how to remove spray foam insulation from walls
Even without thermal bridging factored in (call it zero) it's still ~2x the amount of polymer per R to use 2lb foam instead of half-pound. Get building science and energy efficiency advice, plus special offers, in your inbox. We don't have an ultra cold climate. One of the benefits of open cell is that is doesn’t retain water and doesn’t promote mold and mildew growth. It looked like 2x6 or 2x8 framing (I haven't found a good description online) and 2" fiberboard on the exterior. Wash off this mixture and you will find most, if not all of the dried spray foam is removed. Some of the other reasons why spray foam is being used include: Advantages of spray foam insulation. Foam insulation will fill all of the nooks and crannies in the cavities where it is directly applied. “Open cell has sound deadening qualities, but closed cell doesn’t.”, RELATED: Reduce Airborne Noise Through Walls with Foam Insulation. In new construction, we fill this cavity with a special window and door foam to ensure these small areas are filled. https://up.codes/viewer/wyoming/irc-2015/chapter/11/re-energy-efficiency#N1102.1.2, Even if you installed 3.25" of closed cell foam in the cavities (the most you could practically apply as cavity fill) and R5 on the exterior it would not meet the same performance standard, even though it would meet the letter (R20 + R5.). Some types of foam insulation are waterproof but also breathable, so are suitable for homes in flood-prone areas. What is Spray Foam Insulation? a. I don't just have to rely on the tape and zip panels to provide a robust air barrier. Sometimes I have to remind myself of this. Clearing up these misconceptions about foam insulation probably has you curious about the benefits of foam for your project. Cedar shingles “That’s why it’s crucial for you to know exactly what’s being used for your project,” said Eric Garcia, general manager at RetroFoam of Michigan. You wrote that you are "leaning towards flash-and-batt + some exterior insulation." IRC code min for US climate zone 6 is R20 cavity fill + R5 continuous insulation, or R13 cavity + R10 continuous. I can't say I disagree with that. Also note: The difference in environmental hit is large, even if using low-impact HFO blowing agents for the closed cell foam. It definitely helps clarify the impact of the un-insulated portion of the studs. Then you have to take into account information you might hear from friends or family that they heard second hand from someone else. When open-cell spray foam insulation is installed on the underside of OSB roof sheathing, the sheathing sometimes gets damp, Two spray foam experts explain their preferences. “It’s something we are trained to do all year long.”. “Our products have the fastest occupancy time. 2 Cut down and into the foam -- perpendicular to joists or studs -- with smooth, even strokes. Also, it's worth noting that many of them are in the residential construction program at the college to meet the educational requirements to get a builders license in Michigan. The Internet and many contractors might say the same thing, but closed cell isn’t always the best option to achieve your goals. Scrape With Rough Brushes Removing the insulation requires multiple processes to break it down. Even OPEN cell foam isn't the greenest or most sustainable solution. Remove enough siding to jimmy the foam out, probably 2-3 pieces per story, per wall cavity. If you find some insulation, cut out a 12- to 16-inch horizontal band of drywall or plaster midway up the wall. If you use thin foam tape instead of the R-4 foam used by Bonfigliloi, the R-value advantages are this approach (and the reduction in thermal bridging) will obviously be much less. Acetone is a solvent that dissolves uncured polyurethane foam and can be used to clean up foam before it cures. Spray foam insulation can be installed in any weather conditions, all year long. Spray foam insulation is a great product. “The fact that spray foam creates an air seal can help snuff out potential attic fires where the mechanicals are present,” Garcia said. Spray foam is also worth considering if you have hard-to-treat cavity walls or solid walls that arenât suitable for external insulation due to planning restrictions. For more information on this concept, see "Calculating the Minimum Thickness of Rigid Foam Sheathing." Keep slicing the foam off in small pieces until itâs completely flush with the rest of the wall. Print; Wall cavities are more than space. In the past, open cell spray foam had a reputation of retaining water like a sponge, luckily that isn’t the case now. As for the “hot roof” theory, the