He said, “None of it.” I needed a moment to let that sink in. This is staggering because we’re talking about 60 companies wasting 10 hours apiece on something that isn’t used. (And people wonder why productivity is so low. Probably partly because of the lure of social media, etc. but, also because of irrelevant activities like this.) So I asked, If the GC is insisting on this and if it isn’t used, what DO you use to make the decision instead? He said, he does what everyone else does; look at the prices, remove the proposals that are not realistic, see who’s including the most scope, think about who they used recently, thought about how the project went and chose the one they liked working with.” All these business questions don’t help him decide who works on his projects. So Who Cares? After a delightful lunch, I dropped him back at his office and we went our separate ways but, I had to ponder the remaining question. What is actually NEEDED to determine which subcontractor is right for the job? You would have to have qualification questions about the tradesmen skill itself on the questionnaire. This has not happened. I then went to the office of the Executive Vice-President of a large trade organization that is baffled by this whole thing as well. After about 2 hours of discussion we came to this: Get a room full of the estimators of all the GC’s in the area in one room and give them a single sheet of paper and a pencil. Tell them they have to determine which of 5 Subcontractors in one trade will be given a contract for that trade. They can only ask ONE question. What would the ONE question be? What is the info that assures them the subcontractor has the skills to do the job as specified? I think if you took the top 5 answers they come up with, you’d have the makings of a new pre-qual form that works. |
AboutLet's Fix Construction is an avenue to offer creative solutions, separate myths from facts and erase misconceptions about the architecture, engineering and construction (AEC) industry. Check out Cherise's latest podcast
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