Would you recommend insulation (fiberglass) on the underside of the roof decking(between roof rafters) and then your product, or just put up your product and fiberglass on the living quarters cielings? Our HVAC and ducting is in the attic. I live in Southern CA and moisture is not a really big issue. Thanks!
Thank you for sharing your knowledge with us. I am currently working on our home now, and I can tell the difference. Your videos have helped me out tremendously. Thank you 🙏
i just finished my attic which i started last summer and it was half done but i did notice better comfort and electric bill went down. its 90% done now, but theres some more room for low pitch area's. and im also adding a attic fan to get better ventilation
My installation was different, they covered soffet vents left no gap at bottom and left a gap at top ridge vent. Should I use a razor and cut bottom of the foil near the soffet?
Question: I noticed that I don’t have any vents up top but in the video it says to still leave a gap at the top. Would the hot air make its way to the top and exit through the soffit vent at the bottom later on? I’m confused as to where the air would escape up top? Thank you for your time.
Yes, even if your vents are lower than the ridge, you still want to leave gap at the top. Basically hot air will "pool" in the top of the attic and you want to give it a way to get out. Even if it's down a couple feet with a wind turbine, static vent etc. Air should never hit a "Dead End".
You need to have exhaust vents added to your roof. Attic venting relies on the stack effect, which is basically hot air rises and cool air comes in to replace it. If you only have soffit vents, you aren’t giving that hot air any where to go. Proper venting will have a much bigger impact than a radiant barrier will.
Yes, having exhaust vents is BEST, but some areas (hurricane areas) we call these "water injection systems" so it not required. And actually hot air does NOT rise. The science says the thinner air is "lifted" by denser air. This means that at ground level cooler/denser will lift or displace warmer/less dense air.
@@AtticFoil How does the hot air escape without exhaust vents? I’m on the coast of NC. We have hurricanes every year and I’ve never had any issues with water infiltration into exhaust vents. Most of my rentals are mobile homes too, so they’re not the best designed. I’m sure there’s some water that gets in with wind-driven rain, but it’s not frequent enough to be an issue. I’m really not trying to be argumentative. I love your product and your videos are the best videos on radiant barriers anywhere on the internet. I’m just try to make sure I’m not missing anything.
This product has NOTHING to do with controlling airflow. We WANT air to flow through the attic as though the www.AtticFoil.com is not even there. The foil is intended to REFLECT radiant heat coming off the roof and keep the insulation cooler.
Hi, I just had a shed delivered today and it has the radiant barrier on the inside of the walls. I'm happy about that but I was planning to insulate and put up drywall to make it a nicer studio space. Will it be ok to do that? Or is it better to only use drywall and no fiberglass roll insulation in between? Thanks!
It depends on whether you plan on heating/cooling the shed. If not, then no insulation. Using insulation is like building a refrigerator but not putting in a compressor. If you are going to heat/cool do this: atticfoil.com/index.php/applications/inside-exterior-walls-hotmixed-climates/
@@AtticFoil Okay, thanks! I plan on heating/cooling down the road, probably next year. If the thin silver foil barrier is already adhered to interior walls then would I leave a space between the foiled wall and the insulation? I guess my confusion is there isn't an air space between the barrier and the outside world. It is stuck on to the walls directly and it's very thin. Thank you for writing back, Whitney
For attic ventilation you want air to able to flow between the roof and the www.AtticFoil.com AND also be able to be drawn into the attic (under the foil) to help remove any moisture coming from the home. You basically want air to flow through the attic as though the radiant barrier foil is not even there.
Im in need of new roof decking and shingles but will be a few years before can afford to do that.. if i put the barrier up along the rafters would it all get trashed when the new roof goes in? Dunno if thats a usual expected thing like if have the barrior than expect to get a new one when replacing the roof...
Sorry, missed this comment. Unless they replace the roof deck www.AtticFoil.com installed in the attic will not get trashed when installing a new roof.
