We are excited and have an appointment scheduled in a couple weeks! All of your videos and informative information is what totally sealed the deal for us to choose Insulwise. We’ve only had our cape cod home for a year and noticed our current insulation isn’t doing the job. I’m very eager to see the results!
Hi there, thanks for the kind comment! We do everything we can to help homeowners understand why their homes are not as comfortable or energy efficient as they'd like them to be, and then show our unique and effective ways of remedying those issues. We look forward to seeing you in a few weeks!
I have a cape cod home with soffits and a ridge vent. At the sloped ceiling, i tried to shove baffles up there but couldn't bc of all the nails everywhere. So i currently have 6ft strips that are about 3 inches wide in every other bay. The slope is almost 8 ft long. Is my attempt worthless and take them out? With the old insulation that is currently in the sloped ceiling and nailed down by the roof shingle nails, there is minimal or not any air flow from the soffit to the ridge. Do i need vents at the top of my knee wall/close to the bottom of my ceiling slope. Or will the exhaust vent cancel out my ridge vent. I am also planning on getting a new roof in the next yr or 2. Add exhaust vents at the kneewall area or have both ridge vent and exhaust vents or just exhaust vents at the top of the roof?
Hi there, yes Capes can be confusing, especially to ventilate. If you've air sealed the knee wall spaces properly, and your soffit vents are venting well, that should be sufficient to take care of those spaces. I wouldn't worry about trying to do intake and exhaust for your smaller attic spaces. For your slope ceilings, I give you credit for even attempting to baffle them, that's a heckuva a chore! If it were me I would not have tried to get the baffles into place, but instead used that minimal roof rafter space for additional R-Value with a blown insulation. You do need to make sure that if you're sloped bays are not baffled, that they are well air sealed. Any light fixtures, switches, recessed lights in your slope ceiling bays need to be air sealed to prevent moisture from getting into those bays by Stack Effect driven air leakage from your home. When you get the new roof you could have them add an undershingle vent across the knee wall space for additional ventilation if you wanted to. When these spaces are well air sealed, and there are vents installed, I have never seen one develop a mold problem, so you should be good. Andy
Amazing video!! We currently live in a 1958 Cape Cod home with very old batting insulation within that knee wall scrawl space that are stapled to the roof rafter areas--of which most of them are falling down and not working properly which is why are are looking to update it (pictures in the below links) What would your approach be if a Cape Cod does not have soffit vents? We do have ridge vents at the peak of the roof and gable vents up in the peak area as well. We have had 2 different energy companies come out to our house and give us their opinions on what to do and it was typically a combination of: - Spray foam the corner of the house (where the soffits typically would be) up until it reaches the knee wall/slope area before it goes into the actual sloped area - Spray in packed cellulose in the sloped area - Spray in cellulose in the Devil's triangle peak area. - Combining all of this with some foil/foam stuff to seal in the cellulose. - A graphic of this is highlighted in the "Company's Plan" link below Both companies said by doing this we wouldn’t need to insulate the lower flat attic since this would now be a “conditioned” space nor would we have to spray foam any of the air gaps from let's say canned lights, etc. I kind of see the logic here, but I feel you would want to also seal off any air gaps between the 1st and the 2nd floor since we already have return vents upstairs in our HVAC system. They also said that since this would now be conditioned space, the area of the attic wouldn't be too much hotter than our actual bedroom on the other side of the knee wall--which I find hard to believe.... Secondly-I always thought that the attic needed ventilation but according to these two companies, they said we didn’t need ventilation since they would be making it a conditioned space. If we were to completely seal that attic space, that means no air would be going through the slope area and out of the ridge vent-which I thought was the reason for having such things. With this setup, I am worried about moisture build-up, mold, and reducing the life of our roof. Additionally--I am not so sure about the spray foam since from what I read contains a bunch of toxic materials, and we can't even be in the house from 24-72 hours after they spray it in, which is concerning since it is unknown what the long-term effects from this may be after breathing it in constantly. The companies said they don't recommend batting insulation anymore for the areas that touch the roof hence why they switched to spray foam..... Looking for any professional guidance on this project--trying to be the most effective since the summers in this house are unbearably hot. Thanks so much for any help! idge vent-which I thought was the reason for having such things. With this setup, I am worried about moisture build-up, mold, and