Couple Insulation Installation ?'s

[Augus7us]

Hey Gang,

I'm about to start installing insulation in my shop. Its a pole building but I installed 2x4 stud walls in between the posts. My posts are 4x6 so I'm using R19 batts.

I've never hung insulation and I've been watching some videos and had a couple of questions for you guys.

The first is do I or should I do anything with the electrical boxes? Should I spray foam them prior to installing the insulation? I watched a Matt Risinger video or him applying spray foam to the back of job boxes. The house was a mansion and this is just my shop so I wasn't sure if this was overkill or not? Obviously the R factor is going to be lower behind the job box vs the rest of the wall.

My other question is about installing the insulation. My walls are roughly 12' and most of the insulation is unfaced. Maybe I'm just worrying to much here but I feel like gravity will, over time, cause my batts to start to sink in the stud bay. Am I just worrying here or is there something I should do to prevent this? No blocking in the stud bays. All the videos I watched were of shorter 8' walls in houses or there was blocking in the walls.

I'm sure I'll have a few more before I'm finished with the job. Thanks!

 

[Kaizen]

If you can use faced batts it’s a little easier. But no they should not fall if you framed right. Push it in and then pull it out even with stud.
Split the batt in half. Well pull the front off the back. Slip the back behind the box and wires. Cut the face around the box. Seal what you can. Even for a garage those penetrations add up.



Sent from my iPhone using Tapatalk

 

[meboatermike]

If you have the time, energy and money it can't hurt to spray foam behind the boxes. They tend to always seem colder or let in drafts/infiltration it seems. Good luck -- the extra steps now taken will continue to pay you for the life of you using it.

 

[matt_i]

I silicone-caulked all of my electrical boxes for air sealing reasons. Took awhile and sort of gooped it on in places but those are a big leaker in my opinion. There is a product (sort of like a cardboard box that's pre-formed) you staple up and fill with spray foam that encapsulates the electrical box. I didn't buy those, opting for the silicone instead.

The next step is to seal around the OD of the box where it passes thru the wall, before installing the cover plate.

 

[Augus7us]

Thanks for the replies guys.

I went ahead and caulked the boxes Like Matt mentioned this afternoon. I really anticipated it being a pita but it wasn't as bad as I thought it would be. I'll check it tomorrow and make sure it didn't goop onto the floor.

So is there a proper way to seal around the box as you mention, Matt? You'd think the would make something for that.

 

[scottydosnntkno]

Thanks for the replies guys.

I went ahead and caulked the boxes Like Matt mentioned this afternoon. I really anticipated it being a pita but it wasn't as bad as I thought it would be. I'll check it tomorrow and make sure it didn't goop onto the floor.

So is there a proper way to seal around the box as you mention, Matt? You'd think the would make something for that.

They make foam gasket cover plates. But they only seal to the wall not the device itself so it still leaks.

And honestly, it’s a garage. If you heat it, opening the OHD a couple times probably let’s in way more cold air then all the electrical boxes do even without caulking/foaming them

 

[Augus7us]

Yeah, I do get that. Well sort of, its my shop and its detached so I don't see the OH door being used much in the winter.

My thinking is more about how I want to keep an ambient temperature above freezing. I imagine every little thing to seal it up is going to help me keep the propane costs down.

 

[Kaizen]

They make tuck tape for sealing a vapor barrier to boxes. Don’t think I’ve seen it in my stores though


Sent from my iPhone using Tapatalk

 

[K'ledgeBldr]

The best methods and what to look for...

Do some searches for- sealing for blower door test. This will give you plenty of things to look for and ways to handle it.

When it became more mandatory my insulation contractor used vapor barrier tape to seal receptacle boxes to the kraftpaper backing of the batts. Fire caulk in stud holes, expansion foam for wall plate and corner framing (non- California corners), etc. Fire rated foam for between floors/chases, etc. Getting a high passing number on a blower door test can be nerve-wrecking! After about 50, you get ahead of the learning curve!