DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   Electrical and Wiring (
-   -   lower heat loss recessed lights. (

coach606 10-19-2006 07:20 PM

lower heat loss recessed lights.
We've got the attic dormered and the plan calls for 10 can lights up there. My contractor mentioned that we should be sure we want the can lights as they will be like holes in the insulation letting all our heat out.

Ceilings are low up there, so can lights are the best option. I noticed there are special lights with a thermal chamber that allows you to insulated right up to it, and then special "trim" covers that reduce heat loss even more.

But of course, they're like $140 each. Is it possibly worth it? My electrician seems to think the can lights would be okay and that you could shove the insulation in around them without the 3" space usually required.

any comments or other suggestions as we make this decision? Thanks.

petey_racer 10-19-2006 07:55 PM

1) Recessed lights are not "holes in the roof" to let "ALL" the heat out. Your contractor is an alarmist.
Yes, of course there will be some heat loss, but not like an open window as he suggests.

2) There sure are air tight cans for $140. They are commercial grade and very high end. You DO NOT need these.
Several manufacturers make standard air tight cans and they are probably $50 with the trim. Of course prices vary by size, volume sold, and especially trim selection.
Halo's Air-Tite H7 housing is around $25-$30 and the trim is about the same.

These cans can be covered with insulation, even blown in.

Square Eye 10-20-2006 12:09 AM

Petey's right, the I/C (insulation contact) rated recessed lights have a thermal shut off switch to keep the temps from building up to a dangerous level. The heat gets too high and the fixture will shut itself off. Using a lower than rated bulb or a dimmer will extend 'on' times by reducing heat.

The commercial units are sometimes HUGE boxes.. Make sure you have room for them before you buy anything. Dormers are often smaller than they look because of the roof pitch and the framing. Measure carefully. There are compact fixtures available with the I/C rating. They usually have a 50 watts maximum rating. A 50 watt halogen light in a dormer is more light than you might think. Also consider that recessed lighting leaves the ceiling dark. Other fixtures reflect off of the ceiling and are much more efficient at spreading the light. It takes more recessed lighting fixtures to make the same light that surface mounts would provide.

inspectorD 10-20-2006 05:02 PM

Ruffle the feathers.....
I don't agree with petty racer at all on this one.
Those cans in the ceiling do loose alot of heat . They ARE not insulated at all and they create heat to make a thermal chimney.
I deal with thermal imaging and heat loss calculations on homes...we call these chimneys.

We also cal them resets(instead of recessed) because that is also what they do when they get to hot.

Ever see a roof with no snow on it in the area of the recessed lights?

I only install them in controlled areas...been doing it a long time.:D

Just my humple.....edumicated oinion.;)

petey_racer 10-20-2006 06:08 PM


Originally Posted by inspectorD
We also cal them resets(instead of recessed) because that is also what they do when they get to hot.

Absoultely not true. Not if installed correctly and with the correct lamps.

Of course they will melt snow on the roof of a cathedral ceiling. They are adding heat where none existed and this heat is inches away from the roof line. Also, in a case like this we are not talking about heat loss. This is heat gain.

I stand by my assertion that good air-tite cans in a well insulated ceiling have much less heat loss than one might expect. Of course there is some as I stated before, but not enough to "let all your heat out".
Besides, in new construction where heat loss is a factor, it is likely that 2x12 rafters are code. These cans are only 7"-8"deep. There is more than enough room to insulate very well around and above these cans.
Things have come a LONG way since the 70's.

I'm not trying to have a pissing match, I'm just trying to justify my opinion.
I've been doing this a long time too. :p

inspectorD 10-29-2006 12:37 PM

Edjimicated disergreement
Again....again and again, say no to the recessed lights in a cathedral ceiling if you know anything about heat loss.
A better way as suggested is to bounce the light off the ceiling.
If everyone continues to use lame trade and building practices because they have been "doin it that way for years",we will not reach energy conservation goals.

Pete, you might want to adjust your way of thinking...give out some better options is what Coach was askin for, not if his contractor who you don't know is a lame brain.

I understand wanting to use cans in some areas, but try to use them in an attic space where you can actually get some insulation around the box. There is no room for adequate insulation in a cathedral roof assembly.(period):D

petey_racer 10-29-2006 12:56 PM


Originally Posted by inspectorD (Post 6394)
Pete, you might want to adjust your way of thinking...give out some better options is what Coach was askin for,

No, it's ok. I'm good.

Square Eye 10-29-2006 03:41 PM

LOL :D Both of you guys!!

Ok, next!

destrukt 11-28-2012 02:08 PM

I had the same issues and was wanting to "tighten up" my house. I have approx 45 6" cans in my home and was worried about loosing heat/cold into attic. I was also worried about heat in the attic (blown in insulation is covering every can).

I found that the Ecosmart 485 LED bulb fixed all worries. It runs cool and does a good job of completely covering up any and all seams which could let inside air into the attic. The downside is that they are spendy (30 bucks). Upside is that like i said they run cool, seal cans, should run for about 30 years before they need replacement and best of all....these puppy's are efficient! about a buck per year to run. :):):)

Wuzzat? 11-28-2012 02:42 PM

To settle this, or not, start here

To decide about lump sum payments vs. continuing energy cost
ask for the payback period, in years. It's a single number or an interval estimate.

All times are GMT -6. The time now is 12:03 PM.