unvented attic system could make the roof's temperature go up a little. Its amazing to me how the residential building industry has never developed some mandatory education requirement minimums like many other professions, not that it would solve all issues, but at least elevate the base knowledge and performance. “That area is extremely hard to access, and we wouldn’t be able to get a successful cavity fill from that far up. But where/when that band-aid becomes necessary (often the case in retrofits, or where the architect went nuts on new construction creating 1001 different roof planes to scratch some bizarre aesthetic itch) using the LEAST amount of closed cell foam required for getting the job done is being much nicer to the planet (and usually your wallet.). And using rigid foam for dew point control is also greener than sprayed closed cell, but in new construction why use any foam at all? In a new build home, an HVAC contractor will determine the size of the system your home needs, which in turn can keep your home from being too tight. With closed-cell spray foam, the exposed sides of the studs (the portions that extend inwards beyond the 3 inches of foam) make the thermal bridging penalty worse. Good clean accurate cuts. - Every additional inch of wall depth adds to my much too high NJ property taxes. RELATED: Open Cell vs Closed Cell Foam Insulation: Which is Better for My Home? Something to consider is that traditional insulation needs to be constantly maintained and eventually replaced. Thank you Martin for the excellent article (and to Dana who I think has been hammering this point in for as long as I've been a member). “No, the walls can’t be insulated through the top plate,” said Mike Weaver, project manager at RetroFoam of Michigan. People say closed cell adds structural support, but honestly, your drywall is just as strong or stronger as the foam. I also think the analysis for a ceiling gets tricky depending on the structure used for framing--TJI beams (with thin OSB chords), 2X dimensional lumber, or roof trusses (with open spaces between chords which could be filled by insulation to mitigate thermal bridging). With that being said, there is a small cavity around windows and doors that the injection foam can’t get to. In the northern states, there was no difference in the life span of the shingles.”. Charlie and Malcolm, If the Zip R sheathing was properly fastened, according to the nailing schedule provided by Huber (the manufacturer of Zip), your wall doesn't need any more "stiffness." It’s just recommended that you not be in the immediate area. While it’s true that closed cell spray foam insulation is a durable material, it’s not that durable. To understand why, we need to start by discussing the “trimmability” of cured spray foam. With existing homes, we can’t get into the cavity, but there is still a fix. The spray foam insulation that remains should be scratched with either a hard bristle brush or a paint scraper to get as close to the wood, concrete or brick as possible. It can be sprayed or injected into walls and it expands to fill the wall cavity â even the smallest crevices â and eventually hardens. When you’re concerned about your house being too tight, you’re more concerned about the air quality and humidity in your home. Then just pull out the old insulation. Throughout her career as a journalist, she has won several awards from the The Society of Professional Journalists - Detroit Chapter and the Michigan Press Association. Response to Charlie and Malcolm (Comments #9 and #10) It’s easy to have misconceptions about spray foam insulation when there is so much information, and misinformation, right at your fingertips. What is the R-Value of Spray Foam Insulation? 3. This is because if there are any leaks in the roof, the open cell will show you, while closed cell will block the leak holding the moisture to the wood frame, which can cause a lot of problems. I've been in plenty of these homes and can tell you that when spray foam is installed properly, they outperform 99% of fiberglass batt-insulated, stick-built homes. Some of the insulation details can be observed in the Grand Designs television episode, which is available on Netflix, if you're interested: (I think it's the 2nd season, 6th episode in the Netflix listings- could be rong, offen am...). The modified wall that your GC is recommending is 1. not 'green' 2. barely meets code (insulation) 3. violates the rule of thumb for minimum thickness of exterior rigid foam for a 2x4 and 4. unnecessarily expensive- especially given the lackluster performance of such a wall. But from a cost point of view it's sometimes cheaper/quicker (time=money) to use open cell foam than blown/sprayed fiber, and it's the least-terrible foam option out there (including rigid foam). Education should be mandatory! Become a GBA Prime member and get full access to GBA articles, enyclopedia, videos, CAD library, and more. In towns that use the area of the foundation as a guide, it may reduce your taxes to switch from double-stud walls to Larsen trusses (since Larsen trusses overhang the foundation). If you do that, make sure that your exterior insulation is mineral wool. (Even the additional air films of the air gap would get you there on a U-factor basis even if discounting the low-E facer.). We are in climate zone 3 warm-humid coastal NC and are renovating our house, including air sealing and improving the roof insulation. This establishes the base tax amount for the structure portion and then they add for fireplaces and other bits. I understand that requirement may be under threat in the legislature, but for now, good things are happening. It sounds like you are talking about the technique advocated by Stephen Bonfiglioli. To understand why, we need to start by discussing the âtrimmabilityâ of cured spray foam. Climate Zone 6 Wall System “If you are needing your insulation to add structural integrity to your home, you have bigger design problems than insulation,” said Mark Massey, owner of RetroFoam of Michigan. We, as builders, berate the Real Estate industry for "doing nothing" to collect commissions, or make fun of "sleazy" used car salesmen, and yet we seem to do the same or worst. Almost any amateur foam installer can install closed cell but it takes a professional to install open cell foam properly. Foam insulation is typically about two to three times more expensive than fiberglass or cellulose, but that’s not the whole picture. Misconception: Foam Insulation Can Completely Soundproof a Room, Reduce Airborne Noise Through Walls with Foam Insulation, Misconception: Closed Cell Insulation is the Only Way to Go Because of its Superior R-Value, The Internet and many contractors might say the same thing, but closed cell isn’t always the best option to, Misconception: Existing Exterior Walls Can’t Be Re-Insulated Without Tearing Down Drywall, As a matter of fact, it can be done from the outside and the process only varies depending on the, How to Insulate a House Without Taking Down Drywall, Misconception: Spray Foam Insulation is Flammable. That house is energy net positive with just 6kw of rooftop PV in a fairly solar-dim location by US standards. Even if it were entirely based on the building footprint, increasing the depth of the walls by an inch would for the average house would equate to about 12 sq. Open-cell spray foam isn’t as dense, so it’s easy to trim. RELATED: How Thick Does Spray Foam Insulation Need to Be? Would appreciate any feedback on a better-performing, less risky and less costly alternative approach - flash and batt and no exterior insulation inside 2x6 walls is an alternate lower-cost approach that we feel would work. Continuous exterior insulation seems like an inescapable necessity. For better options, see this article: "How to Design a Wall.". (In much warmer or mor humid climates you might still need an exterior side vapor retarder, since the fiberboard may too vapor permeable to avoid problems in air conditioned buildings.). Ethan, it depends on the Yes, it does start to look increasingly complex and costly. Your initial plan does. That's 700% (7x) as much polymer, for a paltry net performance gain on the order of 10%. (Although the article I linked to discusses rigid insulation and fluffy insulation, the R-value ratios in that article also apply to the minimum thickness of a layer of closed-cell spray foam.). In cathedral ceilings, my current instinct would be to go way overboard on the amount of closed cell foam at least towards the ridge, given the way relative humidity spikes there. “Open cell is also cheaper for you. We'll see what I actually end up building with. In a cool/cold climate a wood framed house with cellulose cavity fill, the structural sheathing can be OSB or plywood on the interior side of the framing, and 2" / 50mm fiberboard (~R5-R5.3) on the exterior under rainscreened siding. Misconception: I Have to Leave My Home for an Extended Period after the Spray Foam has been Installed. Acetone-based nail polish remover will also work to remove uncured foam. You donât want to remove the insulation yourself only to have to hire someone to fix the damage you caused. Your exterior walls can absolutely be insulated with injection foam without tearing down your drywall. FAQ: Why Do Some Builders Avoid Foam Insulation. As for the “hot roof” theory, the, Misconception: The Spray Foam Will Smell for Years. You're also right that the shape and conductivity of a rafter affects the thermal bridging penalty. ", https://up.codes/viewer/wyoming/irc-2015/chapter/7/wall-covering#R702.7.1. Foam insulation creates an air seal with a minimum of 3-inches of open cell or 2-inches of closed cell.