# New construction recessed lighting



## Northern Electrician (Jun 27, 2017)

Hey everyone looking for some insight on what you install for recessed lighting. I have always installed a recessed housing and a retrofit led trim. Now I see the popularity rising with the canless fixtures. At first I was not on board knowing it would be a pain cutting all my own holes after drywall. But I see they make a canless housing that can be roughed in and drywallers can roto that out. And the J box actually mounts to the frame when installing the light fixture. 

My concerns are if you have to change a light in the future you will have attic insulation raining down on you and when the lights start to fail 10 years down the road will there be a capable replacement? 

What's you thoughts?


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## MHElectric (Oct 14, 2011)

Have you installed those puck lights that look like can lights? They are super slim and almost identical to the look. I think they're even rated for showers. They weigh like 1.25lbs so you can literally mount them to a cut in box and be fine.


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## macmikeman (Jan 23, 2007)

Northern Electrician said:


> Hey everyone looking for some insight on what you install for recessed lighting. I have always installed a recessed housing and a retrofit led trim. Now I see the popularity rising with the canless fixtures. At first I was not on board knowing it would be a pain cutting all my own holes after drywall. But I see they make a canless housing that can be roughed in and drywallers can roto that out. And the J box actually mounts to the frame when installing the light fixture.
> 
> My concerns are if you have to change a light in the future you will have attic insulation raining down on you and when the lights start to fail 10 years down the road will there be a capable replacement?
> 
> What's you thoughts?


Why would you care about what happens ten years down the road , when the builder used so many inferior products in building the structure , like clapboard and chines drywall and the like........ How about them Home Depot doors that warp 2" as soon as the GC or developer is paid off and runs away to Panama....
Love the new fake wood vinyl flooring slats that they use now.... Wait ten years till the plastic gets brittle and cracks apart like how my kitchen floor fake wood did............


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## HackWork (Oct 2, 2009)

Keep doing what you’re doing. Old-fashioned cans are great for open ceilings.


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## 99cents (Aug 20, 2012)

macmikeman said:


> Why would you care about what happens ten years down the road , when the builder used so many inferior products in building the structure , like clapboard and chines drywall and the like........ How about them Home Depot doors that warp 2" as soon as the GC or developer is paid off and runs away to Panama....
> Love the new fake wood vinyl flooring slats that they use now.... Wait ten years till the plastic gets brittle and cracks apart like how my kitchen floor fake wood did............


Because cutting a big hole in vapour barrier is WRONG.


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## 99cents (Aug 20, 2012)

Use a surface mount like a Halo CLD. Hack uses a fixture that looks good but I haven’t seen it in Canada. No big blue box. Use a NuTek gasketed octagon.

If you’re retrofitting a canless light into an insulated ceiling, don’t cut the vapour barrier. It can be done.


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## macmikeman (Jan 23, 2007)

99cents said:


> Because cutting a big hole in vapour barrier is WRONG.



Silly boy, there is no vapor barrier with drywall straight against the ceiling joist....


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## 99cents (Aug 20, 2012)

macmikeman said:


> Silly boy, there is no vapor barrier with drywall straight against the ceiling joist in third world countries....


FIFY :vs_laugh:


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## macmikeman (Jan 23, 2007)

How Dare You!


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## HackWork (Oct 2, 2009)

99cents said:


> Because cutting a big hole in vapour barrier is WRONG.


The vapor barrier is the kraft paper attached to the fiberglass insulation. Cutting it doesn’t change anything. 

In the US when we try to seal the house better we do so on the outside of the wall/floor/ceiling cavity, not on the inside. The vapor barrier on the inside of the wall/floor/ceiling cavity is just for moisture and only used in certain areas depending on the climate.


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## 99cents (Aug 20, 2012)

I thought this guy was from Canada but he isn’t so he probably doesn’t know what I’m talking about.


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## MHElectric (Oct 14, 2011)

What's up with you guys in Canada and vapor barriers? That's like a meaningless word in America.


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## Easy (Oct 18, 2017)

I would prefer to use Old-fashion cans as Hakworks described. The main benefit is that you have more choices for trim. Baffle, Square, adjustable ect... With integrated wafer lights you get what you get.


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## 99cents (Aug 20, 2012)

MHElectric said:


> What's up with you guys in Canada and vapor barriers? That's like a meaningless word in America.


Here’s what I think I know because I’m too lazy to look up the actual facts  :

It was probably the National Research Council that started studying this and, judging from the houses I work on, it goes back fifty years, maybe longer. The VB goes between the drywall and framing. That keeps the moisture from the building away from the insulation. Over the years, rules were introduced to include acoustical sealant, boots around device boxes and fixtures, house wrap, etc. It’s all contained in the building code and strictly enforced.


