Roxul in Basement Ceilng

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gggvan

Member
Dec 6, 2012
134
Hello,

I have decided to install Roxul safe and sound in the bays of my basement ceiling for mainly sound proofing. Basement is warm and dry otherwise. Do I need to cover it up immediately, is there any health risks to not covering it for a few months?
 
Hello,

I have decided to install Roxul safe and sound in the bays of my basement ceiling for mainly sound proofing. Basement is warm and dry otherwise. Do I need to cover it up immediately, is there any health risks to not covering it for a few months?
I think on the bag it says it's an irritant and to use PPE when installing. If undisturbed for a few months it should be ok. It's nothing like fiberglass!
 
As long as you strap it up good you should be ok.. Its fairly heavy compared to fiberglass so may need a few extra straps to hold it into place
 
As long as you strap it up good you should be ok.. Its fairly heavy compared to fiberglass so may need a few extra straps to hold it into place
Thanks, should I use metal straps as normal? My bays are 9", and this stuff is 3". From what I read it should work to keep noise down. Any testimonials?
 
It works well for soundproofing and is a good insulator as well. Doesn’t burn or melt. Continues to work after drying from getting wet.
 
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As long as you don't disturb the insulation you will have no issues.
 
Thanks, should I use metal straps as normal? My bays are 9", and this stuff is 3". From what I read it should work to keep noise down. Any testimonials?
There are screws with large washers made for installing rockwool and stick on spikes available as well.
 
As far as risk of exposure Roxul is pretty benign. While placing it overhead I'd suggest using an air mask, gloves, and eye protection just for the particulates that may fall down. I've used it a lot and don't find it do be very irritating to skin though FG tears me up. Roxul can be a little crumbly. For sound control it may actually help to hang it low in the bays creating an air gap above. You may be able to use the little spring wires to support it.

As far as soundproofing you may want to check these out: https://www.finehomebuilding.com/2017/03/28/building-soundproof-walls
and https://www.hearth.com/talk/threads/insulating-the-ceiling.175936/
 
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Does anyone have any tips for installing around recessed lighting? I have the type that are insstalled to rafter faces with 4 legs.
 
Does anyone have any tips for installing around recessed lighting? I have the type that are insstalled to rafter faces with 4 legs.
Is your concern the heat or just general installation?
 
Check the label on the fixture. If it states that it is IC(insulation contact) rated, then insulation can contact the fixture. If it is non-IC rated, typical clearance to insulation is three inches, but check with the fixture manufacturer.
 
Is your concern the heat or just general installation?

just geneal gotcha's, like going around recessed lights, heating pipes, electrical boxes, etc. i'm doing this mainly for sound transfer. i plan on putting a thin, 1/4 or 1/8 wood panel over it installed on those steel frame hangers that separate the panels from the joists bt 1/2" to break the contact.
 
just geneal gotcha's, like going around recessed lights, heating pipes, electrical boxes, etc. i'm doing this mainly for sound transfer. i plan on putting a thin, 1/4 or 1/8 wood panel over it installed on those steel frame hangers that separate the panels from the joists bt 1/2" to break the contact.
It cuts well with a serrated bread knife or insulation knife. its actually a bit like bread in that its somewhat friable and may fall apart if roughly handled.
It worth noting that most if not all recessed lighting fixtures have an over-temp protection. Packing Roxul around these fixtures may make the fixture overheat and trip the temp protection. The Roxul is safe at those temps.
 
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Does anyone have any tips for installing around recessed lighting? I have the type that are insstalled to rafter faces with 4 legs.

You can build boxes that give the necessary clearance around non-IC cans, or search “tenmat cover” at the retailer of your choice to find a pre-made rockwool dome that can be put in the attic, though you may not be talking about an attic at all.

Have you done LED retrofits in the lights?
 
Those fixtures are IC rated with a 15 watt max LED module.

thanks, i am currently using 9w led's. Just took out to check and i could not feel a bit of warmth around the the whole unit or lamp.

my real issue is with how to place the roxul. here's what i'm thinking: i'll go up the legs with the longer bat, then i'll cut smaller pieces to stuff into the inner part of the fixture. just filling the spaces between the fixture and the joist so it's flush with the joist face.
 

Nice! Insulation contact air tight LEDs. When we moved into this house in Texas we had 24 non IC cans, and more than half still had incandescent bulbs. The others were CFL. Thankfully most that we could check did have rock wool covers, but we’ve retrofitted them all. It was awkward, though, because they were different types and needed different solutions.

Someone else will be better able to comment on your insulation strategy, but remember when your talking about stuffing insulation somewhere that compressing it makes it lose r-value.
 
Nice! Insulation contact air tight LEDs. When we moved into this house in Texas we had 24 non IC cans, and more than half still had incandescent bulbs. The others were CFL. Thankfully most that we could check did have rock wool covers, but we’ve retrofitted them all. It was awkward, though, because they were different types and needed different solutions.

Someone else will be better able to comment on your insulation strategy, but remember when your talking about stuffing insulation somewhere that compressing it makes it lose r-value.

Thanks. I'm not concerned with R value, 64 in basement year round with no treatment, except dehumidifier. I have an insert in the fireplace down there. But I didn't mean actuallty mean stuff, place a better word.
 
Thanks. I'm not concerned with R value, 64 in basement year round with no treatment, except dehumidifier. I have an insert in the fireplace down there. But I didn't mean actuallty mean stuff, place a better word.

So, I saw this yt video where an installer put 2 Batts in the cavity, 1 up against the upper floor and then 1 at the joist face.

Is this overkill? this installer does say this is necessary to meet Canadian code for apartments.
 
So, I saw this yt video where an installer put 2 Batts in the cavity, 1 up against the upper floor and then 1 at the joist face.

Is this overkill? this installer does say this is necessary to meet Canadian code for apartments.


That sounds like one of dozens of ways to meet a specific number or value of sound transmission. The code is likely the specific number and not necessarily the method employed to achieve it. Although it's usually a good idea to know whatever entity/local governance will be stamping acceptance as they may have specific interpretations of what "code" compliance is.

Even for fiberglass insulation if this is storage and not a living space and the insulation will not be disturbed it doesn't have to be covered.

When I was looking at Roxul ( I think the name has been changed to Rockwool now ) they had these plastic straps like box strapping to hold it up with screws .

I'm considering Roxul for a crawlspace but the joists are different distances apart and not necessarily parallel. So a lot of measuring and cutting. Some have been sistered to address some nasty plumbing butchering.