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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Huge thanks to our Show sponsors Builders FirstSource, Polywall, Huber, Prosoco, Rockwool & Viewrail for helping to make these videos possible! These are all trusted companies that Matt has worked with for years and trusts their products in the homes he builds. We would highly encourage you to check out their websites for more info.

[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!

[davidhoover]

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.

[Billliamm]

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

[wendya]

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!

[georgekgokf]

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

[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.

[aksting]

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

[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!

[skrimfisker]

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

[kipcarroll]

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.

[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.

[staberdearth]

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.

[alexisstarsmith]

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+!

[XS-ssgo]

In my opinion rock wool is best insulation ever invented

[gramos]

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 .

[royrobinson]

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! 😎

[Tahu]

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!

[godman]

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.

[justincoleman]

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.