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## 99cents (Aug 20, 2012)

If we put a can in the ceiling, we need to use a blue boot.


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## HackWork (Oct 2, 2009)

99cents said:


> Here’s what I think I know because I’m too lazy to look up the actual facts  :
> 
> It was probably the National Research Council that started studying this and, judging from the houses I work on, it goes back fifty years, maybe longer. The VB goes between the drywall and framing. *That keeps the moisture from the building away from the insulation.* Over the years, rules were introduced to include acoustical sealant, boots around device boxes and fixtures, house wrap, etc. It’s all contained in the building code and strictly enforced.


It seems like you guys now use it more to stop air movement than moisture.


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## MHElectric (Oct 14, 2011)

Wow, that's crazy. I've never seen anything like that. Do you think it's because the bitter cold??


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## 99cents (Aug 20, 2012)

HackWork said:


> It seems like you guys now use it more to stop air movement than moisture.


Technically yes but the indoor air has a higher moisture content.


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## 99cents (Aug 20, 2012)

MHElectric said:


> Wow, that's crazy. I've never seen anything like that. Do you think it's because the bitter cold??


It’s because of the cold; “bitter” is a relative term. 

It seems to me that some of the states kind of struggle with cold weather housing. Our research goes back a long time and is available to anyone who wants to use it. As tradesmen, we don’t think much about the stringent energy efficiency codes because they have been in place for a long time.


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## Forge Boyz (Nov 7, 2014)

How does the drywall get fastened? I know that sounds like a dumb question, but the glue holds much better than screws do. Do they not glue the outside walls and just use lots of screws?

Sent from my SM-G970U using Tapatalk


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## Bird dog (Oct 27, 2015)

99cents said:


> It’s because of the cold; “bitter” is a relative term.
> 
> It seems to me that some of the states kind of struggle with cold weather housing. Our research goes back a long time and is available to anyone who wants to use it. As tradesmen, we don’t think much about the stringent energy efficiency codes because they have been in place for a long time.


and builders don't want to burn up space & money, so, they make the walls as compact as possible to get the insulation level they need? I mean it would be crazy to put in double walls unless you were forced to.


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## 99cents (Aug 20, 2012)

Forge Boyz said:


> How does the drywall get fastened? I know that sounds like a dumb question, but the glue holds much better than screws do. Do they not glue the outside walls and just use lots of screws?
> 
> Sent from my SM-G970U using Tapatalk


They just drive screws through the drywall the same as any other wall.


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## 99cents (Aug 20, 2012)

Bird dog said:


> and builders don't want to burn up space & money, so, they make the walls as compact as possible to get the insulation level they need? I mean it would be crazy to put in double walls unless you were forced to.


Our standard is a 2 X 6 wall at R20.


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## Forge Boyz (Nov 7, 2014)

99cents said:


> They just drive screws through the drywall the same as any other wall.


Yea i know that. I guess they have to use a lot more.

Sent from my SM-G970U using Tapatalk


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## MHElectric (Oct 14, 2011)

Bird dog said:


> and builders don't want to burn up space & money, so, they make the walls as compact as possible to get the insulation level they need? I mean it would be crazy to put in double walls unless you were forced to.


You know, I never caught on to this until I heard some guys on here (from up North) talk about all that exterior walls are 2x6. I'm guessing it's for the additional R-factor insulation needed.


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## Bird dog (Oct 27, 2015)

99cents said:


> Our standard is a 2 X 6 wall at R20.


btw since I subscribed to Philo, I found Mike Holmes on the DIY Channel. :smile:


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## 99cents (Aug 20, 2012)

MHElectric said:


> You know, I never caught on to this until I heard some guys on here (from up North) talk about all that exterior walls are 2x6. I'm guessing it's for the additional R-factor insulation needed.


That’s the only reason. For a normal house, 2 X 4 exterior walls are okay structurally.


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## Bird dog (Oct 27, 2015)

MHElectric said:


> You know, I never caught on to this until I heard some guys on here (from up North) talk about all that exterior walls are 2x6. I'm guessing it's for the additional R-factor insulation needed.


My understanding is homes will have 2" foam on the outside for energy efficiency with a fiberglass mat & stucco(?) for the final finish.


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## cdslotz (Jun 10, 2008)

99cents said:


> If we put a can in the ceiling, we need to use a blue boot.



What's that all aboot?