reducing the life of our roof. Additionally--I am not so sure about the spray foam since from what I read contains a bunch of toxic materials, and we can't even be in the house from 24-72 hours after they spray it in, which is concerning since it is unknown what the long-term effects from this may be after breathing it in constantly. The companies said they don't recommend batting insulation anymore for the areas that touch the roof hence why they switched to spray foam..... Apologies for the long comment--Looking for any professional guidance on this project--trying to be the most effective since the summers in this house are unbearably hot. Thanks so much for any help! Wish you guys serviced Northern Virginia/DC area.... Links to pics below: Insulation Pic 1 - imgur.com/a/vrfyJHv Insulation Pic 2 - imgur.com/a/GFaDcS7 Insulation Pic 3 - imgur.com/a/j0i4evM Insulation Pic 4 - imgur.com/a/vGZdE1E Company's plan - imgur.com/a/KrqS5xs
Thanks! I took a look at the pics and you have a pretty standard Cape design home. I'd say their overall approach is good, with one caveat I explain below. If they spray foam the underside of the roof in the knee wall spaces as well as the exposed gable end walls inside the space that will make those spaces "conditioned spaces." That will eliminate the need to do any air sealing in those spaces. If they then dense pack the slope bays and air seal / insulate the upper attic space that should produce a good solution (it sounds like you have good ventilation in the upper attic). The only question I'd have is what type of spray foam do they want to use on the underside of the roof? In my opinion and the opinion of many others in the building science community, the ONLY type of foam that should ever be used for insulating the underside of roofs is closed cell foam. This is because closed cell foam at 2" thickness creates a vapor barrier. Most companies use open cell foam because it's faster/ cheaper/ easier and the homeowners usually aren't aware there's a difference. However -- open cell foam does NOT have a vapor barrier. And water vapor can migrate through it, get trapped against the shingles and rot the roof. I have worked on jobs where this has happened and have dealt with the after effects. It is not a myth. Closed cell foam is more expensive, but I would not want to play with my roof. We don't use closed cell foam in these situations because it's prohibitively expensive and I simply don't like the idea of a roof having a coating on the underside of it if it can be avoided. At least 25% of the attics we work in have a small roof leak somewhere that the homeowner was unaware of. A well ventilated attic will tolerate small minor roof leaks (it sounds crazy but we see it all the time). Heck I have a video showing an example of this. If you have foam sprayed onto the roof there's a solid chance you're not going to know you've got a leak until you've got a real problem (happened on the project that I worked on). If they use open cell foam you may never have a problem (at least not that you'll be aware of for several years). It is just not what's recommended. I'd recommend having them quote you for closed cell foam on the underside of the roof. But first DO your research on this...google closed cell versus open cell foam when applied to roofs and you'll learn all that you need to. You may also learn that you want a different contractor in the process (but hopefully not). Hope this helps! Andy
@@insulwiseenergycomfortsolu3293 thanks so much for your thoughtful reply!! Super helpful. One quick follow-on question to this-we were thinking of not doing the spray foam, so out of the contractors plans-what would you suggest they do if they don’t do the spray foam, but something else? Do what you did in this project in the video where you leave that roof line untouched and then just do batting on the knee wall and the cellulose spray foam in the bottom? We would like to keep our crawl space semi-workable for storage so the cellulose spray in on the bottom were on the fence about… Thanks Andy!
@@agacom1 You're welcome! If they did the same thing in your Cape that I do in this video you'll have a fine result. Batting the knee walls with R-19 fiberglass and covering them with a building wrap is the easy part. The other critical things are sealing the voids underneath the knee walls, air sealing the outlets in the knee walls with foam / caulk, and air sealing all of the air leaks in the floor of the knee walls before insulating with cellulose. Lastly, if your knee wall spaces are not vented via soffit or under shingle vents, they should be vented using something like the slant back vents that you see me use in the video. You never want to have an insulated, unconditioned space that is unventilated. It becomes a perfect situation for mold growth. Hope this helps! Andy
@@insulwiseenergycomfortsolu3293 this is perfect. Thanks so so much Andy--learned more from you than I have other contractors physically coming to my house! Keep up the great channel!
You're welcome! Yes, baffles are a tough deal with these (unless the inside sloped drywall section is removed or the roof area). We've done well over a thousand homes this way and it's a standard weatherization practice in our area. The biggest thing is having the lower knee wall attics AND upper main attic effectively ventilated.
