3 (little known) Benefits of Rockwool Insulation

Matt and Travis Brungardt tour the Experience Center at the Rockwool Factory in Ranson, WV. Learn about some of the little known benefits of Rockwool insulation and stay tuned for a factory tour to see how it's made.
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[@JohnathanBach]

I first learned of the superior benefits of Rockwool from you, Matt. Yes, Rockwool is more expensive than fiberglass, but the superior R-value, water repellant benefits, sound properties, and fire blocking benefits make it hands down the better option. I have insulated my first house completely with Rockwool, and I will never put fiberglass insulation in my house projects ever. Thanks Matt!

[@buildshow]

100%. Thanks Johnathan

[@douglaskern4256]

T r t. RThe t t

[@MrJimme2003]

Having had a house fire that actually started outside on the porch, caught the Styrofoam insulation behind the siding and was funneled up into the attic you better believe I plan to spring for this stuff when I finally get to build. If it Rockwool had been used it would have been a nuisance that was cleared up in a couple weeks. Instead I'm still dealing with the fallout 3 years latter.

[@JohnathanBach]

@@MrJimme2003 Man! So sorry to hear that. I hope you can soon get back on your feet. Prayers.

[@MrJimme2003]

@@JohnathanBach Thank you. I like to think I'm getting close. Not sure when it will be exactly, but everyday has to be closer right?

[@davidhoover2446]

I am an audio engineer - for anyone who doesn't know, 2" insulation absorbs down to about 500Hz, 4" thick down to about 125Hz. If you use acoustic panels with an air gap behind them or as baffles, you double the efficiency of the absorption generally speaking. Safe n Sound 3" works pretty well, but double that up to 6" to start absorbing frequencies under 100Hz. Their product is 3" thick usually going in a 4" stud bay and the air gap helps absorb more sound, however it is a trade off because 4" of insulation absorbs to lower frequencies.

[@voidisyinyangvoidisyinyang885]

Perfect info - that's what I was really wondering about. Thanks so much. I'm off a super noise highway. I already get good sound proofing but I want even better - so this is what i needed to know. Also the insulation and fireproof value and keeping out animals. This stuff is awesome.

[@frostman9661]

That's great info! However, what do you do to start blocking really low frequencies from a subwoofer? Such as 25-50hz?

[@bassplaya69er]

@@frostman9661 mass and isolation to block external low frequency ( or any noise TBH). Rockwool absorbs noise so it's great for acoustic treatment when uncovered / covered in breathable fabric or slotted panels. While Rockwool in your Walla will stop more sound than nothing, a better strategy to block external noise is multiple layers of heavy wall cladding, each layer mechanically isolated from each other. Alternating studs, using Every other stud for external cladding, and the other studs for internal with the studs staggered so there is an air gap between the external cladding and an internal stud for example. Double or tripping up on the thickest plasterboard you can get, or even splashing out for the noise blocking plasterboard and still doubling or tripping it up, and bonding each layer to the one before will give you a lot of mass. The alternating studs gives you some mechanical isolation. Take it further with isolating joist hangers etc. Still fill the void with rockwool, but make sure there is an air gap between the rockwool and either the external or internal cladding.

[@frostman9661]

@@bassplaya69er that's great info! Thank you!!

[@sapprdaddy]

Thank you. This is what I had wanted to know.

[@Billliamm]

The difference between 80 db and 40 db is 10000x. Not half. Awesome product.

[@SnappyWasHere]

In iowa where I live spray foam is hugely popular. 2” thick is most common. This leaves a huge open cavity in the walls where the wiring is. Electrical fires spread super fast and mixed with the fumes from the foam causes huge problems. After my neighbors shop burnt down due to that very thing I insulated my new post frame shop with Rockwool. So glad I did.

[@crhu319]

I'd never foam around wires. Only around conduits run through walls.

[@lizzieb6311]

Yes… while spray foam is the “sexy” product of the moment I would NEVER use it…not only the fire spread and fumes…but if you get a leak that runs behind the foam on the inbound side of the exterior sheathing or from roofline it does NOT present itself until tremendous damage is done of a major mold issue occurs. Old school “boring” rock wool is a tremendous product.

[@TheBuccleuch]

Love the channel, guys! Clarification on dB scaling - the decibel scale is logarithmic, so for every reduction by 3dB, THAT'S "half as loud." A reduction of 10dB means 1/10th as loud. The reduction noted from 80dB to 34dB would be 0.000025 "as loud."

[@yentrader]

Glad someone caught that. 👍🏼

[@voidisyinyangvoidisyinyang885]

thanks - yeah that rockwool room was super quiet. I definitely have enjoyed the soundproofing and I can't wait to add more rockwool to my structure for insulation also and to keep out critters. This vid has me even more excited about it.

