Flash and Batt insulation....yes, no, maybe
Kaiya Price
10 years ago
The footings will be going up on my home at the end of January and I requested spray foam insulation. My builder suggested that I consider flash and batt to keep costs down (my house is 5,465 sq. ft. Including unfinished storage space). I began to research flash and batt and as of 2011 some builders and homeowners began to see problems with moisture and condensation in the walls. I live in the mountains in Va, does anyone have any input on this? I would like to get as much info as I can so I can make an informed decision. Thank you.
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Kaiya Price
Original Author10 years agoThank you very much ReSquare and Fred. My home is going to be stucco and stacked stone so I thought that would have to be considered as well. I will definitely be doing more research, so far I'm planning on asking for only closed cell spray insulation, that seems to be what most professionals are recommending.
PROReSquare Architecture + Construction
10 years agolast modified: 10 years agoClosed cell foam has many good applications, we specify it a lot, but it *can* be inappropriate in certain situations where vapor migration through the wall is actually desired and necessary. Closed cell foam is essentially a thick barrier blocking vapor and moisture migration through the wall, but if the exterior skin acts as one as well (eg: stucco painted with elastomeric paint, or a housewrap with insufficient vapor permeability) the two act together to trap vapor in the wall. If that trapped vapor is not anticipated and mitigated, it will turn into moisture and deteriorate a wall in short order.
I think it's great you are doing your own research, and I encourage you to keep at it; "an informed consumer is our best customer"! But in the end, my recommendation is still to take that research to a qualified design professional like an Architect in your area that knows the specifics enough to make the best recommendation for you.
User
10 years agoThat is funny. I have been arguing with architects for some 20 years on this very subject, including EIFS, and some of them are just starting to get the picture now. LOL- PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years ago@FredS: Not all Architects are focused on building science, letting engineers (or at times, no-one) carry that burden. I think that's a shame, always have. Coming from an combined Engineering and Fine Arts background, building science and art to me have always been two partners in the same dance.
EIFS is a great system that has gotten a bad rap. It is an excellent whole building approach to energy efficiency, especially in masonry structural systems (thermal mass internal to the thermal envelope.) And it's failures have been mostly in the failure to understand how it works, and as such installing it (either in means or in design) improperly. The failures are not inherent to the system itself. Even the early failures were not inherent to the system but to the failure to provide for moisture weeps during installation at window heads. We see the very same failures still occurring with new stucco installations today, but no-one blames the stucco and rightly so. Not knowing how the product works is usually worse than any inherent problems with the product itself.
"Flash and Batt" is a perfectly acceptable value engineering approach to a closed cell spray foam wall design. The issue I see is whether the vapor profile engineering will be done to assure it doesn't turn into a moisture factory. The design assumed a wall cavity completely filled with closed cell, and it is now being filled with some permeable batts. That's a huge shift in the design. Some flash and batts approaches only flash the perimeter and the penetrations. That creates a varying vapor profile, which in turn can have moisture condensing in a variety of places within the wall. Others that flash the entire exterior face do it with an inappropriate depth with the same results. Others do it to the right depth but might add a VB on the winter warm side either as Kraft paper because it's easier to staple up that way or because they always have done so with batts in a bathroom, either way causing all sorts of internal moisture problems.