Very informative video. When you put the foam board in between the studs, does the foil backing need to be facing outwards? I have a wall along side an enclosed staircase that always feels hot. It only has batt insulation between the studs in the attic. Thank you
In the video it doesn't matter which side the foil is on. We were using the foam board to block transition gaps beneath the knee walls and it was buried in cellulose insulation later. But-- if the foam board were to be exposed -- you would want the foil side to face outward. The foil covering will act as a radiant barrier, reflecting attic heat back toward the roof and away from the home. So I believe in your application you would want it facing outward. Hope this helps! Andy
For the best result you'd want to leave the batts in place in between the stud bays of the knee wall, and then go over top of the studs with foam board. You never want to have air gaps between the insulation and the surface that you're trying to insulate, this can allow for convection currents to occur. Andy
How do you guys blow the insulation in the ceiling area of that space? Do you cut an access door into it? Or do you feed the blower into the gaps and just let it fill up?
In this case the upper attic area was large enough that we were able to cut a hole in the ceiling and enter that way. We then patched the ceiling afterward. Sometimes these upper ceilings are just too small though. If they are less than 6ft across than we will usually have to blow the upper attics by tubing up through the slopes and blowing those areas that way. It always depends on how much room we have. Thanks!
@@insulwiseenergycomfortsolu3293 Thanks for the reply! I have this situation and was wondering what the best course of action would be. May need to snake a camera up there to do an inspection before I cut a hole. I have a dormer as well that connects to that area and it would be best to have access to it.
You've got me doing an inventory of all my insulation deficiencies. Good job! :) First, how do you insulate the top and sloped sections if the top is too small to get in? My interior flat ceiling is only 5 feet between the slopes which I guesstimate makes the attic space only 3-4 feet tall. There is a single inspection hatch caulked shut but it is only 11"x12". Second, the living and dining rooms have plaster coved ceilings. I'm not sure how those were constructed but if I crawled to the outside walls in the attic above those rooms would I find a void going down behind those coves? If so, how would you seal those off?
Thanks for watching our video! To address your questions 1) We blow in the upper attic and slopes from inside the knee wall spaces by fill tubing up the slope bays if the upper attic is inaccessible. It's not fun, but it's the only way to do it. You just have to be careful not to blow any vents full...so you can't dense pack the upper attic, just loose fill it and it'll settle down from the upper ridge vent (if there is one). This process requires some real "touch" and would be easy to "screw up" for an inexperienced installer, just a heads up. 2) You'll need to inspect those "eave" areas to see what's happening there. Respirator, head lamp, knee pads, gloves. You may find there are no top plates on your exterior walls. These wall bays can then be dense packed with cellulose from above. If you have soffits or soffit vents, either install baffles to maintain an air channel into the knee wall attic (super important for preventing mold), or block the soffit openings IF they are not vented using loose tufts of fiberglass insulation (easiest way). Either way you do not want to blow your soffits / overhangs full with insulation. Let me know if this doesn't answer your question. Andy
@@insulwiseenergycomfortsolu3293 Thanks so much Andy! That's very helpful. House has no real soffits (about 6 inch stucco overhang at eaves) nor soffit vents. However, additional venting has been added on lower and upper roof. I have calculated the vent area/ attic area ratio at 1/124 (63% intake, 37% exhaust) so I believe there is adequate venting. Currently no mold or moisture issues inside the attics but there is ice damming (which I believe is due to non-existent air sealing). What is the benefit of keeping the soffit area clear in this case? Does it just ensure the roof stays as cold as possible?
@@j.frankparnell3087 In all attic spaces (at least that I can think of) you want to have the insulation extend to where it is situated over top of the exterior wall top plate, and that's about it. If it goes into the eave area and you have a gutter leak or some kind of other drainage issue, that insulation could act like a sponge to soak up moisture, and damage / rot any wood or other materials there. If the attic floor of the knee wall is air sealed, the transition gaps are sealed, other air leaks like outlets are also sealed, and the back side of the knee wall and the attic floor has been effectively insulated, you shouldn't have many ice dam issues. Now, in some instances there could be freeze / thaw effects that can happen (cold at night, warm during the day) melting the snow and then causing it to freeze again, but those prior mentioned remedies should stem ice dam related heat coming from the house. Especially if your knee walls have been effectively vented, as you mentioned they were. Andy
I have a similar design house in Bucks County PA and was considering eliminating the knee walls entirely and making it basically all sloped walls top to bottom with just a small space at the top where it is flat 4 feet wide for a ceiling. Is that feasible or better to keep the knee walls and insulate like you have done here? Right now it’s gutted to the studs for a full remodel.
