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What type of insulation on brick wall above suspended ceiling?

Barry_E | Posted in General Questions on

I have an older building with brick exterior walls. One side joins another building and is occupied so no need for insulation on it. The opposite side of the rectangular shaped building is exposed. It faces south east with nothing but a coat of paint on the exterior. Inside of this wall it has a 2×4 framed wall that only goes up to the suspended ceiling. There’s 27 inches above that up to the original ceiling that is not insulated. The wall was plastered and has since (at least above the framed wall) delaminated. It was coming off in chunks so we just removed it all and repaired the suspended ceiling.

I’m wondering if I should insulate that part of the wall and how it would be recommended to do so?

I have some 1/2 inch blue board that I can re-use there if it makes sense? The framing stops at the suspended ceiling so I would have to frame to use fiberglass. I’m trying to do this the easiest/cheapest way but don’t want to let a penny cost me a dollar?

I’m also not sure if the plaster was coming off because of moisture coming through the wall or condensation from not being insulated as you can see a shadow of the area along the outside wall that mirrors the space inside.

I appreciate any advice you feel inclined to share.

Thank you.

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  1. GBA Editor
    Martin Holladay | | #1

    First of all, can you tell us your name? (I'm Martin.)

    Whether or not it's a good idea to insulate the interior side of an exterior wall on an older brick building depends on many factors. To read all about these factors, and about ways to safely insulate older brick buildings, see this article: "Insulating Old Brick Buildings."

    If an evaluation of the following factors are favorable -- (a) your climate, (b) inspection of the water management details on the exterior of your building, and (c) an analysis of the water absorption qualities of your bricks -- you can insulate the interior of your walls with closed-cell spray foam.

    If you go ahead with interior insulation, the insulation is needed in at least two locations -- (1) above the suspended ceiling, as you noted, as well as (2) below the suspended ceiling, where there is now a 2x4 framed wall.

  2. Barry_E | | #2

    Martin, thank you very much for the reply. My name is Barry, I'm new here and haven't learned to use the site just yet. I'll try and figure out how to use my name in a post.

    I'm in the north west corner of North Carolina, elevation around 2800'. I am not sure what zone that is but it does get cold here. Below zero sometimes. The wall is insulated below the suspended ceiling. I'm sure there has been moisture penetration from the outside but also feel there must be condensation in the uninsulated space also. I get different answers when I've asked contractors in my area for advice. I believe many aren't educated as myself in this area. I'm sure it needs insulated but how might be very important, trapping moisture and causing more problems is my concern.

    It is heated with an oil furnace, forced air through flexible ductwork above the suspended ceiling. Cooled through the same system.

    I will take a few photos today of the project to make it more clear and again, I appreciate your response.


  3. GBA Editor
    Martin Holladay | | #3

    As my article makes clear, this is a situation that we can't solve for you over the internet. There are lots of factors at play. If your winters go below zero, you have to proceed carefully, since freeze/thaw damage can destroy a brick building -- especially if the bricks are soft and the walls get wet from wind-driven rain.

    I advise you to follow the advice in my article.

  4. Barry_E | | #4

    Here are some photos to help explain the situation. The brick and mortar are in pretty good shape even though some of the bricks face have popped off from freeze thaw. I'll get that repaired and a nice coat of paint to seal from rain penetration.

    I haven't had a chance to read the link you provided but I will make an effort to read it tonight.

    Thanks again.

  5. GBA Editor
    Martin Holladay | | #5

    If your bricks are already suffering freeze/thaw damage, that's a bad sign.

    The wall in your photo is totally unprotected by a roof overhang, and therefore at the extreme end of the spectrum when it comes to rain exposure -- which is to say, it gets soaked. That's also not a good sign if you want to insulate the wall on the interior.

    Read the article -- you'll learn more.

  6. Barry_E | | #6

    I read the article and wanted to say, "you're the guy I've been looking for"! Very enlightening article and answered so many questions that were floating around in my mind.

    The exterior wall in the photo has (5) five openings or flues. Four of them have chimneys and one is just a hole where a metal flue was. The insulation used is fiberglass batts and it seems to be causing all the problems listed in the article. I wondered why, where there was no insulation on the walls the plaster was in great shape but where it was insulated it coming off in large sheets. Makes sense now.

    I have someone who wants to rent the space and wants the brick exposed as it's much nicer to look at than drywall. I told them they could but the cost of heating would likely climb very high. I may go over that with them again now.

