In a FEA-driven design that owes more to aerospace engineering than carpentry, SigmaDek Ltd. recently developed a residential deck system that replaces lumber with an all-aluminum substructure consisting of die-cast and extruded components. The new deck system, the first of its kind, is the latest piece of evidence that die casting continues to push into new and unconventional applications.
SigmaDek’s patent-pending deck system makes use of extrusions for the ledger board, beams, joists, and railings. Thirty-one die-cast components, produced by Dynacast, serve as the connectors that hold the extrusions together, creating a unified structure. The system is “deck board neutral,” meaning that the contractor can use any common wood, plastic, or composite decking material.
While aluminum is not a traditional structural material for decks, it turned out to be a smart choice for this application because it allowed SigmaDek’s engineering team to create a structure that is maintenance free, easy to install, and consistent in its structural performance. As SigmaDek president Gary Acinapura points out, deck cost and safety are heavily dependent on the skill level of the contractor with site-built carpentry decks. Some contractors can build a safe, strong deck for a reasonable cost. Some cannot, as shown by the deck failures that periodically make the local news.
SigmaDek, by contrast, does not depend on the skill of the contractor. Thanks to the design freedom available from manufactured aluminum components, the deck system has a wide range of user-friendly, fool-proof assembly features. These include integrated bubble and laser levels to align the substructure. The aluminum components also incorporate numerous locking features that allow components to be joined only one way -- the correct way.
For all its advantages in this application, the all-aluminum substructure posed some difficult engineering challenges related to the strength and manufacturability of SigmaDek’s die-cast components.
Strength was a challenge that had to be addressed early in the design process -- though not because there was any doubt that aluminum components could carry the necessary loads. SigmaDek’s VP of engineering, Brian Boettger, explains that the SigmaDek system represents an entirely new use for aluminum components, so the International Building Code had no provisions for this type of structure. As a result, the deck had to be engineered with a safety factor that’s roughly 2.5 times greater than the building code would specify for a wooden deck structure, driving up design stresses substantially. To take one example, the connector between joist and stair stringer has to withstand localized stresses in excess of 15,000 psi, far above what it’s likely to see in use.
Stresses of that magnitude fall well within the capabilities of die-cast aluminum. Yet SigmaDek engineers wanted to make sure strength didn’t come at the expense of economical casting or feature integration. Thicker wall sections or ribs, for example, might make it easier to meet structural requirements, but they can also add cost to the casting process. So SigmaDek's engineers decided to favor thin-wall structures whenever feasible, adding box-like structures and ribs where needed. Many of SigmaDek's parts have localized wall thicknesses down to 1mm, about half what a less carefully designed part would have required to meet the load requirements.
Walls this thin are not necessarily a problem for Dynacast die casting processes, which can handle wall sections down to 0.5 mm. But the thin-wall parts did require extra optimization from both structural and design-for-manufacturability (DFM) standpoints. For the optimization, SigmaDek collaborated with a product design firm, Precicad Ltd., which performed extensive FEA work on individual components and the structure as a whole. For the DFM work, SigmaDek turned to Dynacast engineers, who suggested dozens of design modifications to improve the manufacturability of the deck system's thin-wall, complex parts. These changes ranged from the elimination of undercuts and the addition of draft angles to the refinement of gates, runners, and overflow design.
Most homeowners nowadays have been improving their house so that they would look more attractive that would catch people's atention whenever they will be walking around your place. This can be achieve if you will be looking for a trusted company that would be offering you this kind of service. With the help of home remodeling Morgan Hill services you will be ensured that you will be receiving a great service from them. This is a wonderful thing for you can be able to transform your area according to your original plan that would make you feel more contented and happy.
These days, more and more home owners try to maxmize their living spaces by having haveing home addition projects outdoors like that of patios, gazebos or decks. This idea not only adds beauty to the overall appearance of the house but it alsoadd functionality as members of the family get to spend time outside. There are San Antonio patio builders as well as in other state who create customized concepts for various house styles and this is great since no two houses are identical. Matching the lifestyle of the home owner, a dye-cast decks will be added to the residential construction trend anytime soon.
Depending on your lifestyle, it may be difficult for you to maintain the even appearance or quality of your flooring especially if you have outdoor additions like a deck patio since it is exposed to various weather conditions. This is why it is important to learn basic information such as the ones given above because others might that they are mundane but there will come a time that they will come in handy. With the assistance of home improvement blogs, reliable home builders Missouri contractors and other sources of information, we get to know more about how to care and maintain not just our flooring but the entire household as well.