No knock on Contractors (I am one!) but most don't perform vapor profile re-engineering when offering a less costly alternative like flash & batt. They see it being done, they learn a little about it, and then they offer it as a cost savings solution. But they don't necessarily do the engineering required to make it a well-designed one. That's the same sort of mistake that caused so many of the EIFS failures. My cautions here to @mommydecor are to question those offering solutions, using her research. As I see it, the *most likely* qualified pro to really understand this will be an Architect, but that doesn't mean a good GC won't be better at it. Just going with odds. - PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years agoPS, as Disclaimer: We have not installed a flash & batt system. I have not done the engineering on one. That said, knowing what I know about wall vapor profiles, I'd actually question the use of closed cell foam in flash and batt rather than open cell. Seems to me the addition of a closed cell layer somewhere in a permeably insulated wall cavity is asking for trouble, especially when its thickness dictates the dew point and that thickness is left to the vagaries of installation. My gut says use of open cell and a fixed VB if necessary would be a more technically sound design. But that's a guess, and one I'll be studying further, you can bet on it! User
10 years agoI closed a business applying EIFS overnight back in 1989 because the architects would not spec it to be installed properly or design the rest of the structure to accommodate it. Ie roof overhangs, flashing details and wall cavities. Even stucco is supposed to have a weep/drainage/screed system behind it when applied to an insulated wall with conditioned space inside. THIS is what makes the installation proper. Open cell foam would not be a good alternative because it holds water. Most open cell applications have been found to break down over time. If a full fill closed cell application is a problem in ANY climate, then it is the fault of the stucco or other cladding being installed improperly. Not the use of it.
R703.6.2.1 Weep screeds. A minimum 0.019-inch (0.5 mm) (No. 26 galvanized sheet gage), corrosion-resistant weep screed or plastic weep screed, with a minimum vertical attachment flange of 31/2 inches (89 mm) shall be provided at or below the foundation plate line on exterior stud walls in accordance with ASTM C 926. The weep screed shall be placed a minimum of 4 inches (102 mm) above the earth or 2 inches (51 mm) above paved areas and shall be of a type that will allow trapped water to drain to the exterior of the building. The weather-resistant barrier shall lap the attachment flange. The exterior lath shall cover and terminate on the attachment flange of the weep screed.
The fact that you say that the stucco would block moisture migration does not help your case of an architect being appropriate for anything. Just because it was applied directly to the structure successfully 60 years ago when they didn't use insulation doesn't make it right now. It needs to be applied the same way EIFS and fake stone should be.User
10 years agoP.S. I have never been foolish enough to install a flash and batt, but I have witnessed the failure first hand on both open and closed cell installations. The open cell just holds the moisture better that the batt allowed in and causes a quicker mold problem. If you put a vapor barrier on the inside of the wall AND put enough open cell foam in to get past a dew point that fluctuates too much to actually accommodate, then you have still effectively created two opposing vapor barriers. Neither one good enough to stop the flow of moisture into the wall due to barometric pressure or the use of a large range hood.Kaiya Price
Original Author10 years agoWow, you both are giving me lots to research, I love it!!! I'll be coming back for more questions. Thanks again.User
10 years agolast modified: 10 years agoJust so you know, I would not actually recommend anything but just fiberglass batt insulation and one properly placed moisture barrier. A house is going to breath no matter what you do. That transfers moisture. Better to plan for moisture than to think you can keep it out over the long run.- PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years ago@FredS:
"The fact that you say that the stucco would block moisture migration"
Never said any such thing. And not sure why you're on my case like this. I'm not questioning anything you've suggested, I was supporting your points.
"I would not actually recommend anything but just fiberglass batt insulation and one properly placed moisture barrier."
Except this one. Do this in certain micro climates & wall construction profiles and you'd be creating a failure prone situation.
"That transfers moisture."
And this. Air transfers only vapor. Moisture transfers only by gravity or capillary action.
*Any* thermal barrier design requires careful analysis of the vapor profile of *that* wall construction design in that *specific* climate location and building environmental control system. Just about any insulation, vapor and moisture barrier materials can be appropriate in many locations with a variety of building environmental control systems. It's how you put them together that determines the robustness of the final design.
My only point to @mommydecor is it is complex, and her own personal research, while highly valuable to informing her in her decision process, cannot and should not be the only thing she relies on to make the decision unless she herself is a building science professional. It takes a local pro to truly sort out what the best solution is, and one well versed in analyzing wall vapor profiles. User
10 years agoMaybe this doesn't mean what it sounds like? "(eg: stucco painted with elastomeric paint, or a housewrap with insufficient vapor permeability) the two act together to trap moisture in the wall." The two should not work together to trap moisture, they should be working together to "carry" it away. Thus the weep screed. Asking an architect their opinion will not get the job executed properly, and that is the important part.