[@bassplaya69er]

Most people including you gets this wrong. 3dB increase / decrease is a doubling or halfing of sound energy, not loudness. A perceived doubling / halving of "loudness" is closer + / - 10 dB SPL for most people (psycho acoustics is subjective) Most non audio engineers would not notice a change in SPL less than 3dB A "doubling" of Uncorrelated noise sources will give increases of approximately 3dB spl - IE 2 trumpets will be approximately 3dB spl louder than 1 Trumpet. 2 trumpets are not perceived as twice as loud as 1 Trumpet. A "Doubling" or correlated noise sources, such as loudspeakers positioned close enough to couple at the relative wavelengths, will give an increase of 6dB spl. 2 speakers are also not perceived as twice as loud as one speaker. A 3dB spl increase requires a doubling of power (part of where the confusion comes from I think) if a speaker is producing 90dB spl at 100W, 93dB spl will require 200w (ignoring power compression and other losses)

[@allenclarke9642]

@@bassplaya69er and then to make things even more complicated the perceived loudness varies depending on frequency

[@bassplaya69er]

@@allenclarke9642 perceived absolute loudness is very frequency dependent and even perceived changes in loudness will vary according to the listeners personal equal loudness contours approximated by Fletcher munson curves. 100dB SPL at 2 - 4 KHz will be painful for most people without hearing loss Vs 100dB SPL at 20 - 100hz that most people will be fine.

[@skrimfisker]

I have used Rockwool here in Norway for the last 20+ years as a carpenter. Great product and fire safety. Great video Matt.

[@ricoludovici2825]

I used it in Germany maybe 5 decades ago. The owner/builder got a deal on Roxul in Denmark and I put it under the tile roof system. Only took 40 years for it to get to the US. Best stuff in the world.

[@GeraldLeenerts]

@@ricoludovici2825 ehh, forget Gutex?

[@ricoludovici2825]

@@GeraldLeenerts If it was expensive or effective, we didn't get it in Iowa. More like Celotex. That was the high-dollar corn-board.

[@aksting]

That sound absorption demonstration was impressive. This would be incredibly beneficial for a home office space. If not every room.

[@PrimeWhoLeo]

The absorption changes again with drywall applied because echoes and reflected waves. Account for this and add surface absorbing materials on the drywall fyi. I used S & S in my home studio in between ceiling joists and walls and it made a great difference.

[@John-lp5xh]

​@@PrimeWhoLeowhat's s&s?

[@georgekg5okf178]

I've Switched out my Pink to Rockwood back in 2016! Dropped my Utility Bill by 1/3!

[@GlueTubber]

I've been using Rockwool for about the past decade to (slowly!) replace the insulation in my house. I put it everywhere, and I love it. Easy install, blocks fire, holds itself in place, deadens sound, superior insulation, won't compress like glass insulation, no off-gassing like foam. It's an awesome material. If I were building a new house, Rockwool would be everywhere.

[@Im-a-machine]

Lebanon, Tennessee. My own DIY home improvement project for 2022. I removed the blown in insulation from my attic. Some places didn't even have any insulation or very little. Then I air sealed all of the penetrations with spray foam. Then I used Rockwool R30 insulation batts, and a second layer of the batts perpendicular to the ceiling joists. In effect I should have an R60 now for my attic. I can already tell a greatly improved comfort feeling within my house. Now that the summer months are here, lets see how the utility bills are for A/C. I'm really enjoying the Rockwool insulation!!!! Thank you Matt!

[@ceciliabora8589]

Where did you get the Rockwool? I'm near Lebanon and coming close to needing insulation on my build.

[@voidisyinyangvoidisyinyang885]

Yeah I did two layers on my roof - just a hut - still now I just need to do more on the walls.

[@Im-a-machine]

@@ceciliabora8589 I bought mine at Lowe's in Lebanon. It's not normally in stock, due to supply chain issues I guess? But I wanted R30 batts, so I ordered it at the Pro desk.

[@greggshaw7936]

I did this in my garage attic. Also framed out the garage walls flush to the concrete and insulated both voids with Rockwool. Garage was always cooler than the house ( with A/C ). No windows in the garage or garage door. Whst does that tell you about the impact of windows ? Very nice to work in even on hottest summer days in Regina, Saskatchewan.

[@alexisstarsmith1477]

I worked as a S&H warehouse position in an insulation supply company. We supplied. Rockwool & I loved it! Best insulation ever, I didn't get itchy, I could lay all over it - OK unlike fiberglas! I learned it was superior to fire unlike fiberglas! I fell in love with rockwool. Now 40yrs later I learn it's bug proof - just amazing+!

[@tonyramberg9697]

I can assure you it's itchy. Still way better than any other insulation

[@wendya1580]

When we were getting work done on the house--new havoc and abatement of old ducting--we realized our blown-in insulation was about 3" deep. That was it. We wanted our 30 year old romex gone (the old knob-and-tube wasn't connected anymore). For that, we wanted the pitiful insulation gone--had it vacuumed out. We put pieces of subfloor up in the attic so the electricians could move around up there, and made sure they put in some lighting, as there's a lot of room up there. Once they were done, we needed to re-insulate. My husband saw your channel and other sources touting Rockwool. Our local Home Depot put it on sale, so we were getting pallets-full at decent prices. We weren't so worried about hitting R39. We laid down R15 between the joists, shoving it in to very narrow spaces and building it up to the right depth, and up the side gables. No need for baffles as no overhang, which is not uncommon in our neighborhood. A second layer of R12 went on, perpendicular to the first, over all areas where the subfloor pieces were not going to stay. At the edges of everything went a third layer of R12. On a 100F+ day, our interior ceiling went from 98F (no insulation) to 78-80F (with insulation). One area only got one layer so far, because of work that had to be done, is about 85F. It is far easier to cool down a house that is 80F than one that is almost 100F. And it was EASY to instal! And Rockwool had a monthly drawing for "best review"--which I won! $200!

