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TOPIC: Product Selection

Best value Stone coated Steel Roofing

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Hi, I am replacing wood shakes. I am reviewing several types of stone coated steel shake roofing materials. Can you advise what is considered the best value stone coated steel roofs between the following and why: -Decra Stone coated roofing -Gerard Stone coated roofing -SteelROCK stone coated roofing Why would I select one over the other? I have a bid for Gerard vs. SteelROCK They are very close in price. I would appreciate any reviews/guidance/experience of the 3 noted roofing materials. Thank you in advance.
Kathleen McIntee

10/3/2014
Kathleen, I have used one of those 3 manufacturers with success but I cannot speak personally about the other 2. The best roof is the one that is installed correctly. How do the installation companies compare?
Eric Novotny
An informed customer is the Best Customer!

10/4/2014
Having used all three I would go with Decra or Gerard then Steelrock. The first two have been around the longest and imo have a better coating than the Steelrock does. So in terms of coating technology I think Decra and Gerard have a leg up on Steelrock. I am sure the warranties are all the same. All three are manufactured in So Cal... Gerard in Brea, Decra in Corona and Steelrock in Oceanside. You probably could pick the profile you like best and be fine with either of the three companies, but i do feel the coatings on the Decra and Gerard are better, they have been around much longer than Steelrock. The greatest product will only be as good as its installation. Make sure you find a contractor that has been factory trained and has experience.
Guest User

10/6/2014
I agree with Eric and Andy. After product selection the most important thing is the contractor. I recommend that you get three references and contact them. Make sure the homeowners were completely satisfied with the contractors work. The cheapest initial price is usually the most expensive in the long run.
Dick Bus

10/6/2014
Replacing jumbo cedar shake roof also in Denver. Insurance company totaled and acknowledged that existing roof is a superior roof at shedding aircraft noise.Ins co told us to put in supplement if needed. Cannot find a GC roofing co that knows how to replace the roof with like kind ans quality roof as is the standard in every residential and commercial policy in the US. In areas near high noise zones like airports, like kind and quality includes replacing the roof that is likely to be reasonably close approximation of the roofs ability to shed aircraft noise and rain. I cant find a general contractor roofing company that knows how to do that. All companies that promised absolutely that the proposed new roof would be quieter than the old roof,and then finally admit they have no clue how to build a roof that is likely to roughly perform as well shedding aircraft noise and don't know how or who to get help from. The companies want me to be the general contractor, do thier homework, and then they perform the role of a subcontractor and get paid for the job of a general contractor. Crazy! Surely some GC roofing company is capable of acting like a GC and can find out or knows what combination of products is a rough equivalent and has contacts with manufacturers and roof acoustic engineers to know how to replace one of the most common roofs in the US, jumbo shake cedar. Several neighbors have had their homes re roofed with far inferior noise shedding roofs. They also were promised also that the roof would be much quieter but in fact massively inferior, far less that the roof quality that was required by their insurance policy. It's simple to measure before and after noise sheding performance of a roof with the absolute results there on paper if thats needed. Typically you just build a pre-engineered known equivalent but I cant find a GC roofer who knows how to work with roofing professionals to design and build a simple replacement roof.
Guest User

12/29/2017
What does the existing roof consist of again? Noise attenuation is not rocket science by any stretch.
Eric Novotny
An informed customer is the Best Customer!

12/29/2017
Nick, as far as the transfer of airplane sound from the outside, it seems to me like much more sound will come in through your windows and walls than will ever come in through the roof system. In most cases, trying to control sound transfer through a metal roof has to do with concerns about rain noise. Trying to control that noise is very different from what you're trying to do, I believe. Personally, I would look to increase insulation on top of your ceilings in your case.
Todd Miller
Isaiah Industries, Inc.

12/29/2017
Again it's a old growth jumbo cedar shake, they type often used for low frequency aircraft noise attenuation. Jumbo cedar shake is well known for it's ability to eliminate very low frequency aircraft noise because it acts as as an acoustic array or base trap. Have not metered above and below roof but roof likely has an OITC of 45 with strong low frequency attenuation. The brick exterior has the typical 45 OITC. Brick and mortar are also known to have extremely good low frequency attenuation. Combination laminate windows and storm windows in 12" thick brick wall is acoustic laminated glass with storm windows, 4" gap , with OITC of 40. If new roof isn't like acoustic kind, will show up instantly. New growth cedar shakes don't last as long and are not allowed by code. Have full replacement and code upgrade rider. Lots of insurance $. HOA requires 2218 level 4 50 yr roof architectural products. Realtor says will likely be difficult to sell homes near airports in 10 years without a like quality noise attenuation roofs as more and more Americans learn of WHO research showing how bad noise impacts health and learning.
Guest User

12/29/2017
If the attic is ventilated and the roof is solid deck, you shouldn't have any issues with noise. Look at upgrading the insulation levels in the attic with some loose fill cellulose (denser than Fiberglass) and put covers over all the recessed light and other envelope bypasses. If the roof is solid deck, the noise can come through a vented style attic under the soffits and through the assembly that way.
Eric Novotny
An informed customer is the Best Customer!