I doubt those micro climates are likely to exist in VA. and a single type of insulation with one moisture barrier has always proven to have the best outcome in the long run. Now your just being silly.
Vapor becomes moisture in the walls. I don't think it matters what you call it before it gets there. The moisture is what causes the problems.
Insulating a house is only a problem because people keep coming up with these Frankenstein solutions. I certainly would not rely on just one local professional that thinks they have come up with the "better mouse trap". Professionals from 30 years ago learned better and now the new generation will think they know better and make all the same mistakes.- PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years ago@mommydecor:
Sorry to sort of hijack your thread with FredS.
So that you know some of the basics of what we're bouncing around about:
"Vapor" is the presence of water molecules in air but in a gaseous form. Think of humid air as being high in vapor. Pretty much all air contains vapor and colder air can hold less of it than warmer air.
"Moisture" is wetness like rain and condensation.
A "vapor barrier" in your wall is a layer that prevents air from moving through it, along with its vapor. Think of a the vinyl skin of a rain coat.
A "moisture barrier" in your wall prevents moisture (drops of water) from passing through, but allows the transfer of air (with vapor). Think of a vented raincoat, or Goretex.
"Insulation", in whatever from, prevents the transfer of heat, but not necessarily air, vapor or moisture. It's the sweater under your rain coat.
A "vapor profile" is the theoretical description of what your wall's construction will do to the presence of water vapor in the air that gets into your wall across the width of the wall whose temperature varies across that width.
As air finds its way into your wall, and there is a temperature difference from one side to the other (warm inside during a cold outside winter) the vapor in the air can turn into moisture. Think of a cool glass of water in the summer heat: the outside of the glass becomes wet because the cool glass contacts air carrying moisture and the temperature of the glass is cool enough to force the moisture in the air to condense. That's ok on a glass of water, but NOT ok inside your wall.
The best way to put all the pieces together in a wall construction to keep you warm in the winter, or cool in the summer without creating condensed moisture in the wall is a delicate balance that is dependent on the variable humidity & temperatures your home is expected to be subject to throughout the year, inside and out in all various combinations. A good wall design will control the transfer of heat and vapor with a vapor profile that does not allow moisture to develop inside your wall in any of the possible conditions, or if it does, it is designed to control that moisture's escape from inside the wall.
Flash & Batts mixes two approaches in ways that can cause moisture problems that are mostly dependent on what type and how thick the spray foam is. 1/2" too thin and you get moisture at some point, and since that moisture is surrounded by batts which act like a big sponge, that's where the moisture stays and rots out the wall, grows mold, etc. Its a risky approach that depends highly on not just the right design thickness of foam, but then the right installed thickness. That's a lot of variables that can go wrong rather easily. User
10 years agoAnd to add to what Resquare just explained, the amount of foam insulation required is actually in the International Building Code, but I have done the math and it would have failed for one straight week already this year where I am. To add to that, when they spray the thinner layer of foam, it is uneven leaving extra voids the facilitate condensation. The theory also does not take into account the temperature where the foam, batt, and framing members all meet. This is the coldest place and the weak link. It is this location where the condensation occurs and the wood (cellulose) allows for mold, rot, etc.Kaiya Price
Original Author10 years ago@ReSquare....please don't think you are monopolizing my discussion, I'm really appreciative. This is exactly why I posted this question because it was overwhelming at times to me. I chose a house plan from Eplans but made sure to pick a plan by a very good architect (Visbeen is who I chose).