Hmm..I've seen a few houses where that was done, but you end up having a fair bit of useless space at the bottom of the triangle. I have also seen where shelving / dressers have been built into the knee walls to better utilize the space. Those things get tricky to insulate though on the back end / knee wall attic side. The simplest way IMO is to leave it as is. If you use the methods that I've shown here you'll have good results. There's always ways to optimize it / make it better, it's just a matter of the time and money that you want to spend on the project. Good luck to you!
@@insulwiseenergycomfortsolu3293Sorry to keep asking questions but I only want to do this once. The insulation from the top of the knee wall to ceiling does or doesn’t need to have baffles installed? For ease of installation I am doing fiberglass batts, I would prefer cellulose dense pack but not able to do that myself and can’t afford to get the drywall done before insulation goes in. I have a ridge vent so not how that affects that part of the installation. Everything else you have shown in your videos helped me tremendously to tackle this myself and I thank you for that. Keep in mind I am currently gutted to the studs throughout the upstairs. For the moment I am mainly concerned with keeping the heat in the house and was going to install strapping on the ceiling to retain the insulation in the attic so it is not hanging down. Drywall is probably going to be spring time.
@@Mopjockey1234 No worries at all, I didn't realize you were down to bare studs, you have an excellent opportunity there. If there's no drywall on the slope ceiling, definitely install baffles into every rafter bay from the tops of the knee walls and about 18" inches up past the floor joists of the upper attic. You want the tops of the baffles to easily clear the insulation you'll be installing between the joists of the upper attic. We've done this a few times. Slope rafter bays will have baffles and R-19 batts. I'd then install R-38 batts between the collar ties (horizontal joists in the upper attic). The ridge vent up top will vent that attic space just fine (assuming it's been properly cut in and is actually venting...we sometimes find them either not cut in OR covered with a roofing membrane that massively impedes air flow. You'll want to check and confirm this). If you have other questions feel free to reach out. Andy
@ thank you again for the advice with this house. I checked and the ridge vent is definitely venting and also noticed that I have a gable vent on each end as well about 18x18 inches. Looks like no soffit vents, 2x6 for the roof rafters and 2x8 for the floor joists. One dormer on the front side of the house. I actually found the video of my house when it was for sale if you want to take a look at how it is built. Here is a link ua-cam.com/video/jiI2E2kmK8M/v-deo.htmlsi=ZVOne8sUBJKPnKhm
@@Mopjockey1234You're welcome! I had a quick look at the video, it's a classic and simple Cape, should be straight forward to upgrade the insulation. You'll need to insulate the sides of the dormer walls that are accessible inside the front knee wall spaces as well. You may need to cut additional access points into those knee wall spaces. Do you have a way to ventilate the knee walls? You don't have overhangs / soffit vents. What we would do is install slant back vents, like I do in the video. Andy
Some people have reported that cellulose insulation leaves their house smelling very badly for a very long time. Many months or even years after it has been installed. I wanted to ask you what your experience has been with this and if there is a specific cellulose brand that is better and doesn't smell and have this problem over another?
Good question. Cellulose insulation basically just smells like paper, as far as I can tell. We air seal all of the attic floors that we work in prior to insulating them, so there really isn't much of a smell that comes down into the home. I've used just about every brand of cellulose insulation out there and it all smells pretty much the same to me. That said -- there have been a few cases of cellulose insulation being used as a damp wall-spray application in new construction and it was not allowed to dry properly before the drywall was put over it. I've heard of that creating a bad smell, but not cellulose on it's own.
We are excited and have an appointment scheduled in a couple weeks! All of your videos and informative information is what totally sealed the deal for us to choose Insulwise. We’ve only had our cape cod home for a year and noticed our current insulation isn’t doing the job. I’m very eager to see the results!