I just had the radiant barrier added in my hip roof attic. Which has full 12 inch soffit vent all the way around outside house and ridge vent along entire roof top. Install was quality foil radiant barrier material. Installed Exactly as it's supposed to be. Also had r 30 fiberglass added on top of r-17 existing cellulose. Also had radiant barrier layed over entire attic insulation. And after all that radiant barrier in the attic. It resulted in barely any difference in attic temp. Less than 5 degrees difference in attic temp, on same 80 degree sunny day as before radiant barrier install. While I was telling a freind of mine, how disappointed I was with the radiant barrier results in my attic. He then explained, how he had gotten the same poor results, with his radiant barrier, that he had done a couple years before mine at his house. My thermometers are digital and analog spring style and are installed mid level of the attic space. Am I checking the wrong area of the attic with thermometers? Is it common to achieve such minimul temperature results, after all this money and effort? Or does this mean somethings must have been done wrong somehow?
Yes, you are measuring the wrong thing. You are measuring air temperature not surface temperatures. This is a common question/mistake. Here is a video I did back in 2011 explaining how attic temperature is 90% based on ventilation: ua-cam.com/video/SGZevwIy8ok/v-deo.html A radiant barrier drops the surface temperature of the insulation which results in less heat flow through the insulation. Ed.
Just finished installing attic foil and left about 6-8 inch gap at the very top. I have a gable attic vent. Do you recommend running gable attic vent during peak heat in the attic or just run it when outside temp is cooler? What’s your play with radiant barrier and active attic vent?
I have a small attic space above the second story bedroom in an A frame house. The AC cant keep it comfortable during the summer. I am considering adding a mini-split but would like to try this first. There are ducts in the attic. I have not been up there to assess as there is no scuttle hole. I am not sure there will be much room for me to maneuver the foil underneath the ducts very well. Can I just drape it over everything and get some benefit? I may be able to staple in some areas and drape in others.....
Yes, if you can get a piece of www.AtticFoil.com between the hot roof and the insulation it will help. Ideally over the ductwork but below will still be ok. Don't overthink it. All you are trying to do is reduce the heat load to make the AC System be able to keep up. Basically, I if your AC can keep up on a cloudy day, then this is what you can expect after installing AtticFoil. If the home is older/leaky, I'd consider using the SuperPerf AtticFoil.
So I don’t have a gap at the bottom , so the air is forced to follow the barrier up to the ridge. Should I go through the effort to get a slit at the bottom ?
You should be fine. If in a really cold area, keep an eye on the bottom of the foil for condensation. This is caused from warm moist air leaking from the home. If so, then I'd cut some slits to help flush out the air/moisture.
Thanks for posting this -- I was about to buy dozens of cheesy attic baffle vents after seeing that my attic only has one baffle vent per sofit vent, and the idea of using the tear-resistant version of the foil is going to be so much more easier (and dualy benefit from the radiant reflection) than a baffle vent would ever be. Perfect timing for my insulation project. Question: You mentioned the contact of the insulation with the foil... is there an unacceptable amount of cellulose/fiberglass (blown-in) that the foil should not come in contact with? Anything I should look out for when prepping before blowing in more insulation after using AtticFoil to take the place of attic baffles?
Not really any "unacceptable" amount. Even if you have contact on the bottom the topside will still be acting to reflect heat. Advice? Do it this time of year!!
Thanks! I've actually just started this (among many other house projects). Appreciate your videos and science and the AtticFoil foil is superb quality!
I don't have a ridge vent and the radiant barrier install company completely covered all of the roof vents... (didn't cut holes) Is this undesirable? They claim it's fine because the air can move between the roof rafters under the barrier... They did leave space at the top and bottom... SE Michigan. Thanks!
It's not ideal, but probably not critical. You WANT air and moisture form in the attic to be able to get out the ridge vent. I'd just get a utility knife and cut a few slits about 2" wide near the top ridge vent just to be safe.
Stapling up www.AtticFoil.com will definitely help in the Summer. It's like shade or a cloudy day over your roof. As for the attic being cold? It's supposed to be cold. Vented attics are cold and keep the roof cold and dry.
I have a Spanish style house St Pete FLwith a flat roof. Do you see any issues with this? Also, the air intake for the attic is round piping located a few places around the house. I dont know where the exhaust is.
No problem at all. It will work great. We have had many customers install with similar type roofs. www.AtticFoil.com Even without exhaust vents, it will reduce radiant heat coming into the home off the roof.
@@I_discovered_civilization Normal install. You want air to flow free through and around the attic as though the www.AtticFoil.com is not even there. The Radiant Barrier is there to strictly reflect heat.
@@AtticFoil ok thanks for the non answer. Do you cover the baffles or not? It’s a simple yes you can cover them or no you should not and start above them.