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## mofos be cray (Nov 14, 2016)

To expand on what 99 said: we put the vapour barrier between the framing to prevent air with a high relative humidity (vapour)migrating through the wall or ceiling. The problems occur when it encounters a cold surface (such as an exterior wall) and the moisture condenses out of the air within the wall cavity.
The building code up here now specs fully wrapped wall structures which means vapour barrier on the inside which wraps under the sill plate and over the top plate on the inside and a impermeable barrier over the sheathing that wraps under the sill and over the top plate as well. Insulators are supposed to fill holes around wires that enter the wall space and we have gasketed device boxes that are supposed to separate the inside air from entering the wall cavity.


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## 99cents (Aug 20, 2012)

cdslotz said:


> What's that all aboot?


The insulator cuts a hole for the recessed light in the VB and then the VB is taped to the flange on the boot. It maintains the integrity of the VB around the fixture, although it can create kind of a large hole in the insulation.

It’s why I like the thin surface mount LED’s. They mount to an octagon box. The flanged and gasketed box has lots of room for a driver.


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## 99cents (Aug 20, 2012)

Bird dog said:


> My understanding is homes will have 2" foam on the outside for energy efficiency with a fiberglass mat & stucco(?) for the final finish.


It’s usually done on older homes.


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## joe-nwt (Mar 28, 2019)

HackWork said:


> It seems like you guys now use it more to stop air movement than moisture.


One and the same. Moisture can't travel unless the air carries it.


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## HackWork (Oct 2, 2009)

joe-nwt said:


> One and the same. Moisture can't travel unless the air carries it.


You’ve missed the point. If you were to use the same kraft paper faced insulation like we do as you vapor barrier, you wouldn’t have moisture issues just like we don’t. You guys go super crazy sealing things up to stop airflow for energy efficiency reasons.


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## joe-nwt (Mar 28, 2019)

Bird dog said:


> and builders don't want to burn up space & money, so, they make the walls as compact as possible to get the insulation level they need? I mean it would be crazy to put in double walls unless you were forced to.


Not crazy. Your energy costs and heating degree days dictate whether double walls are warranted. 

Not everyone up here is on natural gas for instance. Throw some long winters and -40 into the equation and it turns into a pay now or pay later situation.


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## joe-nwt (Mar 28, 2019)

HackWork said:


> You’ve missed the point. If you were to use the same kraft paper faced insulation like we do as you vapor barrier, you wouldn’t have moisture issues just like we don’t. You guys go super crazy sealing things up to stop airflow for energy efficiency reasons.


I see your point. See my post above. once that moisture hits the -40 insulation it will freeze inside the walls.


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## macmikeman (Jan 23, 2007)

99cents said:


> I thought this guy was from Canada but he isn’t so he probably doesn’t know what I’m talking about.


:vs_laugh: Liar........ 


Google Hotel Dieu, Windsor Ontario. It all started there baby,,,,,,,,


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## Bird dog (Oct 27, 2015)

joe-nwt said:


> Not crazy. Your energy costs and heating degree days dictate whether double walls are warranted.
> 
> Not everyone up here is on natural gas for instance. Throw some long winters and -40 into the equation and it turns into a pay now or pay later situation.


Joe for you in Yellowknife, Canada...pull out all the stops. :yes:


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## MHElectric (Oct 14, 2011)

-40 degrees....

Screw that bro.


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## Funksparky (Nov 8, 2017)

99cents said:


> They just drive screws through the drywall the same as any other wall.



And drive them right through the vapour barrier puncturing it with hundreds of holes all over the house! 
Overall I think vapour barrier‘s are good and I’ve always been super careful when doing any kind of penetrating or fishing in exterior walls/ ceilings to try to maintain it’s integrity. That said, I’ve seen damage that vapour barrier has caused with mould due to moisture entrapment when doing demo on renovations. 
In response to the OP‘s question I have been using this product: 

https://www.liteline.com/20000067-m.../4"-round-led-slim-profile-recessed-downlight

99 probably wouldn’t approve because the vapour barrier is cut through on the ceiling- which is arguably the most important vapour barrier in the home. That said, the fixture is IC rated for insulated ceilings. I’ve checked with the building department and they have no problem with them. 

I put up these rough-in plates, wire in and attach the junction box/driver, and the drywaller‘s can zip them out. Fast and easy to finish. If the ceiling is blown in I put a piece of fibreglass over the plate and hole before I finish rough in. 

https://www.liteline.com/20000317-master_luna-p/low-profile-plates/luna-low-profile-pla

They make a vapour boot for it too, but my supplier doesn’t stock it, and says no one uses them. I would if I had a customer who was really concerned about a super tight building envelope. 