Hi there, thanks for the kind comment! We do everything we can to help homeowners understand why their homes are not as comfortable or energy efficient as they'd like them to be, and then show our unique and effective ways of remedying those issues. We look forward to seeing you in a few weeks!
I have a cape cod home with soffits and a ridge vent. At the sloped ceiling, i tried to shove baffles up there but couldn't bc of all the nails everywhere. So i currently have 6ft strips that are about 3 inches wide in every other bay. The slope is almost 8 ft long. Is my attempt worthless and take them out? With the old insulation that is currently in the sloped ceiling and nailed down by the roof shingle nails, there is minimal or not any air flow from the soffit to the ridge.
Do i need vents at the top of my knee wall/close to the bottom of my ceiling slope. Or will the exhaust vent cancel out my ridge vent. I am also planning on getting a new roof in the next yr or 2. Add exhaust vents at the kneewall area or have both ridge vent and exhaust vents or just exhaust vents at the top of the roof?
Hi there, yes Capes can be confusing, especially to ventilate. If you've air sealed the knee wall spaces properly, and your soffit vents are venting well, that should be sufficient to take care of those spaces. I wouldn't worry about trying to do intake and exhaust for your smaller attic spaces.
For your slope ceilings, I give you credit for even attempting to baffle them, that's a heckuva a chore! If it were me I would not have tried to get the baffles into place, but instead used that minimal roof rafter space for additional R-Value with a blown insulation. You do need to make sure that if you're sloped bays are not baffled, that they are well air sealed. Any light fixtures, switches, recessed lights in your slope ceiling bays need to be air sealed to prevent moisture from getting into those bays by Stack Effect driven air leakage from your home.
When you get the new roof you could have them add an undershingle vent across the knee wall space for additional ventilation if you wanted to. When these spaces are well air sealed, and there are vents installed, I have never seen one develop a mold problem, so you should be good.
Andy
Amazing video!!
We currently live in a 1958 Cape Cod home with very old batting insulation within that knee wall scrawl space that are stapled to the roof rafter areas--of which most of them are falling down and not working properly which is why are are looking to update it (pictures in the below links)
What would your approach be if a Cape Cod does not have soffit vents? We do have ridge vents at the peak of the roof and gable vents up in the peak area as well.
We have had 2 different energy companies come out to our house and give us their opinions on what to do and it was typically a combination of:
- Spray foam the corner of the house (where the soffits typically would be) up until it reaches the knee wall/slope area before it goes into the actual sloped area
- Spray in packed cellulose in the sloped area
- Spray in cellulose in the Devil's triangle peak area.
- Combining all of this with some foil/foam stuff to seal in the cellulose.
- A graphic of this is highlighted in the "Company's Plan" link below
Both companies said by doing this we wouldn’t need to insulate the lower flat attic since this would now be a “conditioned” space nor would we have to spray foam any of the air gaps from let's say canned lights, etc. I kind of see the logic here, but I feel you would want to also seal off any air gaps between the 1st and the 2nd floor since we already have return vents upstairs in our HVAC system. They also said that since this would now be conditioned space, the area of the attic wouldn't be too much hotter than our actual bedroom on the other side of the knee wall--which I find hard to believe....
Secondly-I always thought that the attic needed ventilation but according to these two companies, they said we didn’t need ventilation since they would be making it a conditioned space. If we were to completely seal that attic space, that means no air would be going through the slope area and out of the ridge vent-which I thought was the reason for having such things. With this setup, I am worried about moisture build-up, mold, and reducing the life of our roof. Additionally--I am not so sure about the spray foam since from what I read contains a bunch of toxic materials, and we can't even be in the house from 24-72 hours after they spray it in, which is concerning since it is unknown what the long-term effects from this may be after breathing it in constantly. The companies said they don't recommend batting insulation anymore for the areas that touch the roof hence why they switched to spray foam.....
Looking for any professional guidance on this project--trying to be the most effective since the summers in this house are unbearably hot. Thanks so much for any help!
idge vent-which I thought was the reason for having such things. With this setup, I am worried about moisture build-up, mold, and reducing the life of our roof. Additionally--I am not so sure about the spray foam since from what I read contains a bunch of toxic materials, and we can't even be in the house from 24-72 hours after they spray it in, which is concerning since it is unknown what the long-term effects from this may be after breathing it in constantly. The companies said they don't recommend batting insulation anymore for the areas that touch the roof hence why they switched to spray foam.....