12/29/2017
I checked with the Canadian Research Bureau IBANA ( Aircraft noise/ home exterior reduction project ) models to get more metal roof noise information. http://nparc.cisti-icist.nrc-cnrc.gc.ca/eng/view/fulltext/?id=b516cfdd-0170-4427-9532-77daf90974d5 . It shows noise transmission through 100 structure types. Steel roofing pg 59 to 63, and they are only showing 1 to3 decibel reduction for ridge or port vents vs no vents. Low level aircraft frequencies were not significantly impacted by more heavier insulation but the mid and higher level frequencies were. You are likely right the plan will likely include more dense attic insulation but that won't be enough. Near airports, it's the very low 10 to 500 hertz, aircraft noise that's the problem. Many main rotor lower harmonics are at 18 to 50 hz. The research does not identify a brand or type of metal roof.enough to tie it to any specific product. IYou have to be a roofing company or engineer to get the IBANA CALC software that creates a solution.
Guest User

12/29/2017
Lower frequencies are especially difficult to get out. Couple of observations from your link that are worthy of note: 1. What are your current insulation levels? The link notes an R20 as a minimum. 2. Fiberglass (loose fill blown in) is about as terrible a sound isolation insulation that there is. Cellulose is much denser than loose fill fiberglass and the additional density will help here. If the sound is moving (as it does) via vibration through the assembly, I would recommend that whatever roof material you go with be installed over a set of battens and possibly cross to allow for some additional airspace (good for low frequency). I would also recommend air sealing prior to insulation installation. If you were going to get real fancy about it and are not terribly worried about the wind lift resistance, you could incorporate some rubber isolation or, at minimum, green glue between the cross battens to help with the sound break. Might not be a terrible idea to look at some deck above deck insulation board prior to the battens.
Eric Novotny
An informed customer is the Best Customer!

12/31/2017
The methods you listed are in the books. Turning that general information into a specific roof build plan is the jump I can't get done and the roofing companies Ive contacted don't know how to do. What methods, data bases, engineers or resources do General Contractor roofing companies typically have in their "trades" group that is used to reliably calculate or what pretested combinations of brand name materials will reasonable likelihood, plus or minus, result in a new roof of "l like kind and acoustic quality" replacement roof. In acoustics , impossible for anyone to create exact duplicate, even with new same kind materials. Been told in commercial roof acoustics for hospitals, using a product mix that is likely to produce the same generally equivalent level is the standard. Can't find any GC roofing company has the skill "trade" to specify a roof build for anyone to build. Delivering a deliverable roof design to build appears to be a steel roofing grand canyon that most roofing companies don't know how to cross. Can't find an engineer or roofing company that knows a professional or engineer, or pretested sloped design that can give me a replacement roof to build. Many of my neighbors believed a roofing company and received far less than like kind acoustic new roofs. More than willing to use even an an out of state resource professional that can spec the replacement build for a jumbo cedar roof. Running out of time on depreciation. Does anyone know of any steel roof company that can has the "trade" to spec a replacement roof?
Guest User

12/31/2017
Well...STC in roof assemblies and not usually a consideration for most of the roofing contractors out there. You have the general data here, I suggest you talk to and installer and see if they can incorporate some of these design features into the product installation. I would say to hire and STC engineer, but I think you have all the data points here already. If we are ultimately trying to get to a STC 45 (i.e. match the walls), that isn't hard based on what you have looked at. Step 1: Air seal and insulate the attic with at least R-49 combined depth and use borate only cellulose. If you haven't already air sealed and insulated, this is a good thing for fuel saving regardless of roof STC. Step 2: Pick a roofing material that you like. Steel and possibly stone coated steel is a great choice if you are trying to mimic the shake look. Step 3: Pick a contractor that can install said material. Talk to the material supplier about your STC concerns and see about employing the air space, cross batten, and possibly rigid foam deck layer as part of the assembly. At that point, you will have all the points of addressing noise as it pertains to Mass - Airspace - Thickness. At that juncture, the weak point is the venting of the roof. Be sure to look at some sort of screening/mesh for the ridge vent if you currently vent that way.
Eric Novotny
An informed customer is the Best Customer!