Because I live in Thomas Jefferson country in Va, surrounded by vineyards, I REALLY have to pay attention to the climate and insulation; not to mention allergies my family has to live with and my mother has a auto-immune illness. I'm building as green as possible (no LEED cert. though), and I do know insulation is a huge part of a green decision....so please post away. That goes for you as well Fred S.Kaiya Price
Original Author10 years agoNew question....since my house is being started at the end of January, what do I need to do to make sure the insulation is installed properly, regardless of what insulation I decide to use?- PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years agoWho was it that said designing to code is like designing for the bare minimum of what it takes for it not to fail? IBC thermal values have nothing to do with and make no accommodation for or reference to vapor profile design. Anyone that assumes they do are not doing their job as a designer.
"R703.6.2.1 Weep screeds. "
Says nothing about weeps at window heads, vertical/horizontal transitions, bowl conditions, etc. We have fixed more structural failures than I care to think about caused by lousy stucco detailing that had no guiding code requirement. It was simply bad craftsmanship and a complete failure to understand how moisture migrates behind stucco, and in most cases that it WILL do so, by design.
"stucco painted with elastomeric paint, or a housewrap with insufficient vapor permeability"
Key word: "or".
A housewrap (moisture barrier) with insufficient permeability fails to allow vapor out from behind the barrier. It traps vapor INSIDE the wall, behind the moisture barrier where it should have been allowed to breath out but will now condense. Usually presents as rotted exterior wall sheathing, sometimes as finish veneer delamination from rotted sheathing.
Stucco painted with elastomeric paint with no permeability will prevent moisture in the stucco from breathing OUT. If it was applied as a parge on a wall profile that assumed that vapor in the masonry would migrate out, the elastomeric paint will prevent that migration and trap vapor in the masonry, eventually collecting enough to become moisture in the wall. Usually presents initially as bubbling of the paint, later as spalling of the stucco, and finally as deterioration of the CMU, and most prevalent on walls facing to the sun.
"Asking an architect their opinion will not get the job executed properly, and that is the important part. "
No, but it has a better chance of assuring it gets executed properly than without one, especially when that Architect renders more than an opinion by detailing it, and backing it with his license, reputation and E&O insurance. That's just as important.
"Vapor becomes moisture in the walls. I don't think it matters what you call it before it gets there. The moisture is what causes the problems. "
There are more ways for moisture to get in a wall than vapor, so what you call it before it gets there is very important if one is looking to control that moisture's movement. The difference between a moisture barrier and a vapor barrier make all the difference in a vapor profile. Insisting that a flash and batt proposal should NOT have a vapor barrier without first confirming the flash proposed is full-stud width closed cell can actually CAUSE a moisture failure if the flash is open cell and/or is "joints and penetrations only" and the conditions warrant the VB. So ... yeah... I think it's important to make the distinction.
"I doubt those micro climates are likely to exist in VA"
You may well be right in your assumption. But that's the difference between us here: I'm not prepared to make recommendations based on an assumption that could be wrong and cause a building failure in someone's home. If I'm going to recommend a specific solution for @mommydecor it will be under contract, having reviewed all the relevant specifics. As should be done by any qualified professional, hence my recommendation for her to find one locally.
My point is unless someone is reviewing all the specifics of @mommydecor's situation, they are bound to make a damaging assumption. The best thing she can do to make the right one is find a local qualified professional to help her directly. Research on her own is a huge plus because her learning about it will help her sort out the ones that know what they are talking about from those that don't. - PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years ago@mommydecor:
Under all circumstances insulation and the wall in which it is being installed should be dry, and should be sufficiently protected to stay that way once installed. Winter in VA can make that difficult to achieve unless the entire home's exterior envelope has been completed: roofed, glazed, sided and flashed. There are other important factors, but they are specific to the insulation being used. User
10 years agoWell, that can be just as tricky as deciding what to use. Not only can there be installation problems with people, but the weather can play a factor. Not only the immediate weather and moisture, but building materials expand and contract through the different seasons. So, even after the job is done, you need to make regular inspections to ensure that things like caulking have not been compromised and bushes are not growing up on the house to hinder air flow.