You can actually use www.AtticFoil.com AS a baffle. Just cut/staple into place and then cut a slit/hole etc. a couple ft up the slope so air can enter the attic if needed.
tHanks you gave me more to think about . I only have gable vents. I'm thinking...What if I put in a collar tie so that my two gable vents were higher than the collar tie. What if I then put the foil under the collar tie . I've split the attic into two sections. hmmmm I'm still thinking.
Don't overthink it. You want air to flow freely through the attic as though the www.AtticFoil.com is not even there. Hot air will naturally end up in the top of the attic and find its way out. Whether it be a ridge vent, wind turbine or gable vent. It really does not matter if the vent is in the highest part. You don't need to "contain" or direct it. It will just flow up like water heading downhill.
@@AtticFoil tHank you! I enjoy all the videos. I think I'll deck off the roof sheathing and drape the foil. They built these houses with 3/8" plywood back in the mid 1960s
No, here is the info you are looking for including a thermal imaging video showing part of the roof with and without www.AtticFoil.com atticfoil.com/index.php/knowledge-zone/knowledge-zone-learn-about-radiant-barrier/myth-or-truth-radiant-barrier-damages-roof-shingles/
Would you recommend insulation (fiberglass) on the underside of the roof decking(between roof rafters) and then your product, or just put up your product and fiberglass on the living quarters cielings? Our HVAC and ducting is in the attic. I live in Southern CA and moisture is not a really big issue. Thanks!
You don't need insulation between the rafters on the roof. Just staple up AtticFoil and then add more insulation on the attic floor if you need it.
We bought your product after my husband watched your video. We see a noticable difference. THANK YOU!!!!
Did you use the stape up methode or did you lay it over the insulation? How mush are you savings?
Great to hear! With this hot Summer I bet you really saw a difference.
Thank you for sharing your knowledge with us. I am currently working on our home now, and I can tell the difference. Your videos have helped me out tremendously. Thank you 🙏
Thanks so much for taking the time to make this helpful post. I'll check out your site as well!
i just finished my attic which i started last summer and it was half done but i did notice better comfort and electric bill went down. its 90% done now, but theres some more room for low pitch area's. and im also adding a attic fan to get better ventilation
Was there any noticeable improvement with the attic fan?
There usually is. We have thousands of reviews here: www.shopperapproved.com/reviews/AtticFoil.com
My installation was different, they covered soffet vents left no gap at bottom and left a gap at top ridge vent. Should I use a razor and cut bottom of the foil near the soffet?
Yes, AND at the top. You want some air to be able to flow in/out of the attic area below the foil.
Thank you so, great information
Great video thanks!
Excellent video
Question: I noticed that I don’t have any vents up top but in the video it says to still leave a gap at the top. Would the hot air make its way to the top and exit through the soffit vent at the bottom later on? I’m confused as to where the air would escape up top? Thank you for your time.
Yes, even if your vents are lower than the ridge, you still want to leave gap at the top. Basically hot air will "pool" in the top of the attic and you want to give it a way to get out. Even if it's down a couple feet with a wind turbine, static vent etc. Air should never hit a "Dead End".
You need to have exhaust vents added to your roof. Attic venting relies on the stack effect, which is basically hot air rises and cool air comes in to replace it. If you only have soffit vents, you aren’t giving that hot air any where to go. Proper venting will have a much bigger impact than a radiant barrier will.
Yes, having exhaust vents is BEST, but some areas (hurricane areas) we call these "water injection systems" so it not required. And actually hot air does NOT rise. The science says the thinner air is "lifted" by denser air. This means that at ground level cooler/denser will lift or displace warmer/less dense air.
@@AtticFoil How does the hot air escape without exhaust vents? I’m on the coast of NC. We have hurricanes every year and I’ve never had any issues with water infiltration into exhaust vents. Most of my rentals are mobile homes too, so they’re not the best designed. I’m sure there’s some water that gets in with wind-driven rain, but it’s not frequent enough to be an issue.
I’m really not trying to be argumentative. I love your product and your videos are the best videos on radiant barriers anywhere on the internet. I’m just try to make sure I’m not missing anything.
Thanks for this video, really helps what we have in mind to insulate our 30yr old house with worn batts on the zinc roof
Did you ever end up installing www.AtticFoil.com ?
I would like to know the difference between installing a heavy plastic sheeting versus this vapor barrier. You do have some good points here.