Apologies for the long comment--Looking for any professional guidance on this project--trying to be the most effective since the summers in this house are unbearably hot. Thanks so much for any help! Wish you guys serviced Northern Virginia/DC area....
Links to pics below:
Insulation Pic 1 - imgur.com/a/vrfyJHv
Insulation Pic 2 - imgur.com/a/GFaDcS7
Insulation Pic 3 - imgur.com/a/j0i4evM
Insulation Pic 4 - imgur.com/a/vGZdE1E
Company's plan - imgur.com/a/KrqS5xs
Thanks! I took a look at the pics and you have a pretty standard Cape design home. I'd say their overall approach is good, with one caveat I explain below. If they spray foam the underside of the roof in the knee wall spaces as well as the exposed gable end walls inside the space that will make those spaces "conditioned spaces." That will eliminate the need to do any air sealing in those spaces. If they then dense pack the slope bays and air seal / insulate the upper attic space that should produce a good solution (it sounds like you have good ventilation in the upper attic).
The only question I'd have is what type of spray foam do they want to use on the underside of the roof? In my opinion and the opinion of many others in the building science community, the ONLY type of foam that should ever be used for insulating the underside of roofs is closed cell foam. This is because closed cell foam at 2" thickness creates a vapor barrier. Most companies use open cell foam because it's faster/ cheaper/ easier and the homeowners usually aren't aware there's a difference. However -- open cell foam does NOT have a vapor barrier. And water vapor can migrate through it, get trapped against the shingles and rot the roof. I have worked on jobs where this has happened and have dealt with the after effects. It is not a myth.
Closed cell foam is more expensive, but I would not want to play with my roof. We don't use closed cell foam in these situations because it's prohibitively expensive and I simply don't like the idea of a roof having a coating on the underside of it if it can be avoided. At least 25% of the attics we work in have a small roof leak somewhere that the homeowner was unaware of. A well ventilated attic will tolerate small minor roof leaks (it sounds crazy but we see it all the time). Heck I have a video showing an example of this. If you have foam sprayed onto the roof there's a solid chance you're not going to know you've got a leak until you've got a real problem (happened on the project that I worked on).
If they use open cell foam you may never have a problem (at least not that you'll be aware of for several years). It is just not what's recommended.
I'd recommend having them quote you for closed cell foam on the underside of the roof. But first DO your research on this...google closed cell versus open cell foam when applied to roofs and you'll learn all that you need to. You may also learn that you want a different contractor in the process (but hopefully not). Hope this helps!
Andy
@@insulwiseenergycomfortsolu3293 thanks so much for your thoughtful reply!! Super helpful. One quick follow-on question to this-we were thinking of not doing the spray foam, so out of the contractors plans-what would you suggest they do if they don’t do the spray foam, but something else? Do what you did in this project in the video where you leave that roof line untouched and then just do batting on the knee wall and the cellulose spray foam in the bottom?
We would like to keep our crawl space semi-workable for storage so the cellulose spray in on the bottom were on the fence about…
Thanks Andy!
@@agacom1 You're welcome! If they did the same thing in your Cape that I do in this video you'll have a fine result. Batting the knee walls with R-19 fiberglass and covering them with a building wrap is the easy part. The other critical things are sealing the voids underneath the knee walls, air sealing the outlets in the knee walls with foam / caulk, and air sealing all of the air leaks in the floor of the knee walls before insulating with cellulose. Lastly, if your knee wall spaces are not vented via soffit or under shingle vents, they should be vented using something like the slant back vents that you see me use in the video. You never want to have an insulated, unconditioned space that is unventilated. It becomes a perfect situation for mold growth. Hope this helps!
Andy
@@insulwiseenergycomfortsolu3293 this is perfect. Thanks so so much Andy--learned more from you than I have other contractors physically coming to my house! Keep up the great channel!
really cool
Thanks!
Thank you! Unfortunately I only have 4 inch roof joists… even further why baffles won’t work…
You're welcome! Yes, baffles are a tough deal with these (unless the inside sloped drywall section is removed or the roof area). We've done well over a thousand homes this way and it's a standard weatherization practice in our area. The biggest thing is having the lower knee wall attics AND upper main attic effectively ventilated.