As for the building process, have a conversation with your builder to let them know you are watching, and go make personal inspections regularly. The other option may be to hire an independent inspector to check on it for you, but then you need to make sure they know enough to be worth it :-/Kaiya Price
Original Author10 years agoSo stucco is very pretty, but I know I could also use brick. I had no idea that stucco was so in depth, I just figured it was similar to brick. Silly me, lol.User
10 years agolast modified: 10 years agoThe overall point that you need somebody very knowledgeable in your specific area to review this still stands and is the most important part, but so is the actual installation :)
As more insulation is required in houses, more problems occur with what used to be what some were calling standard building practices. The "code" doesn't keep up very well and leaves too many loopholes for error. Everything needs re-thought and the stragglers need some help in the right direction. That is why I'm here.
I have had builders , one architect/builder and homeowners quote this to justify their flash and batt and warm roof installations; TABLE R806.5 INSULATION FOR CONDENSATION CONTROL. I am not going to compare it to other standards at the moment, because I still don't buy it anyway. At some point, (the one I would be happy with in my region) you may as well finish the rest of the cavity off with foam.
I doubt we are talking about applying stucco to masonry here, and you know very well that the inherent problem with flash and batt is with the water vapor turning to moisture, not the "other" reasons for moisture.User
10 years ago@mommydecor it isn't so much about whether you use stucco, but how moisture is controlled. This encompasses how long you take a shower and if you use the exhaust fan, Whether you use a range hood and if you have a good amount of fresh air exchange from outside, how big the house is and how often you open the front door.
Unless you get a De-humidifier on an accurate sensor and a whole house air exchanger, the flash and batt is generally the most troublesome system in regular use. Even if constructed in the best method possible. Dew points change with relative humidity caused by everyday activities. IMO it is too much to try to keep on top of.- PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years ago@FredS:
"The overall point that you need somebody very knowledgeable in your specific area to review this still stands and is the most important part, but so is the actual installation"
Is the nail on the head and about the only advice I see that we can give @mommydecor that doesn't unnecessarily risk making things worse or causing harm.
I'd also be happy to continue to discuss vapor profile science here but I doubt it's helping @mommydecor all that much at this point in the tit-for-tat format it has been driven into, so respectfully I end my part of it here.
My position remains as it has been:
@mommydecor, I think the best thing you can do is continue your research so that you can contract with a qualified local professional for some specific guidance with an understanding of the issues. I believe your best chance at finding such a professional is with an Architect, but that doesn't mean it has to be one on this issue. A GC that understands the issue would obviously be far more useful in this particular case. But the odds are much better with Architects since something like vapor profiles is part of our professional training along with all the other overall services you may need in assuring your home's construction meets the design intent and requirements.
I actually believe it is very important for you to have a consulting third party on board besides just you and the GC if you will be taking stock plans and changing them like this. They were designed as a package, and when you change one piece in the package, there can be repercussions only a design professional can recognize in time to change them on paper before something is built wrong. This insulation issue is just one that you happened to stumble upon. Why risk missing others? Architects are specifically trained to do just that.
The one thing I'd caution you on the most is from taking specific design/science advice from people on the internet whether it is on this site or any other unless you confirm their credentials (both professional and legal) to be dispensing such specific advice and they in turn work with you in great detail learning all they can about the details of your home's design, location, structure, systems, etc. before proclaiming they have your solution.
Everyone has an opinion, but licensed professionals are legally bound to make sure theirs is correct and to bet their license to practice on it. That the unlicensed are under no such legal restriction is an adversely perverse consequence of law that escapes most consumers. Your best course of action as I see it is to contact some local Architects, discuss your concerns with them, let them know your budget, and see what services they can offer to help you best realize your home's construction with as few bumps in the road as they can help you avoid.
If you have additional questions, I'm happy to stick around and advise, but, per above, you have to realize I can't give specific design advice, just general knowledge and then point you in what I think is the right direction for you to get your specific solution.
Don't worry! With the right team your new construction should meet all your expectations! 
