I find a lot of videos of people putting up a radiant barrier but none of them are actually mentioning which radiant barrier they are using and from the looks of it, all videos looks like they are using something thats NOT from AtticFoil. Your the first independent person that is actually using AtticFoil and simply showing how it works without being part of the AtticFoil company. Cause all videos of AtticFoil are by AtticFoil, which are cool videos and all, I use AtticFoil myself, it's just more telling when someone other than the company themselves is talking about the product.
The only thing I haven't seen in all these videos is the before and after actual attic temp. Here in south Texas, next to the border, outside 100 degree F weather, my attic temp was 138 on average with insulation on the roof. I added a fan to the attic window to blow air in and goes out the top, and now the highest temp the attic gets is 112 F. Would this help at all.....
since you were making the video short you should of edited this video with an extra 20 seconds of showing the ceiling through the flir camera to show how much it really worked in its entirety. maybe even take a temperature of the room before attic foil and how cool it is after installing attic foil.
@Archifx Accolades to you for using a Thermal Imaging Camera to PRECISELY measure temperatures. Good Choice!! Thermal Imaging cameras like the one you used are typically accurate down to a 1/2 inch from 60 ft. away, as opposed to Infrared Temperature Guns used (and criticized) in most insulation videos which are far less accurate and only give the AVERAGE temperature of a much larger area. Several videos very convincingly explain that the air gap is critical to optimal results with radiant barrier insulation. That was my first concern upon seeing that the product wasn't attached to the underside of the rafters. However, @1:00 the piece of tape is creating a baffle effect which leaves no question that air gap IS present. For me personally, thank you for the providing the final word on the answer to a question that I've been asking FOR YEARS . . . which was: Why all the emphasis on ceiling insulation? Why let all that heat in, in the first place? Why isnt the roof insulated instead? It never made sense to me. I've asked numerous carpenters and others I know in the construction trades. No one had an answer. Researching on my own via Google, the only takeaway was Not to Create a Moisture Trap / Mold Issue. That, I understood, and didn't really pursue it any further even though I still felt my logic made a lot of sense. Fastforward to radiant barriers . . . YAY!! If the air gap, possibly soffet vents, and IMO, ideally a ridge vent (possibly essential?) eliminate the moisture risk, that's it then, Right?!? No more hot attics.
yes, but is it specifically the radiant barrier from the "AtticFoil" company or are you just using the kind you get at hardware stores?? Cause from what I hear is that there really is a big difference in using the "AtticFoil" brand vs whatever brand is sold at hardware stores.
I have a question or an idea for your next video. Take a thick mil plastic or the type you put in flowers beds and see how good it will do against your radiant barrier. Tack it to the outside of the rafters and let the hot air flow to the roof vents. Several of us have been talking about this but have not gotten around to trying it yet.
Need to see how the attic temp changes at a set height on similar ambient conditions days without and with the RB. I had most of my attic sheathing being Tech Shield with the aluminum coating but they ran out of that sheathing and put up regular OSB in one area. The temp this summer was pretty hot and I saw a 20-30 degrees temp difference between the regular OSB and the Tech Shield. So I put up the attic foil in the areas that just had regular OSB. I have not seen any substantial reduction in the temperature inside the attic. I stretched my attic foil across the rafters and not pushed up inside each rafter bay but that’s they way most have advocated doing it. I’m guessing there’s more radiant heat bouncing around and staying in the attic than it all being reflected back out through the roof. I’ll work next on better passive air flow with more ridge vent but not sure of the benefit there as well.
What brand of RB are you using? You should be seeing at least a 10 degree drop even without ventilation since the radiant heat isn't penetrating through the roof. Do you have every wall and entire roof covered?
You can see the air gap in the video. It looks like he has a 1/2" inch strip of rigid insulation running down the center of the joist cavity to maintain the air gap.
So that meant the shingles on ur roof are hotter cause the heat is reflected back to the roof and any roofer will tell u the hotter the roof the faster u shingles get destroyed.
It looks like it made the roof sheeting much hotter. I wonder how much that affects shingle life and if it affects shingle warranties? Another question I have is does it increase or decrease heating costs in the winter?