This product has NOTHING to do with controlling airflow. We WANT air to flow through the attic as though the www.AtticFoil.com is not even there. The foil is intended to REFLECT radiant heat coming off the roof and keep the insulation cooler.
Hi, I just had a shed delivered today and it has the radiant barrier on the inside of the walls. I'm happy about that but I was planning to insulate and put up drywall to make it a nicer studio space. Will it be ok to do that? Or is it better to only use drywall and no fiberglass roll insulation in between? Thanks!
It depends on whether you plan on heating/cooling the shed. If not, then no insulation. Using insulation is like building a refrigerator but not putting in a compressor. If you are going to heat/cool do this: atticfoil.com/index.php/applications/inside-exterior-walls-hotmixed-climates/
@@AtticFoil Okay, thanks!
I plan on heating/cooling down the road, probably next year. If the thin silver foil barrier is already adhered to interior walls then would I leave a space between the foiled wall and the insulation? I guess my confusion is there isn't an air space between the barrier and the outside world. It is stuck on to the walls directly and it's very thin.
Thank you for writing back, Whitney
Why would you leave a gap just above the insulation if you have a roof vent at the top to pull the hot air out?
For attic ventilation you want air to able to flow between the roof and the www.AtticFoil.com AND also be able to be drawn into the attic (under the foil) to help remove any moisture coming from the home. You basically want air to flow through the attic as though the radiant barrier foil is not even there.
Im in need of new roof decking and shingles but will be a few years before can afford to do that.. if i put the barrier up along the rafters would it all get trashed when the new roof goes in? Dunno if thats a usual expected thing like if have the barrior than expect to get a new one when replacing the roof...
Sorry, missed this comment. Unless they replace the roof deck www.AtticFoil.com installed in the attic will not get trashed when installing a new roof.
I just had the radiant barrier added in my hip roof attic. Which has full 12 inch soffit vent all the way around outside house and ridge vent along entire roof top. Install was quality foil radiant barrier material. Installed Exactly as it's supposed to be. Also had r 30 fiberglass added on top of r-17 existing cellulose. Also had radiant barrier layed over entire attic insulation. And after all that radiant barrier in the attic. It resulted in barely any difference in attic temp. Less than 5 degrees difference in attic temp, on same 80 degree sunny day as before radiant barrier install. While I was telling a freind of mine, how disappointed I was with the radiant barrier results in my attic. He then explained, how he had gotten the same poor results, with his radiant barrier, that he had done a couple years before mine at his house. My thermometers are digital and analog spring style and are installed mid level of the attic space. Am I checking the wrong area of the attic with thermometers? Is it common to achieve such minimul temperature results, after all this money and effort? Or does this mean somethings must have been done wrong somehow?
Yes, you are measuring the wrong thing. You are measuring air temperature not surface temperatures. This is a common question/mistake. Here is a video I did back in 2011 explaining how attic temperature is 90% based on ventilation: ua-cam.com/video/SGZevwIy8ok/v-deo.html A radiant barrier drops the surface temperature of the insulation which results in less heat flow through the insulation. Ed.
Just finished installing attic foil and left about 6-8 inch gap at the very top. I have a gable attic vent. Do you recommend running gable attic vent during peak heat in the attic or just run it when outside temp is cooler? What’s your play with radiant barrier and active attic vent?
Set the fan ONLY to turn on if over 110 degrees in the attic. Otherwise you are just moving air and not cooling anything.
I have a small attic space above the second story bedroom in an A frame house. The AC cant keep it comfortable during the summer. I am considering adding a mini-split but would like to try this first. There are ducts in the attic. I have not been up there to assess as there is no scuttle hole. I am not sure there will be much room for me to maneuver the foil underneath the ducts very well. Can I just drape it over everything and get some benefit? I may be able to staple in some areas and drape in others.....
Yes, if you can get a piece of www.AtticFoil.com between the hot roof and the insulation it will help. Ideally over the ductwork but below will still be ok. Don't overthink it. All you are trying to do is reduce the heat load to make the AC System be able to keep up. Basically, I if your AC can keep up on a cloudy day, then this is what you can expect after installing AtticFoil. If the home is older/leaky, I'd consider using the SuperPerf AtticFoil.
So I don’t have a gap at the bottom , so the air is forced to follow the barrier up to the ridge. Should I go through the effort to get a slit at the bottom ?