PROSims Construction
10 years agoBatt insulation if do not have a well sealed envelope is just a good air filter. That said what works at altitude is Colorado is not what will be good for you.
Building Science is a foreign language to many builders but not all and many are even more up to date than the so called professionals.
I do not consider my self an expert with all insulating systems, building the SCIP thermal mass system I use out preforms so many of the standard insulation systems. There is new information coming out all the time. I find the loudest posters to oppose thermal mass make a living using a product without thermal mass.
I have been accused of building over insulated homes, but consider moving from a two story home with a $150 monthly bill. Then moving next door ( 5' away) to a larger three story home and dropping you bill by 60% . I say over insulate that.
- PRO
Sims Construction
10 years agoTwo story home on left new Three story conditioned five level home on right. Kaiya Price
Original Author10 years ago@ Sims Construction...can you tell me about SCIP? I briefly read about it. Thank you for your input.
bubbasgma
10 years agoTerrific discussion! Thanks for sharing your insights. A link to Joseph Lstiburek
http://www.buildingscience.com/search?SearchableText=insulationbubbasgma
10 years agoYou're very welcome, mommydecor. Repairing flood damage here and have gotten so much conflicting advice with wildly different costs. Makes my head spins!Kaiya Price
Original Author10 years agoI ask a ton of questions. It helps me research better, the pros and the cons. I'm spending hard earned money to build my forever house, and I want to make sure I am as knowledgeable as I can be in order to make good, sound decisions.User
10 years agolast modified: 10 years agoHere is the problem with flash and batt theory.
http://www.buildingscience.com/documents/digests/bsd-controlling-cold-weather-condensation-using-insulation/?searchterm=insulation
If you read carefully, they want to design a building in Toronto Canada for a low temp of 25 degrees F. This alone is a bogus number.
http://ww2.nationalpost.com/m/wp/blog.html?b=news.nationalpost.com/2013/01/23/toronto-posts-coldest-temperatures-in-two-years-as-wicked-cold-snap-continues-to-grip-ontario
It actually gets some 40 degrees colder than that for weeks.
They also want to use an unreasonably low relative humidity level of 35% when most people prefer 45% and without a De-humidifier, will often be even higher.
This plays havoc with these theories the pencil pushers like the building science web site and the real world experience is now proving that. Once the moisture gets into the cavity, it is hard to get out. It is no longer vapor that can be carried out with the air and the foam blocks the exit path anyway.
One good thing about SCIP is the lack of cellulose to cause mold, etc. And nothing to rot, at least in that part of the construction.bubbasgma
10 years agoStrategic and Competitive Intelligence Professionals-?
Society for Computers in Psychology?
Maybe it's time I just move to a condo?- PRO
ReSquare Architecture + Construction
10 years agolast modified: 10 years ago@mommydecor
Do you have an Architect or other qualified local building design professional working for you to help you make these decisions? Learning about all these issues yourself is commendable, but a design professional has spent *years* learning about these things and would be an invaluable resource well worth any modest fee. Think of the fee as insurance against making a huge mistake on your own that costs ten times the fee to fix later. 
Lizabeth
10 years agoJust a suggestion for another resource for you to read about the various issues regarding insulation would be Green Building Advisor. Yes you of course need professionals but getting enough back information to have a meaningful conversation with a professional is important for any homeowner. Good luck in your build.
Building science and code and vapor barriers have befuddled many over the past decades as energy costs have risen.- PRO
ReSquare Architecture + Construction
10 years ago@mommydecor
One other thing about insulating and winter construction is to be sure that any framing that is done is not directly exposed to significant moisture (like rain, snow, etc.) If it is, it needs to be allowed to thoroughly dry out or, worst case, replaced before it is closed in. Moisture is a building's worst enemy and if you built it into the walls form the outset, the building starts out with two strikes against it out of the gate. Kaiya Price
Original Author10 years ago@ReSquare....I have one of the top builders in my area. He's certified and very good. My only issue is the insulation, and I need to be as knowledgeable as I can. My builder can suggest things, but at the end of the day, it's my money.