Good to see the difference of temperature but why barrier from inside? Why not RB is installed externally to radiate back heat energy?.Will it affect sheathing, underlayment and shingles at roofing?
No. That’s where the venting is so important. If the ridge is properly vented with a ridge vent or a perfectly set up gable vent system or in my case a power ventilator, the heat is removed as soon as it comes it. Think “redirection”
I question, not that Radiant barrier isn't working but does it work less well than hanging corrugated cardboard over rafters? Ever buy a coffee and they hand it over with a cardboard sleeve. The heat doesn't transfer through. I wonder if you have similar to better results moving the heated air up to the attic air / roof vents with less expensive material.
You need a material with low emissivity to make a good radiant barrier. Cardboard makes a decently cheap insulator, hence why they use it on coffee, but it will radiate it's heat out into whatever space it's in as it has a high surface emissivity. Foil makes a good barrier because it is both light and has extremely low emissivity. This means that it cannot hold very much total heat (because it is low mass) and it doesn't radiate what little heat it absorbs because it has very low surface emissivity. By contrast, cardboard hanging in the attic will absorb and store heat and release it back into the attic space over time as a function of it's higher mass, higher specific heat capacity, and higher surface emissivity. Cardboard would function better as an insulation layer between the hot attic space and the sheetrock I think, but there are much better materials that are made for that purpose and much more flame retardant.
A thermal camera cannot accurately measure the temperature of high reflectivity/low emmisivity surfaces, because only emmitted radiation provides information about the objects temperature. The camera is calibrated for high emmisivity surfaces roughly 0.95, it cannot tell you the temperature of the foil. However the laws of thermodynamics telm us that the foil wil be in equilibrium with the rest of the roof and just as hot. You are measuring this completely wrong and misleading people.
@WE_not_Me @1:00 Noice the baffle effect created by the piece of tape that's temporarily securing the end of the foil. IF there was NO SPACE between the sheathing and the attic foil, you wouldn't see that (baffle effect).
THIS. is what i want to know. spray foam installation is too risky. installer gets the mixture wrong or doesnt let the first layer cure and your house will smell like salmon for a decade.
@@Archifxthank you for your reply. i’m going to buy a roll of this. i was going to staple this to the rafters. did you add additional blowin insulation after installing the RB? any improvements on your electric bill? thank you
I have spray foam, It definitely delivers on insulation claims, and comfort. The windows and doors are tight as well. I can't exaggerate how well it works. Roof leaks are fun. Found a boot rotten on a plumbing vent, roughly in line with where the leak showed up. I do like the part where it can be over 100f with 80%rh, and the attic is 85f. I'm sure radiant barrier can work with other insulation strategies to achieve equal results. Bang for the buck, spray foaming roof deck is hard to beat. It's been in for 13 years and shows no sign of degradation or loss in performance. Energy bills down from 750 to 200 with perfect comfort control in any weather. 100f outside and miserably high humidity, inside it's 70f and 55%rh.
Are you aware that you installed that incorrectly? You need an air gap. Needs to be stapled to the rafters not the roofing board or you create thermal bridging.
I installed Attic Foil a year or so ago and am very satisfied with the results. Every home should have this.
I find a lot of videos of people putting up a radiant barrier but none of them are actually mentioning which radiant barrier they are using and from the looks of it, all videos looks like they are using something thats NOT from AtticFoil. Your the first independent person that is actually using AtticFoil and simply showing how it works without being part of the AtticFoil company. Cause all videos of AtticFoil are by AtticFoil, which are cool videos and all, I use AtticFoil myself, it's just more telling when someone other than the company themselves is talking about the product.
Great video. Thank you! I would bet that the performance would be even greater if you left an air gap.
There is an air gap… 1”
This is exactly the information I was looking for! Thank you so much! 👍
The only thing I haven't seen in all these videos is the before and after actual attic temp.
Here in south Texas, next to the border, outside 100 degree F weather, my attic temp was 138 on average with insulation on the roof.
I added a fan to the attic window to blow air in and goes out the top, and now the highest temp the attic gets is 112 F. Would this help at all.....
since you were making the video short you should of edited this video with an extra 20 seconds of showing the ceiling through the flir camera to show how much it really worked in its entirety. maybe even take a temperature of the room before attic foil and how cool it is after installing attic foil.
