Wood Battens vs. Dimple Mat vs. 3D Mesh: Matt Risinger Comparison

[@bellaherna1]

Again how do you adhere to manufacture install instructions of having to apply to wood decking but you need to ventilate with conditioned attic - how would you be able to ventilate it then?

[@bellaherna1]

how does the mesh or shark wrap adhere to manufacturer install instructions of applying directly to sheathing - also won't this added layer cause oil canning issues?

[@dannyortiz5520]

What if the roof /attic space were foam insulated? Would you still need mesh or strips ?

[@kermitefrog64]

This is a great video. Unfortunately it is difficult to get some of these products from a Local Home Depot or Lowes.

[@alexanderspriggs6028]

This has to be one of the most curious roof systems I’ve ever seen or heard of.

[@rdotjdot12.3.]

Is the coravent also installed at the roof rakes?

[@rob8823]

What are your thoughts on if one were to use the Viper cdx product on top of sharkskin across a low slope roof? 3/4 ply base, 2" polyiso with radiant barrier applied above, sharksin, viper, then metal.. I heard you say it does not meet the gap thickness for radiant barrier but I dont want it that thick and also believe that a little will be much better than none? What about issues at the gutter edges, or would I need to use a different product for insect rejection? I like the idea of airflow underneath, added radiant barrier distance, and possble sound dampening benefit. Thanks for your channel!

[@atmueller]

Giving this question some attention. I was wondering the exact same thing

[@clarencehopkins7832]

Excellent stuff bro

[@cxsey8587]

Then how are you supposed to ventilate the roof? One of the assemblies isn’t warrantied and the other assembly isn’t a large enough gap

[@IKonMann]

Curious if VentGrid with a vapor permeable Mento5000 WRB could be a solid option too?

[@MaryMargaretBryarly]

Who is your roofing contractor in the Austin area?

[@asm101]

Watched the whole thing great video guys!

[@TheMetalRoofingChannel]

Awesome! Thank you! -Thad

[@zhugeliang777]

What kind of dimple mat is that? Will any dimple mat do?

[@dewholdingsllc1050]

What is your solution? You do not say best practice for 3/4" to 1" metal roof air gap above the deck if the two products you covered are not thick enough to space metal roof panels above the deck. You do not sound to like fir strips to create air gap. Again what is your solution for creating 3/4" air gap?

[@DeepakBhat]

Here I have confusion about ai foil, ai foil-faced downwards side here but as I know it should face towards sky side because ai will reflect 97% of the RH. (radiant Heat) the air gap is mandatory. I don't doubt it, but he can face that ai foil towards sky side but he didn't, why? Is there any specific reason? Don't say emissivity will work here. :P As I know for heat, it faces towards the sky side, for a cold its face towards the downside.

[@sunshine5349]

they totally screwed up! but even if they did it correctly that fiber mesh material is touching the hot metal panels and the foil radiant barrier so some heat is transfereed between the 2.

[@renalshomlmes338]

Shiny side does indeed go down. The radiant heat (ir) will go through materials (shingles, metal, osb) so it goes through the non shiny side, then hits the protected shiny side that is back to the non shiny side and is reflected up towards space. You will get a contact patch with the special underlayment but it is 5-10% instead of 100. That in turn helps with conductive heat transfer as well.

[@budmanzoom4441]

The only issue I have is the wood 1x4s. They rot. At minimum I would water seal them but I like to rip down 1xX composite boards and use them for the air gap.

[@JakeOfALL]

Great Video !

[@TheMetalRoofingChannel]

Glad you enjoyed it! -Thad

[@byarbrough002]

So Matt said he can do furring 1x4's because not in a coastal environment. What would you suggest for a Galveston house :-) Thad, what product does NOT "negate the engineering."

[@TheMetalRoofingChannel]

To adhere to manufacturer's engineering, you must attach your panels to the same substrate as the original testing. For example, if the manufacturer tested a panel over 1/2" plywood, you also then would have to install over 1/2" plywood. From there, several factors will infer your decision on which panel and material you choose including distance from saltwater, slope of your roof, and local codes/engineering requirements. Do you have a contractor already selected for your project? -Thad

[@byarbrough002]

@@TheMetalRoofingChannel I don't have a contractor yet. I'm still at the stage of studying local codes, including approved roofing products for our high wind area. Thanks for the feedback.

[@TheMetalRoofingChannel]

Understood! The right contractor will be able to help you with local codes and product selection as well. Here is a free checklist we created to help you ask effective questions when you start getting bids: bit.ly/contractor-questions-checklist You can also reach out to our Sheffield Metals team and ask for a contractor referral in your area: bit.ly/contact-sheffield -Thad

[@sunshine5349]

just use white metal roof with SRI 75 which is 2 to 4x more heat rejection than "trendy" black roof in this video. then no need to spend thousands on strips and labor for gaps. Saves you money in the long run too because less insulation is needed.