You should be fine. If in a really cold area, keep an eye on the bottom of the foil for condensation. This is caused from warm moist air leaking from the home. If so, then I'd cut some slits to help flush out the air/moisture.
Thanks for posting this -- I was about to buy dozens of cheesy attic baffle vents after seeing that my attic only has one baffle vent per sofit vent, and the idea of using the tear-resistant version of the foil is going to be so much more easier (and dualy benefit from the radiant reflection) than a baffle vent would ever be. Perfect timing for my insulation project.
Question: You mentioned the contact of the insulation with the foil... is there an unacceptable amount of cellulose/fiberglass (blown-in) that the foil should not come in contact with? Anything I should look out for when prepping before blowing in more insulation after using AtticFoil to take the place of attic baffles?
Not really any "unacceptable" amount. Even if you have contact on the bottom the topside will still be acting to reflect heat. Advice? Do it this time of year!!
Thanks! I've actually just started this (among many other house projects). Appreciate your videos and science and the AtticFoil foil is superb quality!
I don't have a ridge vent and the radiant barrier install company completely covered all of the roof vents... (didn't cut holes) Is this undesirable? They claim it's fine because the air can move between the roof rafters under the barrier... They did leave space at the top and bottom... SE Michigan. Thanks!
It's not ideal, but probably not critical. You WANT air and moisture form in the attic to be able to get out the ridge vent. I'd just get a utility knife and cut a few slits about 2" wide near the top ridge vent just to be safe.
my attic is boiling in the summer, freezing in the winter, I have 10" thick batts of fiberglass plus blown in cellulose. will this help?
Stapling up www.AtticFoil.com will definitely help in the Summer. It's like shade or a cloudy day over your roof. As for the attic being cold? It's supposed to be cold. Vented attics are cold and keep the roof cold and dry.
I have a Spanish style house St Pete FLwith a flat roof. Do you see any issues with this? Also, the air intake for the attic is round piping located a few places around the house. I dont know where the exhaust is.
No problem at all. It will work great. We have had many customers install with similar type roofs. www.AtticFoil.com Even without exhaust vents, it will reduce radiant heat coming into the home off the roof.
Yeah but if there are baffles already installed? Do you cover those or do you start 3” above them?
Nothing changes. If air needs to be pulled into the attic due to pressure from a windy day, it has a path to get in.
@@AtticFoil I have baffles that come up about 3 feet. Do you cover them or start above them?
@@I_discovered_civilization Normal install. You want air to flow free through and around the attic as though the www.AtticFoil.com is not even there. The Radiant Barrier is there to strictly reflect heat.
@@AtticFoil ok thanks for the non answer. Do you cover the baffles or not? It’s a simple yes you can cover them or no you should not and start above them.
@@I_discovered_civilization Yes, cover them. Pretend they are not there and do a normal installation. Better?
At the top between trusses, can I alternate diagonally the foil pieces leaving small air gaps to stop dust and dirt from entering?
Sure.
@@AtticFoil Thanks
Can I put baffels with attic foil behind it?
You can actually use www.AtticFoil.com AS a baffle. Just cut/staple into place and then cut a slit/hole etc. a couple ft up the slope so air can enter the attic if needed.
tHanks you gave me more to think about . I only have gable vents.
I'm thinking...What if I put in a collar tie so that my two gable vents were higher than the collar tie. What if I then put the foil under the collar tie . I've split the attic into two sections. hmmmm I'm still thinking.
Don't overthink it. You want air to flow freely through the attic as though the www.AtticFoil.com is not even there. Hot air will naturally end up in the top of the attic and find its way out. Whether it be a ridge vent, wind turbine or gable vent. It really does not matter if the vent is in the highest part. You don't need to "contain" or direct it. It will just flow up like water heading downhill.
@@AtticFoil tHank you! I enjoy all the videos. I think I'll deck off the roof sheathing and drape the foil. They built these houses with 3/8" plywood back in the mid 1960s
Would it damage your shingles ??
No, here is the info you are looking for including a thermal imaging video showing part of the roof with and without www.AtticFoil.com atticfoil.com/index.php/knowledge-zone/knowledge-zone-learn-about-radiant-barrier/myth-or-truth-radiant-barrier-damages-roof-shingles/
Is it okay to have gaps between the top and bottom of rafters where the 2x4 connect to brace ?
yes