Contributed by Liz O'Sullivan
Recently, I was preparing a masonry architectural specification section for a remodel project. The project has an existing CMU wall which is to receive a small area of new CMU infill. It’s an exterior structural wall, and the architectural drawings indicate that the infill CMU is to be grouted solid.
I asked the structural engineer if we need reinforcing bars (rebar) in the cores of the CMU. I told him that I would delete rebar from the spec section if we don’t need rebar, so that the Contractor knows he doesn’t need to provide it.
The engineer said, “You can just leave it in the specs. If the rebar isn’t on the Drawings, they’ll know they don’t need it.”
Drawings and Specifications are complementary and what is called for by one shall be as binding as if called for by both.”
This is according to the General Conditions of the Contract for this project. This is a typical provision in construction contracts. (1)
So, if rebar isn’t required for that wall, there should be no rebar in the spec or on the drawings. If rebar is in the specs, even if it’s not on the drawings, rebar is required by the contract. If rebar is on the drawings, even if it’s not in the specs, rebar is required by the contract.
Design professionals need to completely comprehend this concept, and for some unknown reason, many don’t. Contractors need to completely comprehend this requirement, and for an understandable reason (it’s not in their best interest at times) they don’t always seem to grasp this.
The lead design professional on the project, the entity who is performing construction contract administration, is the party who must enforce the contract documents, including the specifications. This party has to understand the relationships among contract documents before he or she can properly enforce them. If the specifications and drawings have been prepared to be complementary, and are clear, concise, correct, and complete, they will be easy to understand (for all parties) and easy to enforce.
Contributed by Chris Maskell
The flooring industry is constantly challenged by the same repeating issues. Installing too early, wet concrete, non-flat sub-floors, sub-floor surface not prepared, heat not on, windows not in and lack of installer training and certification. In fact, as construction speeds up to meet demands for faster build times and with the threat of an increase in the cost of borrowing money lurking in the economic wings, the provision of acceptable conditions for the flooring contractor is becoming less likely.
This raises the importance of supporting those in the construction team (Building Owner, Construction Manager, General Contractor, Design Authority, and Flooring Contractor) with good, timely information that helps all involved plan ahead for the floor covering installation. As one of the last significant trades onsite, the flooring contractor needs certain conditions, that if not planned for in advance, will be next to impossible for the Construction Manager/General Contractor to provide without extra time and/or extra money: two things in short supply at the end of a build or renovation.
Change is possible, but requires a few things to be understood and acted on in advance.
There is a generic Canadian floor covering industry reference manual available for specification, which supports all construction parties, and when included in the Division 09 section of the construction documents, means correct flooring processes and supportive language is available to guide the floor installation and all the points listed below.
Contributed by Laverne Dalgleish and Roy Schauffele
In the last few years, a lot of attention has been placed on the proper installation of continuous insulation in buildings (editor: As per EnergyCodes.gov, continuous insulation is defined as insulation that runs continuously over structural members and is free of significant thermal bridging; such as rigid foam insulation above the ceiling deck. It is installed on the interior, exterior, or is integral to any opaque surface of the building envelope). The purported reason for this has been to stop the thermal bridging that occurs when you put thermal insulation between steel studs.
Years ago, we started out insulating our buildings by requiring a certain R-Value insulation to be installed in the cavities. In those days, wood framing was very common. As we moved to steel studs in commercial buildings, we realized that the building assembly was performing less than the R-Value of the insulation. From that, we started requiring an “effective thermal insulating value”.
Today some building codes simply require a maximum U-Value for the building envelope, which is supposed to reflect the thermal performance of the building assembly. But does it? In most cases, the answer is “not really”.
When we look at the requirements in the International Building Code and in ASHRAE 90.1, the basic principal of overall building assembly U-Value is there, but the only requirement is that you take into consideration the primary framing members (in a lot of cases, simply the studs). This is a good first step.
If we want to get to truly energy efficient buildings, we need to look at all thermal bridging materials that are incorporated into the building assembly. Not only should the main structural beams be calculated and the steel studs, but we need to look at all thermal bridges. This includes Z channels, fasteners, brick ledges, hat channels, masonry ties, balconies, parapets and anything else that will transfer heat. But the codes are not yet there.
Peering in to the future, there are some manufacturers that are starting to develop thermal break materials, and designers are starting to incorporate thermal breaks into their building envelope design. This is a desire by forward-thinking architects.
Today, the International Building Code and ASHRAE 90.1 do not require you to take all of the thermal breaks into consideration and you do not have to include them in your modeling. The Z channel is a common method used to be able to structurally support the cladding system. Is it a thermal break? Yes. For code purposes, do you need to consider it? No. That is a disconnect between code requirements and good building practice.
We want to reduce the energy use by our buildings and the building envelope provides the biggest opportunity. We need to bridge the thermal gap between what is required by the codes and what is good building practice. Having requirements for continuous insulation was a good step forward. We need to keep going.
This article was originally published by the Air Barrier Association of America under the title 'How Continuous is Continuous? And what about Z channels?' and a PDF may be downloaded here.
Contributed by David Bishton
Breakfast? With a specifier? You may wonder about the wisdom of such an engagement, but it is a unique experience. It occurred to me today that there are some uncanny similarities between project specification preparation and the simple (or complex) task of preparing breakfast. In this case, breakfast for a crowd.
The first thing to know is that the Specifier comes to YOUR house, either in person or virtually or both, to help YOU plan and make the breakfast. So wait, I can hear you say, the SPECIFIER DOES NOT DO ALL THE WORK? In case you hadn’t noticed I use capital letters for emphasis – I learned it from this really smart 5th grade (I assume) kid I found on Twitter. Anyway, the answer is no, but the Specifier can be your most able assistant.
So how does it work? The first thing I as a Specifier want to know is more about what’s on the menu – what did you have in mind to serve this big crowd that you’ve invited over? Oh, it’s a pot luck! You have the main course and everyone is bringing something to the table. So how can I help – what’s in the fridge?
I open the refrigerator door and what to my wondering eyes should appear? A miniature sleigh – wait, that’s from another story – a really large tray of the most beautiful eggs I’ve ever seen. And every nook and cranny stuffed with marked and unmarked containers of every size and shape. You are REALLY PROUD of those eggs! So how can I help? I can chop onions, garlic, veggies, make sausage, prepare a fruit salad, get all the herbs lined up, make toast, help set the table – I’ll even go to the store if you need something. Just tell me what you need. “First, look through this 150 page recipe and find the ingredients. Then figure out what’s in all these containers. I might be missing some things.”
Contributed by Roy Schauffele
The air barrier technology used in today’s construction and mandated by the International Energy Conservation Code (IECC) are firmly grounded in science. That database of knowledge continues to grow at an astounding rate. Research efforts by the Air Barrier Association of America (ABAA) will be presented at the ABAA Conference in 2019, and you will be astounded by how much research and testing that ABAA has been conducting to ensure better knowledge for all.
Currently, air barrier systems are being marketed with having passed only the air barrier part of the testing (ASTM E2357 - Standard Test Method for Determining Air Leakage of Air Barrier Assemblies) and pay little to no attention to the other architectural performance attributes, such as crack bridging, water resistance, adhesion to a substrate and fastener sealability, which when successfully passed, results in an ABAA Evaluated Assembly.
So, what I’m asking you to consider is an upgrade of performance requirements for a better and stronger air barrier specification. Here are my suggestions for ensuring the best possible air barrier performance for your project:
Performance requirements for a proper air barrier specification are vital. The above are four of my suggestions as how you can elevate and upgrade your specs. Should you have any questions or comments, I appreciate you commenting below. Thank you for reading.
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