12/31/2017
Your ideas are the most thought through. After having discussed it, I am still on the start side of the Metal Roof Grand Canyon. HOW DO YOU FIND A ROOFING COMPANY THAT WILL ACT AS A GC? WILL BOTH PROPOSE A DESIGN -- AND--- TAKE RESPONSIBILITY FOR THEIR WORK IN THE CONTRACT TO DELIVER AN APPROXIMATE PROMISED ACOUSTIC1/3 OCTAVE GRAPH PERFORMANCE OF THE ROOF, +- 15% OR BETTER? Measuring exact 1/3 octave before and after roof acoustic performance is very simple. All schools, hospitals , nursing homes all require specific acoustic performance for 15 years. All GC companies will suggest a design- as long as the home owner contractually takes on all GC risk should the GC's design fail to perform. The problem is finding a roofing GC roofing company has the "trade" , likely an experience professional or their consulting engineer, that enables them to deliver sloped roof acoustic performance reliably enough to take contractual responsibility for their promised roof performance work. Proposing a roof design and taking contractual responsibility for that promised 1/3 octave roofs performance remains the GRAND CANYON of the residential metal roofing industry. Does any one know a roofing company that, like all the school and medical offices and nursing homes roofing contracts, is competent enough, has the trade skills, to PROPOSE AND TAKE CONTRACT RESPONSIBILITY for delivering promised acoustic residential sloped roof performance? All my neighbors were promised and paid extra for equivalent performance and and 90% received far less.
Guest User

1/1/2018
Based on the requirements of your performance, I would suggest that you contract with an acoustical specialist and then have them work directly with the roofing company to either build some small models to test the performance and/or verified performance after installation. I would start with your HOA/neighbors and see how many are interested in a solution and then look at contracting with the roofer and acoustical engineer to defray the costs of the engineer over the possibility of the several homeowner projects. With regards to the performance, I can see no reason why the performance would degrade over the course of the years. There isn't a real consumable aspect to any of the materials that have been mentioned so far.
Eric Novotny
An informed customer is the Best Customer!

1/1/2018
Appreciate the professional advice. The time, cost and risk of each homeowner learning to becoming their own roofing GC and hiring/ assembling trades, a roof acoustic engineer is $10,000 and the cost of a steel roof is another $15,000 over TL modified asphalt. With greater risk and a $25k cost differential, with no steel roof company willing to guarantee even approximate, predictable acoustics of steel roofing, there is no choice. The first steel roof company that builds pre acoustic tested structures, like GP did for it's Densdeck product will own the steel roof market. Then, like GP, roofing companies can just have the residential customer select one of the manufacturers pretested structures and eliminate the $10,000/ home cost that acoustic professionals charge each homeowners. Suddenly that steel roof company's roof delivers pretested acoustic results without the $10,000 engineering charge. Without a steel roofing company that can deliver reliable predictable results with steel roofing, Heavy, triple layer asphalt is the only product that roofing companies are now delivering reliable good acoustic steep sloped results with. I don't see steel as viable when heavy modified asphalt, although shorter lived, predictably delivers acoustic results for $25k less and no steel roof company will stand behind their acoustic results work. Hopefully in 20 years the steel roof manufacturers and their installing companies will be willing to build and take responsibility for acoustic build results of steel roofing. Appears In 2018, I'm 10 years ahead of the reliable, predictable aircraft noise mitigation results from a Decra, Gerrard or Steel-rock steel roofs.
Guest User

1/1/2018
Sounds to me like there is a segment, albeit small, of the roofing industry that could be filled by someone with some skills and knowledge that you have mostly already acquired. Roofing companies are going to be far more concerned with panel durability, storm resistance, coating technology, etc. Seeing as there plenty of information out there on STC of insulation and you have posted a link that claims that very little comes through vents, you can safely assume what the STC of your attic assembly is. I would highly recommend some upgraded insulation and Air Sealing and you never quite shared what that number was that was in your attic. After that, there is documented evidence of STC/OITC in metal wall construction that could easily be extrapolated to have application value here on the roof. If you employed some of the same ideas that we have discussed, you could rightfully assumed a certain STC/OITC performance value out of the roof which would only be in addition to what is in the attic. I do not know what and how you would add the two assembly values to arrive at a total value, but there are some examples (i.e. staggered stud walls) that would provide some inclination of what that value might be. Obviously in the case of a truss framed roof vs. a staggered stud wall, there is an acoustical "bridge" in the truss webs, but those are quite small surface areas relative to the area of the attic. The mains of the attic are quite isolated at that point with the considerable insulation. https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwifp-CKrbnYAhUEZN8KHdxtALUQFggnMAA&url=http%3A%2F%2Finsulationinstitute.org%2Fwp-content%2Fuploads%2F2015%2F12%2FMB315.pdf&usg=AOvVaw0coNhYPYbdt6Z7eeBf9qeQ
Eric Novotny
An informed customer is the Best Customer!