[@kipcarroll5644]

50 years ago my family was blowing Rock Wooll into houses attics and walls. Great stuff. Never had one problem with it. My dad did presentations where he melted a copper penny in his hand packed with Rock Wool.

[@gramos9115]

I have just finished, even moved in , to my new timber framed house and was so reassured by this video as we fitted Rockwool inside and outside of the whole structure, including the roof . The wind is howling outside yet inside is a sea of tranquility . we used rigid outside then silicone colour coat rendering on top . I taped every seam , edge and joint to keep it airtight and we live without heating . I used 100mm XPS under the wood floors to keep us off the slab , so no underfloor heating needed. I struggled to get builders to understand the theory , now they want to know how to do it and would I fit an off grid system for their clients ! Rockwool is such an amazing insulator I even filled the interior walls with it and it helped create a peaceful interior .

[@staberdearth3130]

I worked with a number of Rockwool manufacturers over the years. Some made fireproof acoustic ceiling tiles (regular paper based tiles are not used in commercial environments) some made Rockwool batts. Interesting process, waste slag from metal melting processes is melted along with additives to control viscosity and melt/transition temperature in a shaft furnace (induction will not work for non conductive materials like it will for melting metals) and the molten product is fed to a spinning wheel (think cotton candy machine). The melt is spun off and has a leading shot head and a long tail which is blown into a large room or container, the shot upon cooling usually breaks off, falls to the bottom and is recycled to be melted once more. The Rockwool is gathered and processing into batts. The acoustic tile process involves adding color,usually whiteners and a clay based binder pressed out like dough, given a desired surface finish, cut to dimension then baked in a continuous oven. This process was how I knew it from over a decade ago, it may have evolved to optimize the process over the years.

[@royrobinson4636]

Great video! *Rockwool is the best investment in my home to date! 🥰 One of my major goals for our home is to be as energy-efficient as possible, to the point of being energy independent. Our yearly climate can range from 120f in mid-summer to 20f in mid-winter. Heating and cooling costs are rising fast and are becoming a major expense. Simply replacing the fiberglass insulation in the attic with Rockwool insulation has reduced my heating/cooling costs and energy consumption dramatically! I've also recently completed a 300 sq. ft. room addition/office space in the garage using Rockwool in the walls and attic. I have also noticed the improved noise reduction! *Rockwool has been a game-changer in my home! 😎

[@Tahu2323]

just put rockwool in my garage. Its gonna be a fabrication shop so I was really worried about fire resistance. Covered it in sheetrock and after watching this video I feel I made the right choice! Thanks for these videos!

[@virgil3241]

Love this stuff, as a homeowner, and far from an expert, this stuff is so awesome to work with. Ease of cutting and fitting and installation. I have bats like this in my furnace room roof for just some sound dampening. And because it doesnt have fibres coming off, it can stay there unfinished

[@bobbys2160]

This product rocks. I've used this in my floors, walls ceilings and the heat and noise disappeared. plus I like the idea that a electrical short in the walls would essentially snuff the flames. Another bonus I notice no bugs migrating from the floors or walls. Rock on

[@Publicname6570]

just had an ADU (granny flat) buit. i installed rockwool safe and sound in the bedroom/living room wall myself to counter television noise. SUPER easy DIY product. i regret not specifying it for the rest of the build.

[@bf6159]

I was introduced to this product via marketing and promotions. I live close to a Highway, too close. Because I had to take the place down to the studs, I opted to got with this product for both exterior and interior walls, it made a profound difference. I see the traffic and feel the large vehicles, but I don't hear them anymore unless I'm in the garage.

[@KarelSeeuwen]

Hi Matt, it is great to see a channel like yours dealing with well insulated long lasting buildings. I live in Japan and it was a major headache trying to find builders who were competent in using the materials and techniques that you present. I had to hire an architect to design my house, because none of the the housing construction firms knew or were willing to use anything but the standard Japanese system which hasn't changed much in over 100 years. I hope you can convince more people to put in a little more up front for the long term benefits it will bring. Best of luck. Karel

[@TheLatinMass]

Great info and glad to see Travis representing KC again like he does at the builder symposium at BLVD Brewery the last few years. It’s good to see builders who genuinely have an interest in better building science, construction techniques, and an overall better home!

[@robertbrodarick9607]

Matt, love your approach to informing the masses. Together with Travis you connect us with a full gamut of feature benefits. Your enthusiasm for these type of events and keen eye for curation help us learn so in a conversational way that bypasses a sales pitch. Here's to hoping the algorithm spreads more of these type of videos and you get more exposure! Thanks for the expert level content.

[@wayneeden98]

Rockwool has got crazy awesome engineering built into it, it's really a no-brainer in my opinion

[@BBKConstruction]

Killer content. I’ve been using rockwool for a little bit and there are so many benefits. Easy to cut, easy to work with, and far superior over traditional fiberglass.

[@alwaysrockn2009]

How’s the weight of the product compared to cellulose or fiberglass? Does it cause a problem if it’s used in a ceiling?

[@georgevue8175]

Cool video - I built a plywood box to cover my emergency generator and lined it with 4 inches of Rockwool. The Rockwool fireproofs it and helps it run much quieter.