David, while I can't really offer any suggestions relative to what type of decking you could install to reduce the heat situation, I can tell you that aluminum is a fairly poor conductor of heat and therefore would NOT contribute to the overall temperature on your deck. I have taken a section of our aluminum joist and placed it in the sun for several hours during the heat of the day and was able to pick it up with my bare hands.
I suspect the only thing you might be able to do to mitigate the suns effect would be to create some sort of shade either with a pergola, gazebo or awning. Even very light colors get hot under direct exposure to the sun.
I haven't seen anything in here about the temperature of the decking. Here in Alabama where we have had too many days this summer with temps of 99° F and heat indices of 110° F, how hot would an aluminun deck be? I walked out on to my wood deck to water the flower boxes and jumped back indoors after only a few steps to look for my sandals. I'd really like to find something that would replace the deck planking, as mine is starting to splinter from age and wear. I am to the point I am about to consider replacing the decking.
For those whom I know will be kind enough to offer suggestions, my deck is all wood (so far,) 16' X 20', and on the east side of the house, where the shade starts at 2:30 in the afternoon and covers the deck by 5:30 or 6:00.
There are so many materials that can be used for decks and other outdoor spaces. Choosing the suitable one needs a bit of information to help you choose well. http://www.bclumberstore.com is source of quality materials anddesign tips for your decks.
Brian, thanks for responding. How about lifetime costs? It says on your website that the upfront costs may be 25 - 35% higher than a comparable wooden deck. It would be interesting to know how long it takes that initial expenditure to pay for itself. I'd imagine it wouldn't be hard to calculate with some estimates of maintenance cost and the difference in expected lifetime.
Also, what about sustainability? Your website says "safe, strong, sustainable" but it would be interesting to know how it stacks up against wood in that regard. Wood is a renewable material; aluminum is a recyclable material; it would be good to know how they compare. There has been some discussion on this site about the sustainability of aluminum.
Dave, as one of the people at SigmaDek intimately involved with the development of the product since its inception, I'd like to address your comment/concern vis-a-vis noise when walking on an aluminum deck substructure. This matter was dealt with very early on in and thouroughly addressed in our risk register. We engineered a proprietary clip which results in a very robust and secure relationship between the deck board and our SigmaDek substructure. It also provides a much quicker installation time which will be appreciated by the person doing the actual construction. SigmaDek was designed to be deck board neutral thus allowing the consumer to choose the look and features they preferred in a deck board along with the integity of the SigmaDek substructure. Having walked on numerous SigmaDek test decks, I can assure everyone that there is NO perceptable difference in the sound between a wood constructed deck and the SigmDek substructure. I would invite anyone to visit our website www.sigmadek.com to further their understanding of our unique system and attendent benefits as well as view a timelapse video. Thanks everyone for your very encouraging comments and look forward to SigmaDeks immanent launch.
This is a great example of a material option that might be overlooked simply as a result of convention. Most decks are made of wood simply because most decks are made of wood, not necessarily because it's the best material. As engineers, we should constantly be challenging this type of thinking. Maybe the material which is conventionally used is the best one, maybe not - what are the pros and cons? Engineering education is supposed to encourage this kind of critical thinking; how often it succeeds in that goal is probably a question for another thread.
One issue which I didn't see discussed in the article was noise. Obviously a noisy deck could be a nuisance to a neighborhood. Rain on an aluminum deck would sound very different from rain on a wooden deck. Even walking on the deck with hard shoes could be loud depending on how it is designed. These issues could be addressed through testing and simulation.
I'd also like to see a detailed cost breakdown. I could imagine that the lifetime costs of an aluminum deck would be lower due to the lower amount of maintenance required, but would like to see what the numbers say.
Another interesting question would be the environmental impact. Is it possible that aluminum is actually the green option? After all, it is a recyclable material.
Finally, as a metallurgist, I'd like to know more about the castings. Some photos of the castings would be nice. I'd also like to know the alloys used, surface treatment, etc.
Overall, this is an interesting article which will hopefully get engineers thinking about non-traditional material options, not just for their decks. This is exactly what I read Design News for.
On April 21, NASA launched a novel project, putting into orbit three satellites that employ an off-the-shelf commercial smartphone as the control system.
The legacy endpoint devices that control our critical infrastructure (utility systems, water treatment plants, military networks, industrial control systems, etc.) are some of the most vulnerable devices on the Internet.
In a switched-capacitor filter, capacitors and switches take the place of resistors and accurately reproduce the characteristics of continuous-time Bessel, Butterworth, and elliptical filters.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
10 