Very informative video. When you put the foam board in between the studs, does the foil backing need to be facing outwards? I have a wall along side an enclosed staircase that always feels hot. It only has batt insulation between the studs in the attic. Thank you
I was thinking I could pull the batt insulation , put the foam board in and put the batts back on top of it. Again, thank you!
In the video it doesn't matter which side the foil is on. We were using the foam board to block transition gaps beneath the knee walls and it was buried in cellulose insulation later. But-- if the foam board were to be exposed -- you would want the foil side to face outward. The foil covering will act as a radiant barrier, reflecting attic heat back toward the roof and away from the home. So I believe in your application you would want it facing outward. Hope this helps!
Andy
For the best result you'd want to leave the batts in place in between the stud bays of the knee wall, and then go over top of the studs with foam board. You never want to have air gaps between the insulation and the surface that you're trying to insulate, this can allow for convection currents to occur.
Andy
How do you guys blow the insulation in the ceiling area of that space? Do you cut an access door into it? Or do you feed the blower into the gaps and just let it fill up?
In this case the upper attic area was large enough that we were able to cut a hole in the ceiling and enter that way. We then patched the ceiling afterward. Sometimes these upper ceilings are just too small though. If they are less than 6ft across than we will usually have to blow the upper attics by tubing up through the slopes and blowing those areas that way. It always depends on how much room we have.
Thanks!
@@insulwiseenergycomfortsolu3293 Thanks for the reply! I have this situation and was wondering what the best course of action would be. May need to snake a camera up there to do an inspection before I cut a hole. I have a dormer as well that connects to that area and it would be best to have access to it.
You've got me doing an inventory of all my insulation deficiencies. Good job! :) First, how do you insulate the top and sloped sections if the top is too small to get in? My interior flat ceiling is only 5 feet between the slopes which I guesstimate makes the attic space only 3-4 feet tall. There is a single inspection hatch caulked shut but it is only 11"x12". Second, the living and dining rooms have plaster coved ceilings. I'm not sure how those were constructed but if I crawled to the outside walls in the attic above those rooms would I find a void going down behind those coves? If so, how would you seal those off?
Thanks for watching our video! To address your questions
1) We blow in the upper attic and slopes from inside the knee wall spaces by fill tubing up the slope bays if the upper attic is inaccessible. It's not fun, but it's the only way to do it. You just have to be careful not to blow any vents full...so you can't dense pack the upper attic, just loose fill it and it'll settle down from the upper ridge vent (if there is one). This process requires some real "touch" and would be easy to "screw up" for an inexperienced installer, just a heads up.
2) You'll need to inspect those "eave" areas to see what's happening there. Respirator, head lamp, knee pads, gloves. You may find there are no top plates on your exterior walls. These wall bays can then be dense packed with cellulose from above. If you have soffits or soffit vents, either install baffles to maintain an air channel into the knee wall attic (super important for preventing mold), or block the soffit openings IF they are not vented using loose tufts of fiberglass insulation (easiest way). Either way you do not want to blow your soffits / overhangs full with insulation.
Let me know if this doesn't answer your question.
Andy
@@insulwiseenergycomfortsolu3293 Thanks so much Andy! That's very helpful. House has no real soffits (about 6 inch stucco overhang at eaves) nor soffit vents. However, additional venting has been added on lower and upper roof. I have calculated the vent area/ attic area ratio at 1/124 (63% intake, 37% exhaust) so I believe there is adequate venting. Currently no mold or moisture issues inside the attics but there is ice damming (which I believe is due to non-existent air sealing). What is the benefit of keeping the soffit area clear in this case? Does it just ensure the roof stays as cold as possible?
@@j.frankparnell3087 In all attic spaces (at least that I can think of) you want to have the insulation extend to where it is situated over top of the exterior wall top plate, and that's about it. If it goes into the eave area and you have a gutter leak or some kind of other drainage issue, that insulation could act like a sponge to soak up moisture, and damage / rot any wood or other materials there. If the attic floor of the knee wall is air sealed, the transition gaps are sealed, other air leaks like outlets are also sealed, and the back side of the knee wall and the attic floor has been effectively insulated, you shouldn't have many ice dam issues. Now, in some instances there could be freeze / thaw effects that can happen (cold at night, warm during the day) melting the snow and then causing it to freeze again, but those prior mentioned remedies should stem ice dam related heat coming from the house. Especially if your knee walls have been effectively vented, as you mentioned they were.