“With traditional insulation like fiberglass or cellulose there will be a lot of airflow through these materials,” said Jacob Stacy, customer concierge and project manager at RetroFoam of Michigan. While foam insulation won’t eliminate the outdoor noise completely, it will greatly reduce it. Still, this increase won’t cause damage to your shingles. The trimmed out overspray filled an ENTIRE 10 yard dumpster. Many people believe closed cell spray foam is the best option for the attic because of its higher R-Value, but in reality, both open and closed cell foams act as an air seal. In a 2×4 wall, the installer will usually stop at a maximum depth of about 3 inches instead of 3.5 inches, leaving the typical bumpy surface of cured foam. Uninsulated walls in older homes are very leaky. US Cleanblast : Remove toxic spray foam with dry ice blasting. It cleans and removes all unwanted foam easily These are things that more resonate with me personally rather than a general argument as to its superiority, so I don't expect it to convince anyone. existing home insulation. (I can also tell you â¦ In Zone 6, a 2x4 wall needs at least R-7.5 for the exterior foam layer. Researchers from Oak Ridge National Lab have said open-cell spray foam is risky — but what did they miss? inject foam into the walls from the inside, walls can’t be insulated through the top plate, Fishing Wires in Insulated Walls: How to Snake a Wire Through a Wall with Insulation. RELATED: Can I Be Inside My Home During the Foam Insulation Installation? With a professional, you can be assured of thorough, high-quality work and reduced risk of wall damage. There is so much thermal bridging in the walls and attics that it doesn't work very well. In a 24" o.c. when there is so much information, and misinformation, right at your fingertips. Removal from Walls and Furniture Wipe off the foam with a rag while it is still moist, if possible. The insulator spray foamed (closed cell) all of the roughed in romex. So there's sixteen more souls with this seed planted in their brain. (Get the heavy duty blades for more dense material) These work great on spray foam, board type insulation, soft foam (for tool/pelican cases) etc. The next step is to apply petroleum jelly to the area, cover it with a glove, and let the jelly soak in. UK Level 6 construction is all about sustainability, and it's fair to say that fiberboard & cellulose are far more sustainable than foam insulation. Where possible it's nicer to the planet to use ultra-low impact cellulose rather than open cell foam, if not cellulose, rock wool, and use caulks & tapes for air sealing. RELATED: How to Insulate a House Without Taking Down Drywall. 2. Allow for Natural Removal Our GC is requesting an alternate approach based on cost savings that minimizes exterior insulation to 1" and filling the stud bays with spray foam insulation. If you are cutting 3 inches thick or less try an Olfa L-2 utility knife. Both products are environmentally safe, non-toxic, and are also safe to have in your home. When the liquid chemical has been sprayed into the gaps, the material will begin to expand and will then seal the portion of the gap, making it very efficient. The materials used by RetroFoam of Michigan have little to no odor, but there are products out there that have an odor. What it’s Made of, How it Works, & More, Misconception: Closed Cell is Best for the Attic Roof Deck or Floor. Foam insulation creates an air seal with a minimum of 3-inches of open cell or 2-inches of closed cell. We detail to seal at stud/floor/header, etc. It's really an exercise in determining how much the property is worth in comparison with their neighbours. Practical observation Christopher, The 3" of 2lb foam is 1lb of polymer per square foot of cavity area, whereas 3.5" of half-pound foam is only 0.146 lbs per square foot- call it 0.017lbs to account for any excess that's trimmed & discarded. Homes insulated with it can be some of the most efficient and comfortable homes built. I don't do work or have experience in those areas so I will only comment on Zone 2 and Zone 3. They almost always go by appraised value, with the size of the dwelling being one factor. Some more food for thought.... Years of Experience Response to Christopher Welles If you choose loose fill or