[@justincoleman4133]

I've just installed 100mm of RW45 (UK spec, u-value 0.035) in between 175mm timber joists on my new flat roof extension. It's a warm roof construction with 120mm PIR for thermal insulation (yes has a VCL) and is covered in a 2mm poly membrane. The difference the Rockwool has made is truly spectacular. It's so good I wish I didn't have to cover. We're using the room before it's finished and after a few hours of letting dust settle feels great and breathable as Matt explained. Really great product.

[@bassplaya69er]

If you like the acoustics of the room with the uncovered rockwool, you can make up panels wrapped in a tight weave flame retardant cotton and hang from the walls / ceiling. Get art printed on canvas to improve WAF factor.

[@PoeRunCraftProvisions]

Matt, I can't believe you came to West Virginia and didn't stop by for a tour of our build! I've tried to apply "all reasonable" Build Show techniques to our on-a-budget-in-2022 BarnBuild. That's OK, I understand. Thanks for all the info over the years!

[@mesatex]

Matt, great video with the Rockwool plant. I have been using Rockwool since 2008 when we had to special order it from Home Depot in Arizona for our home. That is when we learned how much better it performs than our 1987 Centex home's paper faced batt... after that I got Rockwool into a property for a Phoenix area Catholic charity. Next we will be using Comfortboard on our first exteriors in Metro Houston. When allowed, I spec/ buy Rockwool for projects I work on.

[@godman5043]

My goodness, Rockwell answers so many of the problems that come with using older types of insulation. Rockwell will probably be the insulation I use in the remodel of my house.

[@RecordingStudioLoser]

I use this all over my studio. Love it.

[@scrivyscriv]

I had no idea the value and benefits of rockwool until I started watching these videos. I'm currently finishing out my second story, starting from just a bare floor that was never finished out during the initial build. It took a bit of time to get the rock wool batts, they are a special order item at the blue home store and impossible to get at the orange store. I believe there is about a three fold difference in price between fiberglass and rockwool! It installs just as easily in real life as these videos make it look. Last week I placed my sheetrock order from a local building supplier, and knowing I would need more insulation down the road, I asked the supplier if they carried it... He responded that I was probably in the 1% of people in the area that used it. It's hard to figure out when someone is giving genuine advice and recommendations, or if they are just repeating the status quo.

[@Californians_go_home]

Why are you buying at a box store? Go to an insulation supplier. If you aren’t a BoT

[@scrivyscriv]

@@Californians_go_home I don't know any insulation suppliers. If I find someone local I would prefer to use small business for the next phase of the build

[@XS-ss7go]

In my opinion rock wool is best insulation ever invented

[@mikefranks4528]

Great chemistry between you guys. Explanations never skip a beat. Thanks for a great presentation. I will be installing rockwool in my van for the awesome insulation, safety (fire resistant) and, of course, sound proofing.

[@billjohnson7347]

Great video. I own a 70 year old home in the PNW. There isn't any insulation in the wall cavities. I'm going to install new siding and at the same time remove the sheathing, insulate from the outside, reinstall the sheathing and install the new siding. I'll be using Rockwool to insulate it.

[@euroasiabtlimited3208]

Love it . I also now only use and recommend Rock wool . I love the open flow insulation system . Building in climates that are hot in the summer and cold in winter , open flow is the only way that a complete open vapor flow without condensation problems . Lime and builders sand mix for renders is another great way for exterior finishes . It can be coated onto a expanded metal mesh .

[@morrishowell7410]

I have to agree that this is the only home insulation on the market today. Regular fiberglass insulation should be outlawed. Cutting in around electrical outlets alone makes this so much more efficient as well as wiring in the walls, ect. The cutting of this insulation with a knife alone makes installation much easier, the particles do not hang in the air, and as you install it, you can hear the noise level drop. It is more expensive, but you are actually getting the return on your investment, very rare in today's world. I really can't say anything else other than the fact that it is harder to get, but it is worth the extra effort. Finding it at Lowe's or Home Depot is not easy. Find an old lumber yard in your town that still works hard for your business and have them order it in for you. You will be amazed by this product if you use it. And thank you Matt for educating us on this product, I would have never come upon it without your videos.

[@huntera123]

What a great video. Mineral wool is the better insulation choice. It doesnt burn. It isn't ruined by water exposure. It is sound deadening. Bugs and rodents hate it.

[@kaiyack]

Rockwool is also used in hydroponics. Same company. However, the horticulture version is made in The Netherlands.

[@TommyAlanRaines]

My new home will actually use Rockwool!

[@Murrdogg]

Love the details, especially that basement interior

[@firemanj35]

Wow really great suff Matt. Thanks for the info

[@thompson4620]

Quality insights as always, thanks!

[@johnhufnagel]

I have plans to close the envelope of my attic soon, and one of the issues constantly coming up is moisture buildup under the sheathing, and that fiberglass insulation will prevent air movement from drying out that sheathing. sounds like rockwool is the answer to that problem.

[@enriquealdogarcia4850]

Hi, many thanks!! it was really a completely didactic video. Many thanks

[@michaelmcewan5074]

Awesome Video! Just the information I need for a huge project in my own home. Thanks Matt! Great info, I truly appreciate it!👍

[@zefrum3]

Interesting! Thanks for the material review

[@robertrada4783]

I’m glad the US is finally catching up to the rest of the world. Was using rock wool in recording studios….. decades ago.