The seal on the light itself is the potential weak link for leakage into the attic/ vaulted roof space, but they seem pretty good and the springs are like rat traps. Am I making a mistake using these? I like not having to worry about joists/ rafters/ trusses so much like with cans. They can go almost anywhere! 


Sent from my iPhone using Tapatalk


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## 99cents (Aug 20, 2012)

Funksparky said:


> And drive them right through the vapour barrier puncturing it with hundreds of holes all over the house!
> Overall I think vapour barrier‘s are good and I’ve always been super careful when doing any kind of penetrating or fishing in exterior walls/ ceilings to try to maintain it’s integrity. That said, I’ve seen damage that vapour barrier has caused with mould due to moisture entrapment when doing demo on renovations.
> In response to the OP‘s question I have been using this product:
> 
> ...


You’re right, I don’t like it. My preference is to use a thin, box mount fixture everywhere. 

I had a customer a couple of weeks ago who wanted old fashioned cans. He said he preferred changing light bulbs over changing a fixture sitting inside a hole in the ceiling. I couldn’t argue with his logic.

I’m really only using Lotus style lights in renos now.


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## Dan the electricman (Jan 2, 2011)

I think I've seen a vapor barrier less than 5 times here. Only in custom homes.


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## zoltan (Mar 15, 2010)

Dan the electricman said:


> I think I've seen a vapor barrier less than 5 times here. Only in custom homes.


What's considered a VB? Is that the plastic layer between the sheet rock and (internal face of a)stud on an external wall?


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## kb1jb1 (Nov 11, 2017)

zoltan said:


> What's considered a VB? Is that the plastic layer between the sheet rock and (internal face of a)stud on an external wall?


I have been wondering the same thing. Different parts of the country have different requirements and interpretation of what a vapor barrier is. I wonder how long the newer homes will last before the wood starts to mold and rot. Tar paper and kraft faced fiberglass insulation has been around for over 125 years. I know 10 year old houses that had to be redone because of improper insulation. Black mold under the plastic. And spray foam is only as good as the worker installing it. Have you seen the skill sets of some of them?


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## Going_Commando (Oct 1, 2011)

If you deep dive into building science you'll find out there are 3 classes of vapor barriers based on permeability. 6 mil poly is a class 1 vapor barrier and doesn't really let any through. Kraft faced insulation is a class 2 vapor barrier, and let's some through, and class 3 (primed drywall) is basically vapor open. In heating climates the humid air is on the inside of the structure, so you want a class 1 vapor barrier on the inside of the structure to keep the humid air out of the wall so it doesn't condense and freeze in the winter, and thaw in the spring/summer and cause rot and mold. Once you are in climates with more interior cooling, the humid air is on the outside of the structure, so you want a vapor barrier on the outside so moist air doesn't drive into the wall cavity and condense once it hits the cooler air in the structure. Your climate zone and the wall assembly is the driver for what kind of vapor barrier you need, and where it should be. Canada is all a predominant heating climate, so they need that poly on the inside of the wall. If you put that poly on the inside of the wall in Florida or Hawaii, however, moisture will condense in the wall cavity when it hits the cooler temperature inside the home and will cause mold growth and rot.


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## kb1jb1 (Nov 11, 2017)

Going_Commando said:


> If you deep dive into building science you'll find out there are 3 classes of vapor barriers based on permeability. 6 mil poly is a class 1 vapor barrier and doesn't really let any through. Kraft faced insulation is a class 2 vapor barrier, and let's some through, and class 3 (primed drywall) is basically vapor open. In heating climates the humid air is on the inside of the structure, so you want a class 1 vapor barrier on the inside of the structure to keep the humid air out of the wall so it doesn't condense and freeze in the winter, and thaw in the spring/summer and cause rot and mold. Once you are in climates with more interior cooling, the humid air is on the outside of the structure, so you want a vapor barrier on the outside so moist air doesn't drive into the wall cavity and condense once it hits the cooler air in the structure. Your climate zone and the wall assembly is the driver for what kind of vapor barrier you need, and where it should be. Canada is all a predominant heating climate, so they need that poly on the inside of the wall. If you put that poly on the inside of the wall in Florida or Hawaii, however, moisture will condense in the wall cavity when it hits the cooler temperature inside the home and will cause mold growth and rot.


Thank you for the info. What would be the best for both a heating and cooling environment? We have both hot, humid summers and cold dry winters. Two months of each.


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