K. Brown
10 years agoGreat topic mommydecor . I am reading with great interest. Currently building a metal storage building and also metal cabin. Will be using spray foam insulation. Trying to figure out between open or closed cell.- PRO
Sims Construction
10 years agoMommydecor I have some basics information about the system at. http://simsbuilt.com/SCIP_System.html.
The system is built around the world and of the 57 factory's I have found and I am sure there are more only one full time in the US where the panels are made in the US. Recent studys show R26 thermal mas walls out preform R56 standard insulated walls.
Feel free to ask anything Marry Christmas and a happy well new year Richard richard@rsimsco.com
Pictures below show fire protection and two homes that survived hurricanes on you see the floods even took the earth from below the home.
Kaiya Price
Original Author10 years agoThanks @Katherine Rice Brown, I'm glad this info was helpful to others.User
10 years agolast modified: 10 years agoYou can Google these to get a better understanding of what other articles try to summarize or interpret.
gisceu.net/PDF/U721.pdf [PDF] Heat and Moisture Transfer in Wood-Based Wall
Note that they can't even keep 16% of their laboratory models from being defective, let alone an entire house. They also try to use mean temperatures rather than the low temperatures, so it fails when the outside temperatures get below these;
http://www.nrcc.cornell.edu/ccd/nrmavg.html
This one is a standard construction test:
www.ornl.gov/sci/buildings /044.pdf moisture transfer through walls
This is a little about masonry;
users.ntua.gr/.../MOROPOULOU_3.pdf ] A powerful simulator for moisture transfer in buildings
Note that they all talk about the transfer of MOISTURE, not water vapor. Be careful of architects, if they can't dazzle you with their diploma, they will try to baffle you with their B.S.- PRO
Sims Construction
10 years ago"The overall point that you need somebody very knowledgeable in your specific area to review this still stands and is the most important part, but so is the actual installation"
That should go without saying.
Too often I am repairing jobs where the original design was sound until modifications in application and materials were implemented. I am sure without the building department and architects knowledge.
We are so far behind in how we build in the US it is a standard joke at international trade shows that we in the USA can put a man on the moon and still not build a sustainable energy efficient home as the standard model.
Remember many use the codes as the Maximum Standard and some see it for what it is **** The Bare Bones Standards***** We can do so much better. Kaiya Price
Original Author10 years agoThanks @Sims Construction. I intend to meet with my architect after the holiday season and look for additional professional input. In the mean time, I'm still researching, and I'm reading about Passivhaus, very interesting stuff.shenvalleytrans
8 years agomommydecor What insulation recipe did you use on your project? I am building a new house and have the insulation decision to make. thanksKaiya Price
Original Author8 years agoHi Shenvalley,
I decided to use spray foam insulation. I researched A LOT and found it to be the best for what I was looking for. Because of the position of my house (sun rises in front, sets in back) my house could have been too hot causing mold to spread in my walls with flash and bat. So far, so good, but I will say to pay attention to how your house is situated on your lot.
Overall my heating and cooling bills are great, but I also bought really good windows and doors.
Good luck!!
PROArlington Designer Homes, Inc.
7 years agoNo, no, no. There is a lot of good information in the comments and much to be looked at. I would never flash and batt for many of the reasons outlined here. You say you live in Va. I live and build in the DC area and we have the worst of both worlds, high humidity and freezing temps. You need to have someone that understand building science look at the WHOLE SYSTEM.
And as a side note, I would never use closed cell foam on anything that could rot or bend. It is my belief that it traps moisture and it is a fact that it will crack over time as the building cavity shifts and bends. Once it cracks half of the reasons you used the closed cell to begin with are gone.
Lastly, there is nothing wrong with fiberglass if it is installed correctly. But it is never installed correctly.
The answer is: Go with 2x6 walls, air seal it with the proper products and blow in cellulose.
Good luck! Andy.
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