[@MichaelM-to4sg]

Rockwool is a trademarked brand of mineral wool. The primary vendors in US are Roxul, the makers of Rockwool, and Owens-Corning, makers of Thermafiber. Of those 2, we only use Thermafiber unless constrained supply chains limit us to Rockwool. Thermafiber is marginally less $$ but the determining factor is Rockwool employs formaldehyde as binding agent. Thermafiber is certified formaldehyde free. We and our clients prefer best air quality available, that includes using building material w/o formaldehyde whenever possible

[@BobPritchard]

I switched to Owens Corning Thermafiber because Rockwool refuses to pull out of Russia after their invasion of Ukraine. Unethical company.

[@kjohannes6896]

@michael m Interesting! How do both rockwool and thermafiber compare to Johns manvile temp control mineral wool? I thought there were distinct differences between rock wool and the general mineral wool in what it’s made from?

[@MichaelM-to4sg]

@@kjohannes6896 Never seen JM mineral wool. Is it formaldehyde free? Rockwool vs Thermafiber are both types of mineral wool insulation. Other than the formaldehyde binder, I don’t know the exact chemical differences. Technically, both are fireproof rated and have same R-value of 4.2/inch

[@JamesCusano]

It was only back in 2017-2018 that Thermafiber started offering versions of their products manufactured without using formaldehyde, and it was at the same time that Rockwool started offering the same. There has been some debate as to whether the alternative versions are even necessary, since the amount of heat used to create mineral wool seems to burn off any formaldehyde used during manufacturing. Good to have options, though.

[@MichaelM-to4sg]

@@JamesCusano Formaldehyde is used as binder to produce the batts and sheets of Comfortboard. It is not used in the molten rock phase. Roxul claimed they too were eliminating the formaldehyde, using a different binding agent. I do not know what happened to that product. As of 2021, the MSDS published by Rockwool for ComfortBatts, SafeNSound and Comfortboard 80 all list levels of formaldehyde.

[@RafaelSwit]

I’d love to replace current insulation with Rockwool. @Matt Risinger any chance you might make a video for DIYers with existing homes (not a new build), on just how to make insulation and moisture barrier upgrade, without ripping off the roof? Including information and options for various parts of the country would be amazing.

[@benkranz59]

On a job 2 years ago and all the interior insulation was stored outside in winter for reasons unknown to me. By the time we needed to insulate we lost 10s of thousands of dollars of fiberglass insulation and only had to throw away 2 bag of Rockwool because they were full of mud

[@bradkubota6968]

Mice WILL burrow into it. Blew my mind. Bastards tunneled in my newly refreshed small addition up a 7ft wall and across an 11ft length of ceiling. They tunneled better than Guzman. Still a big fan of this over fibreglass. DIY tip. I run my electrical at the same length as the bat lengths if possible.

[@FredMcIntyre]

Awesome stuff Matt, thanks for the info! 😃👍🏻👊🏻

[@TheSpatulaCity]

Love the stuff. Wish it was cheaper though.

[@MrDavrosPatel]

Another great informative video Matt! Would love to know more about the Fiberglass Z Girt product mentioned in this video as well as the black faced comfortboard. Thanks.

[@karlhungus545]

Did my entire house with ROXUL way back in 2009. Fiberglass is peasant insulation. Have a look at how much better it stays in the wall cavity 10 years later too...no slumping.

[@tccdlinux1471]

Excellent, I learned a lot. Sure makes me push foam to a smaller roll.

[@ricoludovici2825]

I just about came unstuck with that display of the Comfort Board over wood studs. I am building a vacation house in the WUI above Las Vegas - cold/dry climate. I did a LOT of research because nobody in the County building department had any idea about 1) full basement, 2) unvented attic, 3) fire-resistant construction. The house is next to a deep/steep ravine with mountain fir and pine trees and low, dry vegetation. Coming from SoCal, I truly understand about fire. I specified all fireproof and fire resistant materials on the outside. Where they are not fireproof, like the glulam beams, they get covered with fiber cement board to match the Hardie siding. Walls are covered with OSB sheeting [NOBODY has any idea about ZIP panels, not engineer or building department], ZIP-taped sheeting seams, Tyvek [builder put up to keep dry while waiting for the 7 month backorder of my Comfort Board]. Then we put up 1x nailers with Hardieplank over them to finish the outside. I felt pretty good to see that first display of the wall system. That is exactly what I ended up with through my research.

[@voidisyinyangvoidisyinyang885]

yeah I had no idea Rockwool can replace any kind of vapor insulation material. That was probably the best info in this vid.

[@ricoludovici2825]

@@voidisyinyangvoidisyinyang885 What I got was that Rockwool does not trap or hold the vapor. Hence no need for vapor barrier. However, I still wonder about this. Because if the outside is 15* and the inside is 72*, somewhere in the middle it will be 32*. Still seems to me that there will be ice formation.

[@JamesCusano]

@@ricoludovici2825 There's a section in the 2021 IRC book that details the different continuous insulation R values needed for different climate zones to reduce or negate the need for a vapor retarder.

[@ricoludovici2825]

@@JamesCusano I have the 2021 IRC. I broke the back at the climate zone section and the insulation section, making copies for the county plans examiner [a 54 year old woman from Calcutta who had never built a house]. Since this is a cold/dry climate - Zone 5 - I didn't bother with the vapor barrier. It was a lot more important in Minnesota, where I lived before.