1/2/2018
Kathleen, having specialized in stone coated steel for over 20 years, I would like to comment on your question. In the past few months, Boral, the huge concrete tile company, has bought the company that owns both Gerard and Steel Rock. They are both made in the same plant in Oceanside CA, where Metro is also made. The Gerard plant in Brea was sold at least 1 1/2 years ago and the manufacturing equipment moved to Oceanside to the Metro plant. The same company ( Boral) owns all three brands. The products are all similar except for some differences in the actual design of the profile.
Guest User

1/2/2018
The metal siding and roof publication listed 2 above is informative, but offers STC and OITC only. Adding up STC and OITC data, both of which exclude 50% of the highway and aircraft noise problem frequencies will similarly be 50% off on a steel roof noise solution. For roof aircraft noise STC and OITC both greatly over state human perceived acoustic mitigation. The FAA and DOT confirms that ACTUAL TOTAL NOISE, not low frequency excluded definitions or volume understated definitions including STC, OITC or dbA, correspond to noise human perception, complaints and annoyance. STC and OITC are valuable when selling noise mitigation products as they overstate their effectiveness vs human perception. Many infrasonic frequencies between 10 to 20 hertz can't be heard by humans outside but are physically felt and can create tremendous noise inside the building from harmonic and standing wave noise inside the building. Employee productivity loss,sleep loss, student learning loss and greater health costs correlate to TOTAL noise, not STC, OITC or dbA. Most problematic truck, equipment and aircraft noise is below the 125 hz STC exclusion limit and and below the 80 hz OITC exclusion limit. The term dbA, ironically used by the FAA, under reports low frequency aircraft noise by up to 95%. To get very high sound remediation performance numbers, STC and OITC both conveniently exclude the most difficult to mitigate noise and include very large ranges of the easiest to mitigate noise frequencies. The result is a far less expensive product with higher STC and OITC numbers to give a false impression of greater noise reduction than human's perceive. STC and OITC although an indicator, is not relevant to the 100,000,000 million people that live near highways, industrial area and airports. The air alone or the minimum code required thermal insulation alone mitigate most of the STC and OITC higher spectrum noise without any acoustic consideration. For the metal roofs of 100 million in the US, ONLY a 1/3 octave graph of 10 hz to 2000+ hertz frequencies will in a relevant manner describe how their metal roof / under layments mitigate noise and it's detrimental impact on sleep, learning ability and employee performance. Metal roofs last much longer making the acoustic planning need far more critical. The US market is now 10 years behind the developed world in valuing, demanding quiet roofs. Nations around the world increasingly require acoustic performance tests after a re roof to continue /receive an occupancy permit. Steel roof purchasers today must include quiet roof performance so they don't loose value in a future sale. When the US market catches up to most of the developed world, and understands the huge economic cost of noise in offices, homes an schools, quiet roofs will sell for a premium of the remaining value/life of the roof. The US is 10 years behind the world in population density. As density rises, the average person lives in a noisier environment. For 100 million in the US now, at their offices or homes, noise rains on their roof 300 times more frequently than actual weather. making the steel roofs acoustic performance as or more important that the weather performance. Many insurance adjusters have instantly doubled or tripled the offered settlement said to send supplements when the acoustic performance of the roof is mentioned. Most adjusters don't know acoustics so they offer more cash. Many roofing companies are leaving millions of insurance cash on the table by not replacing "like kind and quality" acoustic performance when replacing no longer meets code older higher mass asphalt roofs and also out of code, old jumbo cedar shake roofs that were clustered around airports because they mitigated low frequency highway and aircraft noise. Does an accumulated "Best Practices" body of information/ knowledge in the steel roofing industry , from roofers who have solved or tested these aircraft, highway 10 hertz to 125 hertz noise problems and know how to specify specific brands and products to build the expensive steel roof under layments that the insurance company is legally bound to pay thee costs of. Many insurance adjusters don't want to pay $10k for an engineer so just pay a well documented supplement.
Guest User

1/7/2018

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