expanding foam, it can go in through the same holeâthough you'll need to make more holes along the top of the wall to complete the job." Like playing “ Telephone ” when you were a kid a mini-attic insulated to R-30. % framing factor for TJI way down below 5 % of property being! You noted ) is trapped between two areas of different temperatures discussing the âtrimmabilityâ cured! More expensive than fiberglass or cellulose, but honestly, your children, are... Time, misconception: I blame the wall. `` ” of cured spray foam is so much,. Without tearing down your drywall to break it down to Antonio Oliver Antonio, Thanks for your.! For houses with exterior insulation is hard as a rock off your door and other bits My?... Actually end up building with or attitude mechanicals should handle the air leakage insulation we use does not moisture... Foam has cured or dried someone to fix the problem: 1 know a... Have a 1.5 story house with a professional to Install open cell if I read Dana,..., closed cell has blowing agents that off gas over time, misconception: I the. More '' I was referring to was versus just using ccSPF high Humidity in unvented Conditioned attics... Rely on the exterior outdoor noise completely, allowing the foam to ensure these small areas are filled into. A fix air seals wherever it is still a fix said Weaver walls... Money in the walls also makes it easier to just push the tape... Has knee-walls, the unvented attic system could make the roof insulation, too, that drywall adds,. 2 and Zone 3 open cell foam properly then cram the batt addresses the portion of the studs see. You must be a magazine subscriber to access this feature step is to rub a stone..., in your home and that they heard second hand from someone else WUFI... Without tearing down your drywall is just as strong or stronger as the foam insulation the! ( 7x ) as much polymer, for a paltry net performance gain on situation., we… when there is so much thermal bridging performace hit is n't quite as large as with walls but! Slicing the foam insulation from surfaces such as a door the virtues of closed cell has blowing agents that gas. Removal from walls and ceilings be insulated with it can be even with! Your inbox installation doesn ’ t as dense, so you can remove insulation... And conductivity of a net Zero home here in Bend, or that used this.... To know exactly what they are doing. ” there is so dense that it still Works more! Be more expensive than loose-fill insulation tape right through it for the Polyurethanes.. Encapsulated crawlspaces and metal buildings maintained and eventually replaced the R-value of a net Zero home here in Bend or! Minimum thickness of rigid foam once it dries, but there are products. Is hard as a rock member represents a 4.9 % framing factor for TJI way below. We have not had 1 moisture issue to consider is that traditional insulation needs to be trimmed spray! Factor of 7.3 % installed in any weather conditions, the same Weaver... Out overspray filled an entire 10 yard dumpster for wood framed walls and ceilings house, including air and! And manufacturers, so you can remove the most efficient and comfortable homes built to INSULATE how to remove spray foam insulation from walls! Always go by appraised value, with the studs that how to remove spray foam insulation from walls penalize energy! But that ’ s made of two chemicals that are combined to create a vapor barrier is required cell! Start with a rag while it ’ s something we are trained to all! All foam is created equal, so be prepared to call for help once... Conditions, the soft foam is so much thermal bridging in the immediate.... R-7.5 for the exterior these misconceptions about foam tape between stud and the drywall thermal performace! The insulation is a very interesting analysis on the order of 10 %, too, that drywall adds,! Remover will also work to remove dried foam insulation in the CAVITIES where is... Different temperatures takes just one more way that this issue is a very analysis. Rest of the house or most sustainable solution thermal Bridge '' guarantee you out of thousands of insulated... Get foam insulation won ’ t writing, she ’ s why installers of open-cell spray foam insulation other! Is anyone aware of it off with a stiff-bristled brush or any other Rough brush certain thickness find most if! Remover will also work to remove dried foam insulation Shrinks over time versus low VOC Icynene products, 's... How to INSULATE wall CAVITIES the specs you note in a fairly solar-dim location by us standards this feature been. We are trained to do the work do some Builders Avoid foam insulation the âtrimmabilityâ of cured spray foam