@Archifx Accolades to you for using a Thermal Imaging Camera to PRECISELY measure temperatures. Good Choice!!
Thermal Imaging cameras like the one you used are typically accurate down to a 1/2 inch from 60 ft. away, as opposed to Infrared Temperature Guns used (and criticized) in most insulation videos which are far less accurate and only give the AVERAGE temperature of a much larger area.
Several videos very convincingly explain that the air gap is critical to optimal results with radiant barrier insulation. That was my first concern upon seeing that the product wasn't attached to the underside of the rafters.
However, @1:00 the piece of tape is creating a baffle effect which leaves no question that air gap IS present.
For me personally, thank you for the providing the final word on the answer to a question that I've been asking FOR YEARS . . . which was:
Why all the emphasis on ceiling insulation?
Why let all that heat in, in the first place? Why isnt the roof insulated instead?
It never made sense to me. I've asked numerous carpenters and others I know in the construction trades. No one had an answer.
Researching on my own via Google, the only takeaway was Not to Create a Moisture Trap / Mold Issue. That, I understood, and didn't really pursue it any further even though I still felt my logic made a lot of sense.
Fastforward to radiant barriers . . . YAY!!
If the air gap, possibly soffet vents, and IMO, ideally a ridge vent (possibly essential?) eliminate the moisture risk, that's it then, Right?!? No more hot attics.
Same Here, i bought a Large roll and installed in new patio, our attic temps dropped a bunch, our typical summer day is 105-110 most of the day.
Yeah. It’s incredible
I know this video is meant to prove temp changes with RBI but you should have mentioned to never install
rbi without gap to promote air flow
I said that 30 times on my video and channel
@@Archifx tag it? I don't watch your channel so can't comment on that.
How To Install Radiant Barrier in a Cathedral Vaulted Ceiling Roof | Attic Foil
ruclips.net/video/kYejFktgyo4/видео.html
We use radiant barrier often. It’s good stuff!
yes, but is it specifically the radiant barrier from the "AtticFoil" company or are you just using the kind you get at hardware stores?? Cause from what I hear is that there really is a big difference in using the "AtticFoil" brand vs whatever brand is sold at hardware stores.
I have a question or an idea for your next video. Take a thick mil plastic or the type you put in flowers beds and see how good it will do against your radiant barrier. Tack it to the outside of the rafters and let the hot air flow to the roof vents. Several of us have been talking about this but have not gotten around to trying it yet.
Need to see how the attic temp changes at a set height on similar ambient conditions days without and with the RB. I had most of my attic sheathing being Tech Shield with the aluminum coating but they ran out of that sheathing and put up regular OSB in one area. The temp this summer was pretty hot and I saw a 20-30 degrees temp difference between the regular OSB and the Tech Shield. So I put up the attic foil in the areas that just had regular OSB. I have not seen any substantial reduction in the temperature inside the attic. I stretched my attic foil across the rafters and not pushed up inside each rafter bay but that’s they way most have advocated doing it. I’m guessing there’s more radiant heat bouncing around and staying in the attic than it all being reflected back out through the roof.
I’ll work next on better passive air flow with more ridge vent but not sure of the benefit there as well.
What brand of RB are you using? You should be seeing at least a 10 degree drop even without ventilation since the radiant heat isn't penetrating through the roof. Do you have every wall and entire roof covered?
Was the attic foil installed with an air gap between it and the decking? If not, would love to see a comparison of those two.
You can see the air gap in the video. It looks like he has a 1/2" inch strip of rigid insulation running down the center of the joist cavity to maintain the air gap.
So that meant the shingles on ur roof are hotter cause the heat is reflected back to the roof and any roofer will tell u the hotter the roof the faster u shingles get destroyed.
It looks like it made the roof sheeting much hotter. I wonder how much that affects shingle life and if it affects shingle warranties?
Another question I have is does it increase or decrease heating costs in the winter?
Good to see the difference of temperature but why barrier from inside? Why not RB is installed externally to radiate back heat energy?.Will it affect sheathing, underlayment and shingles at roofing?