Andy
@@insulwiseenergycomfortsolu3293 I hadn't thought of the gutter leak possibility. Thanks again Andy!
I have a similar design house in Bucks County PA and was considering eliminating the knee walls entirely and making it basically all sloped walls top to bottom with just a small space at the top where it is flat 4 feet wide for a ceiling. Is that feasible or better to keep the knee walls and insulate like you have done here? Right now it’s gutted to the studs for a full remodel.
Hmm..I've seen a few houses where that was done, but you end up having a fair bit of useless space at the bottom of the triangle. I have also seen where shelving / dressers have been built into the knee walls to better utilize the space. Those things get tricky to insulate though on the back end / knee wall attic side. The simplest way IMO is to leave it as is. If you use the methods that I've shown here you'll have good results. There's always ways to optimize it / make it better, it's just a matter of the time and money that you want to spend on the project. Good luck to you!
@@insulwiseenergycomfortsolu3293Sorry to keep asking questions but I only want to do this once. The insulation from the top of the knee wall to ceiling does or doesn’t need to have baffles installed? For ease of installation I am doing fiberglass batts, I would prefer cellulose dense pack but not able to do that myself and can’t afford to get the drywall done before insulation goes in. I have a ridge vent so not how that affects that part of the installation. Everything else you have shown in your videos helped me tremendously to tackle this myself and I thank you for that. Keep in mind I am currently gutted to the studs throughout the upstairs. For the moment I am mainly concerned with keeping the heat in the house and was going to install strapping on the ceiling to retain the insulation in the attic so it is not hanging down. Drywall is probably going to be spring time.
@@Mopjockey1234 No worries at all, I didn't realize you were down to bare studs, you have an excellent opportunity there. If there's no drywall on the slope ceiling, definitely install baffles into every rafter bay from the tops of the knee walls and about 18" inches up past the floor joists of the upper attic. You want the tops of the baffles to easily clear the insulation you'll be installing between the joists of the upper attic. We've done this a few times. Slope rafter bays will have baffles and R-19 batts. I'd then install R-38 batts between the collar ties (horizontal joists in the upper attic). The ridge vent up top will vent that attic space just fine (assuming it's been properly cut in and is actually venting...we sometimes find them either not cut in OR covered with a roofing membrane that massively impedes air flow. You'll want to check and confirm this).
If you have other questions feel free to reach out.
Andy
@ thank you again for the advice with this house. I checked and the ridge vent is definitely venting and also noticed that I have a gable vent on each end as well about 18x18 inches. Looks like no soffit vents, 2x6 for the roof rafters and 2x8 for the floor joists. One dormer on the front side of the house. I actually found the video of my house when it was for sale if you want to take a look at how it is built. Here is a link ua-cam.com/video/jiI2E2kmK8M/v-deo.htmlsi=ZVOne8sUBJKPnKhm
@@Mopjockey1234You're welcome! I had a quick look at the video, it's a classic and simple Cape, should be straight forward to upgrade the insulation. You'll need to insulate the sides of the dormer walls that are accessible inside the front knee wall spaces as well. You may need to cut additional access points into those knee wall spaces. Do you have a way to ventilate the knee walls? You don't have overhangs / soffit vents. What we would do is install slant back vents, like I do in the video.
Andy
Some people have reported that cellulose insulation leaves their house smelling very badly for a very long time. Many months or even years after it has been installed. I wanted to ask you what your experience has been with this and if there is a specific cellulose brand that is better and doesn't smell and have this problem over another?
Good question. Cellulose insulation basically just smells like paper, as far as I can tell. We air seal all of the attic floors that we work in prior to insulating them, so there really isn't much of a smell that comes down into the home. I've used just about every brand of cellulose insulation out there and it all smells pretty much the same to me. That said -- there have been a few cases of cellulose insulation being used as a damp wall-spray application in new construction and it was not allowed to dry properly before the drywall was put over it. I've heard of that creating a bad smell, but not cellulose on it's own.
Imagine doing all these upgrades🤔🤔🤔 and then a Tornado comes and rips all your stuff - completely apart😔
The farther North - the better.
I can't even imagine! Hopefully that hasn't happened to you!