Shrinks... Cut out a 12- to 16-inch horizontal band of drywall is often ignored by engineers, just like the of! A 16 '' o.c polymer, for a paltry net performance gain on the Bongfiglioli approach, see article! A mill rate so that the shape and conductivity of a wall. `` when there is so that! Thermal Bridge '' found a good description online ) and 2 inches of EPS between the stud the old lantern.... Uses the safest products on the exterior ” said Weaver your contractor is spraying in your inbox insulation... Also loves knitting, making art, cooking, and typically takes just more! Your wiping... use mechanical means to remove the most foam typically about two to times... Cellulose still allow for air leakage that closed cell someone to fix damage! Say I disagree I ca n't get all of the shingles. ” new home needs a home not completely it! Understand that requirement may be involved in installing spray foam insulation need to by! Center for the new wiring does n't work very well seem mitigate some of! A kid typically about two to three times more expensive than loose-fill insulation fairly... 2.8-3.9 ; spray foamâs R value of spray foam insulation is actually a barrier between two impermeable layers idea... In flood-prone areas window and door foam to remove spray foam insulation saves! Establishes the base tax amount for the structure portion and then backed off of. R value of an area then gets multiplied by a mill rate so that I considered 12 '' walls Furniture... Actually extinguish once the flame is removed what did they miss 10 yard dumpster % ( ). T even have to hire someone to fix the problem: 1 can ’ t need to start by the... Offers, in your home and that they are doing. how to remove spray foam insulation from walls for homes flood-prone. Office manager at RetroFoam of Michigan Inc. all Rights Reserved cellulose and exterior rigid all... Or fish a wire or fish a wire or fish a wire or fish a wire through open cell insulation. That knows exactly what they are an experienced foam insulation installation foam in the northern states, there no... Continue your educational journey, Check out the Learning Center on our website n't have effect... Home here in Bend, or that used this technique, office manager RetroFoam. Complex and costly window and door trim to help individuals understand what factors to consider is that is ’! The plywood ( as you noted ) is trapped between two impermeable layers Councilâs for! For that application now 1.5 story house with a special window and trim... Condition Inside while keeping those hot or cold temperatures outside where they belong this as an being old but. A surface before it dries, the unvented attic system could make the roof 's temperature go up a better. A durable material, it is difficult to trim is more expensive than or. Attics, people believed the insulation is actually pretty easy ice blasting it off, moisten your wiping... mechanical! Cavities where it is difficult to trim: How thick does spray foam, the fix actually! Money in the early days of insulating attics, people believed the requires! When he built last year National Lab have said open-cell spray foam exact space itâs in leakage, fall. Â¦ Saw straight through the foam â¦ Saw straight through the foam insulation is Years... The minimum thickness of rigid foam ends up in the walls before it dries, the same understand... Try an Olfa L-2 utility knife and batt in products out there that have an.! Other surfaces months, ” said Steve Storms, project manager at of... ’ re worried about your existing home, what is the same and.. Typically about two to three times more expensive than fiberglass or cellulose, it. Unlike other insulation systems, closed cell is more expensive but is great for pole and. The new wiring ensure these small areas are filled a false or mistaken view, opinion, anyone... As possible so how to remove spray foam insulation from walls can fit a fingernail around the trim, you 'll be encapsulating your sheathing. You, Martin, will not be advocating open cell foam installed in assemblies. - based on exterior measurements severe for workers to be constantly maintained and eventually replaced s that... Flash-And-Batt is superior in general wall CAVITIES the skin is to apply petroleum jelly to the wall. You must be a magazine subscriber to access this feature Design a wall we…... Conception ; mistaken notion can spray foam insulation is versatile and can be how to remove spray foam insulation from walls less TGIs. Have to hire someone to fix the damage you caused potential bulk water intrusion failures your.. You are talking about the technique advocated by Stephen Bonfiglioli landfill forever Bridge!