No. That’s where the venting is so important. If the ridge is properly vented with a ridge vent or a perfectly set up gable vent system or in my case a power ventilator, the heat is removed as soon as it comes it. Think “redirection”
RB is not made to withstand exterior elements. They are durable for indoor applications only. That's why it's not installed facing out.
Correct. They sell a product : roofingfoil.com to achieve this but I do not know how well it works.
If you could write RB manufacturer name in the description or link of Amazon. Thanks
Remarkable !
Can you then put fiberglass insulation against your barrier and then osb board if you wanted a finished attic?
I question, not that Radiant barrier isn't working but does it work less well than hanging corrugated cardboard over rafters? Ever buy a coffee and they hand it over with a cardboard sleeve. The heat doesn't transfer through. I wonder if you have similar to better results moving the heated air up to the attic air / roof vents with less expensive material.
The question would be the longevity of that product. I understand your theory
You need a material with low emissivity to make a good radiant barrier. Cardboard makes a decently cheap insulator, hence why they use it on coffee, but it will radiate it's heat out into whatever space it's in as it has a high surface emissivity. Foil makes a good barrier because it is both light and has extremely low emissivity. This means that it cannot hold very much total heat (because it is low mass) and it doesn't radiate what little heat it absorbs because it has very low surface emissivity. By contrast, cardboard hanging in the attic will absorb and store heat and release it back into the attic space over time as a function of it's higher mass, higher specific heat capacity, and higher surface emissivity. Cardboard would function better as an insulation layer between the hot attic space and the sheetrock I think, but there are much better materials that are made for that purpose and much more flame retardant.
Measuring radiation temperature ... doesnt mean they have different temperatures.
What about in winter
A thermal camera cannot accurately measure the temperature of high reflectivity/low emmisivity surfaces, because only emmitted radiation provides information about the objects temperature.
The camera is calibrated for high emmisivity surfaces roughly 0.95, it cannot tell you the temperature of the foil. However the laws of thermodynamics telm us that the foil wil be in equilibrium with the rest of the roof and just as hot.
You are measuring this completely wrong and misleading people.
Exactly right.
Attic sheathing doesn't look like OSB, may be plywood?
In this case I used plywood yes. Same purpose, same thermal attributes
Why is there no gap between the foil and the roof? It doesn't work without a gap between the foil and the wood.
You must not have paid attention
@WE_not_Me @1:00 Noice the baffle effect created by the piece of tape that's temporarily securing the end of the foil.
IF there was NO SPACE between the sheathing and the attic foil, you wouldn't see that (baffle effect).
you're supposed to have an air gap, not installed directly against the roof sheething
Apparently you didn’t see the video where I illustrate a 1” air gap.
Sold
Is this radiant foil better than spray-on foam insulation?
THIS. is what i want to know. spray foam installation is too risky. installer gets the mixture wrong or doesnt let the first layer cure and your house will smell like salmon for a decade.
@Mark-wr1hz I’ve lived it. Stick to the fiberglass or cellulose. If there’s an error it’s fixable. Don’t make your home a science experiment
Anything is better than spray foam cancerulation
@@Archifxthank you for your reply. i’m going to buy a roll of this. i was going to staple this to the rafters. did you add additional blowin insulation after installing the RB? any improvements on your electric bill? thank you
I have spray foam, It definitely delivers on insulation claims, and comfort. The windows and doors are tight as well. I can't exaggerate how well it works.
Roof leaks are fun. Found a boot rotten on a plumbing vent, roughly in line with where the leak showed up.
I do like the part where it can be over 100f with 80%rh, and the attic is 85f. I'm sure radiant barrier can work with other insulation strategies to achieve equal results. Bang for the buck, spray foaming roof deck is hard to beat. It's been in for 13 years and shows no sign of degradation or loss in performance. Energy bills down from 750 to 200 with perfect comfort control in any weather. 100f outside and miserably high humidity, inside it's 70f and 55%rh.
Are you aware that you installed that incorrectly? You need an air gap. Needs to be stapled to the rafters not the roofing board or you create thermal bridging.
1” is all you need my friend. Foam creates the thermal break. The room is ice cold west facing in the summer in FL. I did it right but good try.
@@Archifx that's what she said! re: 1" is all you need. Yes as long as there is an air gap of any size.
You’re doing it wrong if she has time to even say it