[@micahwilson9346]

You talk about this protects against wildfires. This also gives it the added benefit of being protected from neighbor houses on fire. A lot of neighborhood fires spread to multiple homes because of being densely packed.

[@Kybossls]

Matt, I hope you are reviewing this video, my question for you or anyone with knowledge. I am remodeling a 1973 house with rock wool, 50 years old no bugs or wood damage. This rock wool has paper and then they installed plastic before the sheet rock. I’ve opened up the outer walls for the remodel. Should I remove the old stuff and replace with new, had thought about spray foaming the walls, however you have educated me with the rock wool. There is a little paper damage from moisture, not moldy but a little change in color. Thanks in KY

[@kf5hcr176]

I built our house with 8 inch metal studs and had the walls insulated with rockwool, The insulation installed was $4k by Bob Mutina from west Columbia, TEXAS, fine man by the way, and we recouped that within two years of very low electricity usage. We have four central ACs and our electric bill was $100-$190 per month. The utility company has changed our meter three times as they figured a 5000 sq foot house should be using more power. My question to you experts is: I have an uninsulated attic, fully decked, how can I lay rockwool over the decking and still be able to walk upon it? Are the insulation boards dense enough it will support a man's weight without being distorted? Thanks for the fine presentation. Take care

[@chevy7698]

Great Video.. I bought this product based off your reviews on it , Thanks

[@brucecampbell6133]

An important dampening mechanism of the safe and sound in the "maze" is the sound attenuation on the surface of the insulation; killing the echo (like an anechoic chamber). Once the wall is covered with sheetrock that mechanism is eliminated and the main benefit is sound dampening through the wall.

[@Wolfiecolada]

i love rockwool. it's difficult to find many rockwool products in my area but there are 2 products here so far, 2x4 walls 16" OC and the comfort wool that is a little thinner, about maybe 3 inches thick or 2 1/2 - 2 3/4 inches thick. i hope they start carrying more locally. only available around here at lowes far as i know.

[@jjb3406]

Incredible! I sure could use this in my 1910 farm house.

[@henrycarlson7514]

Interesting , Thank You. I need to get some

[@Quietcold007]

This was good. Rockwool rules.

[@Prorex1911]

I live in Abilene where we just had over 10k acres burn in the hills. Our 1968 house ( I remodeled with Rockwool from watching you back in 2017/18) was about a mile away from one that started a month prior to this last big fire. One lady who is a nurse lived in her family’s house that was passed down and it all got burned without insurance. I’d love to talk with you Matt if you ever come to Abilene. I’d love to help her out but I’m not in the position to do so financially.

[@Casmige]

I just got through doing a Rockwool between the wall stud remodel. I put so much Rockwool into the remodel?,a 1900 ft.² 3-bedroom was finished out at 950 ft.² We put insulation on the back of our insulation and then insulated that for good measure... Can never have enough insulation...

[@ricoludovici2825]

I hope you staggered the joints.

[@ericwotton2046]

I found rockwool to keeps out radiant heat much better than less dense fiberglass. It does come at a cost in my area but installing it you can tell the difference.

[@savydude1]

Love it. But the products are hard to get in Canada.

[@daviddunsmore103]

Any idea why that would be? You'd think that it'd be ideal in our climate, where insulation values are more critical, in addition to all the other benefits. 🤔

[@macrapidito1]

Hi! I'm renovating a 100 YO double brick walls home located at PA, USA and Rockwool is my go to insulation how ever my only question is... Is rockwool an Insulation that is open to vapor diffusion? open to vapor diffusion is = to say Vapor permeable? does somebody has an answer to this question? Do I have my answer at minute 2:10 ? Thanks in advance for your help

[@GM8101PHX]

I design houses as a hobby, the exterior walls start with 16x8x4 colored concrete block with colored mortar so painting is not necessary, then 1 1/2 thick Kevlar 8 x 4 panels with aluminum facing acting as the vapor barrier, then steel framing 2x6 packed with Rock wool insulation and finally 5/8 inch Drywall panels pre painted on the interior face with fire retardant paint prior to install, then the exterior (seen) face of the drywall gets the same paint which comes in any colors you choose! My assumption is this would be a fire proof building. Even the interior walls are insulated and paint treated as the wall is constructed. The block is grouted every 32 inches with rebar re-enforcement inside and around any windows or doors! High strength security doors for the exits and hurricane roll shutters for all windows also makes it very safe from home invasions!! The windows would be bullet resistant glass, the doors would be Master Security Doors which keeps any bullets fired at it and withstands over 93 sledge hammer blows without penetration!! Would it cost a bunch of money ? Yes, but it would withstand hurricane force winds. The wall framing is welded together along with roof trussing known as Perfect Wall Inc. Fire treated lumber is used inside the steel framing for doors, windows and the kitchen where cabinets will be hung. In my current home I used 1/2 inch plywood to start on the wall so the cabinets would screw into the plywood even they do not hit any studs. A whole house 20k generator would give consistent power even if there is a major power failure supplied via a 1,000 Gallon diesel fuel tank underground and with a 10,000 gallon potable water tank buried under ground. Why the extreme prep? I worked in my local county jails and inmates told me how they get in to your home during a home invasion!! I went home and took care of any issues to harden my home. I have been told I have a fortress of a house, with the strong security doors, block construction and security doors. I also have flood lighting all around and cameras so I can see outside with the shutters closed!!

[@scorpio6587]

I have been wanting to learn about below grade rockwool, especially exterior.