[@bellaherna1]

how do you allow for venting if manufacturer requires install directly onto sheathing AND you have a conditioned attic - building in southwest Ms so basically same climate as Texas @@TheMetalRoofingChannel

[@appl314]

Could you comment on nexcem durisol icf blocks? So much effort is taken for moisture proofing and thermal blocking that their breathable product seems counter intuitive.

[@kyledean6659]

Right on Sunshine

[@dorhocyn3]

Mr Matt is a belt , suspenders, elastic waste band , draw string and ..... duct tape (if it’s a fluid Appliable product in a sausage tube)

[@mattkov6505]

matt always use 2x4 for lathe almost same price

[@timrich6755]

Why the diagonal 1x4?

[@TheMetalRoofingChannel]

That's been Matt's preferred way to do it for years, you can probably find more information on his reasons over on The Build Show channel. The downside of installing them diagonally is that you don't get as much airflow from eave to ridge because many of the diagonal battens start or end at a rake. -Thad

[@asm101]

Best practice is to install a double strapping system, first layer vertical and second layer horizontal...

[@wim0104]

@@asm101 yup, and that double batting system makes it easier to install the radiant barrier, and the roofing.

[@TheMetalRoofingChannel]

@Architectural Sheet Metal Yes, agreed on the cross-hatch method. That allows the eave to ridge air flow that I mentioned. -Thad

[@acdnintheusa]

@@TheMetalRoofingChannel Just to confirm that I am understanding the details correctly, would the double strapping method would still likely void the engineering on the metal roof?

[@mr.eastcoastgrow6132]

Some say to put the metal right to the decking some say perlins I can't get a straight answer

[@TheMetalRoofingChannel]

Drop us a line here and someone from the Sheffield Metals Technical department will be able to help: bit.ly/contact-sheffield -Thad

[@LuminairPrime]

Two things: 1) the description of the radiant barrier doesn't make sense (pointing the reflective side away from the sun), and 2) if the dimple mat and 3D mesh products don't support above-deck ventilation, and the furring strips are out of spec, then that means no above-deck ventilation product was shown. Time for another video!

[@MikeShannahan]

I did some research. Sharkskin is CA based company and this is their largest market for radiant. The CA 2022 Energy Code describes the barrier as an attic feature, not something above the roof deck: "RADIANT BARRIER is a highly reflective, low emitting material installed at the underside surface of the roof deck and the inside surface of gable ends or other exterior vertical surfaces in attics to reduce solar heat gain." In Appendix section RA4: "the radiant barrier shall be securely installed in a permanent manner with the shiny side facing down toward the interior of the building (ceiling or attic floor). Moreover, radiant barriers shall be installed at the top chords of the roof truss/rafters in any of the following methods: (a) Draped over the truss/rafter (the top chords) before the upper roof decking is installed. (b) Spanning between the truss/rafters (top chords) and secured (stapled) to each side. (c) Secured (stapled) to the bottom surface of the truss/rafter (top chord). A minimum air space shall be maintained between the top surface of the radiant barrier and roof decking of not less than 1.5 inches at the center of the truss/rafter span. (d) Attached [laminated] directly to the underside of the roof decking. The radiant barrier shall be laminated and perforated by the manufacturer to allow moisture/vapor transfer through the roof deck. (e) In addition, the radiant barrier shall be installed to cover all gable end walls and other vertical surfaces in the attic."

[@sunshine5349]

Radiant shinny barrier should NEVER touch the metal roof! It should also face the sky, not the house's interior. Come on, you guys are over thinking this ! shinny side reflects heat, other side doesnt' do jack. Air gap needs to be between heat source (metal roof) and radiant barrier. please take down this video and upload a corrected one. how can 2 pros mess up the basics so badly!

[@gone2dmtns]

Common logic would support your conclusion. I was reviewing the LP Tech Shield radiant barrier product and they also specify the shiny side down. If anyone knows the reason I'm sure a bunch of us would like to know why.

[@gone2dmtns]

@ManiacallyYours Attics are not made to be conditioned spaces. If anything you would want to keep the heat out to avoid condensation.

[@elliottdiedrich3068]

When you bake a potato and face the shiny side of the tin foil to the potato, it cooks significantly faster than the other way around. The same principle applies to a radiant barrier; you face the shiny side to where you want the most heat to remain or stay out.

[@mr.g937]

@@gone2dmtns The guy in this video (Risinger) always does conditioned attics

[@jodibridges570]

Thinking about my child’s lunchbox… shiny side inside keeps hot things hot when I want and cool things cool when I want… of course not at the same time. I conclude the radiant barrier facing toward the inside of the structure will do the same.. so long as I have a way to either heat or cool the inside of the structure. Seems to me it will reflect back in what is going on inside. Just call my idea the “insulated lunchbox theory.” I think it makes sense.