[@buildshow]

I’m looking forward to using it below grade on a future project. The anti-termite benefits are fantastic

[@Hedgehodge-]

@@buildshow do you happen to have a link to the study they did pretty please :)

[@tedspens]

I never thought about I joist webbing being more combustible. I'm going to recommend Rockwool to my clients.

[@JoeTopinka]

Thanks for the great video. I have a 100 year old English Tudor revival in the blue ridge mountains of North Carolina. We are wondering if we should use rock wool in the attic space above the coach house. We have a slate roof which is original and wonder if we should place the rock wool in the cavities between the roof rafters and also should we place an air vent against the roof sheathing first and then install the rock wool?

[@connbyrn]

Matt maybe it’s cause I’m 29 and almost there myself if not already am but I’m loving the gray in the hair

[@Darrell_Coquillette]

I put this in my shop walls. But I've been trying for the last six months to get some for the attic. I can't find it anywhere. When will I be able to have heat and cooling in my shop? Maybe next year I guess.

[@AaronSchmid1]

Anyone else miss the old intro??!?!?!?! I say it for him now! edit: its on the end now? guess i have to watch till the end :D

[@kjohannes6896]

I’d like a video that compares rock wool to other mineral wool competitors. Not a lot of info out there on that and I’d love to learn.

[@r7boatguy]

I can compare it to the stuff from Menards. When installed it seems similar, but the Menards stuff is terrible to work with. I installed some in the ceiling of my basement, and had to wear goggles. It sheds dust and fibres. Safe n Sound doesn't.

[@kjohannes6896]

@@r7boatguy I used the Menards stuff recently too and I had the same experience. Wasn't expecting that.

[@juaneato]

Hi. I live in Florida and own a home that has radiant barrier OSB installed by the builder. D.R. Horton smart home. I was wondering if adding more radiant barrier to the rafters will help cool the attic even more. Eaves and ridge vents.

[@terrybussenger6233]

I live in Northern Illinois, building our retirement house with a GC. If we use 5.5 Comfortbatt in the exterior walls (2x6, 16oc) with 1/2 zip sheathing, do we still need insulation board on the exterior wall and do we need a vapor barrier on the inside? I think in this video you indicate no vapor barrier is needed? Thanks, love your "delivery" of the content!

[@sewersideproductions2606]

All I know is that I used three layers between floors (basically shoved as much as I could in the space) and it totally killed most sounds. I couldn’t hear a Super Bowl party happening upstairs, and any noise that did happen to make it through it sounded miles away. It’s tedious to install and expensive (where I live the price recently jumped about 20 bucks!!), but if a quiet space is important to you, it’s an excellent product. Additionally, ‘Whisper clips’ and ‘resilient channels’ before installing the ceiling panels further improved sound-squashing function.

[@Dave5843-d9m]

Im a big fan of Rockwool. It's literally water repellant and of course non toxic. I dropped a batt into a water barrel. Thinking it was scrap, I pulled it out and threw into the skip (dumpster). An hour later it was bone dry with a water puddle beneath. The water had literally run out. In UK our damp climate causes problems with condensation. If we do not use an internal vapour barrier, warm air will percolate through any insulation and condense within. Loft spaces are OK as they should be well ventilated and insulation is fluffy. Rockwool in a wall is pretty dense, water condensing within wont percolate to the outside so it has to drain downwards. It could leave a permanently wet area at the bottom. Do we know that situation wont happen and how would we mitigate any issues?

[@leo-fs7zu]

Great video , one question, I live in Pennsylvania, if I put Rockwool r23 in attic floor cavity and cover with wood board , do I need vapor barrier under Rockwool insulation? Rockwool does not make faced batt insulation. How can I use Rockwool insulation in attic insulation? I m really appreciate. I can’t find the answers

[@jamescole3152]

You didn't mention under the roof or direct contact with the roof sheathing? Should you leave a space above the rockwool or not?

[@MrTommytwotone]

I worked n a house were the rock wool settled n the studded walls about 2/3 inches at the top plate. I’m wondering it might be a good ideal to put a little adhesive on the wool or wall

[@gavhoffdrums3129]

A house built with this system is gonna be super efficient! Crazy, but definitely gonna make the build more expensive!

Except it won't. Rockwool needs massives amount of fossil fuels to get created in the first place.

[@mankind5709]

One thing they didn’t speak about was using a plastic cover over the rock wool to seal the rock wall under the dry wall. There is a Swiss product that uses a tape that seals called SIGA Majrex

[@tracykaiser7292]

Gut renovating a 1940's era house with stone exterior and interior walls clad in ship lap. I am replacing all windows. I'm concerned about adding insulation to the walls due to moisture build-up in the wall cavities. Is Rockwool a good solution in the wall cavities as it can dry both ways?

[@garysullivan1970]

Matt: love your expertise! Question: Should my attic space over my attached garage be blocked off/walled from my home attic space to prevent the hot air from being over my living space? The space over the garage is uninsulated. The rest of the attic over living space is blow in insulation. I have soffit vents and ridge vents throughout the garage and home. The garage roof faces South and "cooks" in the summer. I live in Georgia.

[@leestebbins5051]

It used to be readily available at the local big box store but no more. Couldn’t get in 2022 and currently 2-3 month back order.

[@johnfitzpatrick3416]

Matt, I mentioned to a well known window manufacturer rep that I wanted to re-sheath my house with Zip system under Hardie board on the exterior. He said (Don’t do it, the zip will rot from the inside out because vapor is trapped. Said older houses weren’t built to be that airtight. If I had closed cell foam in studs in wall cavities the vapor wouldn’t be able to pass through to the Zip/OSB🤷🏻‍♂️ Your thoughts?

[@jefferyeckes5343]

ALL OSB is vapor IMpermeable, which means it does not pass vapor at all, or so little it does not matter. This is due to the glues and resins that hold it all together. Same goes to a slightly lesser degree for plywood. The coating on the Zip system is really just to shed RAIN penetration from the exterior, not vapor from the interior. Plain MDF is a tad better (not enough to be called semi--permeable though), but water resistant MDF is not at all due to similar resins and binders. This particular issue has more to do with whether you are using a smart vapor barrier (like the Intello on the last mock-up) or plain 3 mil plastic. The PLASTIC creates an 'aquarium' between the vapor barrier and the OSB and traps moisture. The Intello allows the moisture to escape seasonally (when temperature profile changes) back into the room. MOST WALLS are not vapor open all the way through, and do not NEED to be! Using Rockwool on an exterior is more about the EXTERIOR drying, than the interior, AND it does not lose R value if it gets wet (yes, it's generally hydrophobic, but it can still allow water to infiltrate under pressure). Again, as long as you do not trap vapor and moisture between impermeable layers, you will not usually have a problem with moisture BTW, we hyper seal and hyper insulate older homes all the time, we just add an ERV (energy recovery ventilator) that exhausts the air in the house through an energy exchange and draws in fresh through a MERV 14 filter (typically recovers 90% of energy). It changes the air in the house more than a few times per day. #BUILDINGSCIENCE

[@johnfitzpatrick3416]

Jeffery thanks for the excellent explanation 👍

[@jefferyeckes5343]

@Steve L Hi Steve, Saying 'I know very little about the value and use of the vapor barriers' would have been more of an honest answer, don't you think? Here is a hint; vapor MOVES in and out of wall (ceiling) assemblies, depending on the internal and external environment. ONLY when vapor is TRAPPED by the WRONG BARRIERS does it become a problem. This is usually due to a LACK OF KNOWLEDGE on how they work. That's just the SCIENCE, regardless of your opinion....

[@jonathanbrenny403]

I'm remodeling my home in Minnesota & looking to add continuous insulation to the exterior to help seal up the home & better the acoustics. In the video you talk about adding a bug screen. What the best bug screen material that you recommend?

[@Iampalindrome]

The display at 4:50 is using a vapor barrier yet they are talking like you don't need one. Can someone clarify here?

[@pattiespinosa4640]

I am planning to use cast iron soil pipe instead of ABS in my two story home because of cast iron's sound deadening qualities. However, if I were to insulate ABS pipe with Rockwool do you think I would achieve the same goal: to not hear water flowing overhead and through walls?

[@DanielinLaTuna]

Hey Patti, that’s a great question!

[@overamped23042]

Wrap your abs pipes with clay sound deadening.

[@maxhunter3574]

Does Rockwool provide any added structural rigidity like closed cell foam insulation? Also how does the fire resistance compares to closed cell foam that has the fire retardant in it?

[@user-dr2pg8fk2i]

Short answer is no on structural. Fire resistances is better because it inherently doesn't want to burn.

[@sctexan5392]

Another planning question; in your videos I see a lot of combinations of insulation. I'm thinking: ZipR on the outside, 2" closed foam inside and some other insulation to fill the remaining cavity. What do you think?

[@kemp7435]

2" closed cell in combination with a 3.5" fiberglass batt is a great combo in 2x6 framing. Depending on your budget you could get R-11,R-13, or a high density R-15. Or use a 3.5 mineral wool batt. If budget isn't an issue and you want max R value just go full cavity closed cell spray foam.

[@sctexan5392]

@@kemp7435 thanks for the input. According to Spray Jones, after 2 inches, the return on investment isn't worth adding more foam.

[@hailexiao2770]

Sounds expensive. Spray foam between studs doesn't get you much better R-value than cellulose, rock wool, or fiberglass because of thermal bridging, and the Zip-R is a great air barrier anyway. If budget isn't an issue I'd just abandon the Zip-R entirely (you have to get the nailing done almost perfectly through 2 inches of foam to get stated shear strength), go with 2x6 & cellulose sheathed with regular Zip, and put 4-6 inches of GPS or polyiso on the outside with cladding on furring strips.

[@sctexan5392]

@@hailexiao2770 interesting, seems to a different recommendation than many.

[@chadms2]

I’ve had problems getting/ordering a non-stocked Rockwool product in the Dallas area. As a homeowner with enough knowledge to be dangerous (this channel has taught me so much), I have been tackling several of my own home improvements. I have been trying to order their ComfortBatt for 2x4, 24” OC walls for some time now. I have an LLC and tried to setup accounts with the sellers and distributors in the DFW area (even those you mention), but they have told me they are too busy for my business. Anyone at B1S or Rockwool able to assist. Take my money!

[@tysleight]

Find a contractor friend and give them a " management fee" and use there accounts on a cash basis. My guy is my former boss that I was laid off from in 2009. He is big enough that he gets huge discounts and like a few grand on a house ( I only do 1 remodel a house every other year on the side).