    I may look at doing the insulation on the outside with the system mentioned in the article. That would take care of painting every few years, look nice and insulate all at the same time. Win, win, win. I have some thinking to do. I also have a block building that's uninsulated with plastered walls that I had decided I wanted to insulate from the outside.

    I really appreciate your helping me understand this problem better. This is exactly what I was hoping for when I joined the site.

    You may get tired of me asking questions because I think I have found the tree of knowledge.

    Thanks again,


  7. Barry_E | | #7

    Double post,,,

  8. GBA Editor
    Martin Holladay | | #8

    Thanks for the kind words. And welcome to the GBA community.

  9. Barry_E | | #9

    Martin, I have another question. While reading the comments about the article you directed me to, I noticed someone mentioned that using eifs was a bad idea because of fail points. I guess that's obvious as any system has weak points and need to be done correctly.

    I dont think we have any eifs contractors in my entire county. I'm a hands on person who would consider doing this myself as I mentioned I have two buildings that could benefit from this system. I contacted one company that's a few hours away and they did look at the building, then never returned. That seems to be a constant in my area. The other problem is the contractor who knows less than I do but won't admit it. I have done construction work and remodeled a home, (while living in it) wait that might show how stupid I am rather than how capable.

    I am willing to study this and try and learn the proper techniques to apply this product. One reason is to make sure it is done correctly as I have very little confidence in contractors in my area. I know how I possibly sound about now. I have owned an operated afoundation waterproofing business and was very unimpressed with all but a few contractors and even those were questionable depending on the subject. Our building codes have just started to catch up with surrounding areas and even then it's the (minimum) to be used or performed. Everything seems to be old school here and by that I mean old school as in uneducated, poorly done. Not old school high quality.

    The question,,,,,,, actually a few. Why would I not want to use eifs, potential problems or failures on masonry buildings? Where can I find resources on the best way to apply the product/s? I looked but did not find videos on this site for the above.

    I understand why you might say "just consult a professional and not try this" and that may be the best advice. I'll know as I do a little deeper if it's something I'd want to perform on my own. I'm pretty independent as you have to be in my area if you want things done correctly. Just assume I'm capable for arguments sake ;) .

    Thanks for all you have answered so far and I appreciate any help on these new questions if possible.

  10. Expert Member
    Peter Engle | | #10


    As a certified third party EIFS inspector, I review about a million square feet of EIFS a year. I think this gives me at least a little bit of cred.

    That said, I think this is definitely something you can try at home. Most of the installers I see have little to no skill when they start with these materials, and the manufacturers have tried to make them as foolproof as possible. There is a fair amount of equipment cost, with a wide variety of stainless trowels, mixers, etc. You can rent the scaffolds, and possibly even have them erected by the rental company. That would save you a lot of time and effort.

    I have no particular favorites as far as system manufacturers. Find out who has the closest distributor in your area and use that system. The distributor will be happy to also sell you a full suite of installation tools and equipment. For a brick or block building, you will need to scrape, strip, or otherwise remove as much of the loose paint and plaster as possible. Use a system with a roll-on weather barrier, and vertical ribbons of adhesive to hold the foam in place. More foam is better. Each manufacturer publishes a book of installation specifications and a whole set of graphic details for pretty much every sort of edge and penetration.

    Your biggest challenge will be the roof. You will need to remove and replace the parapet caps, with roof membrane wrapping up and over the cap, and a new sheet metal or other cap over that. You may want to work with a designer on the details, or take a look at the details provided by rubber roof membrane manufacturers. One options is to also put EIFS on the inside of the parapet walls to help keep them dry and warm(er). You still need new parapet caps to keep water out from behind the EIFS.

    Done properly, EIFS is a relatively durable product, and it does keep the walls warm and dry. You never know. Once you've done one building, you may decide you've found a new line of work.....

  11. GBA Editor
    Martin Holladay | | #11

    As my article on insulating old brick buildings indicated, EIFS is a great way to insulate this type of building. Exterior insulation is vastly preferable to interior insulation.

    The EIFS failures from the 1980s that many people remember were all wood-framed buildings, and the failures were due to flashing problems and the lack of a rainscreen gap.

    I trust Peter Engle's judgment when he says, "you can do it." My only hesitation has to do with requirements for installers to be certified. I was under the impression that EIFS materials manufacturers were leery of letting homeowners install their products, and that these manufacturers had all instituted requirements for installer certification.

    It's also worth checking with your insurance company. Some insurance policies have EIFS exclusions, or require any EIFS to be installed by a certified contractor.

  12. Expert Member
    Dana Dorsett | | #12

    The northwest corner counties in NC bordering on TN are all zone 5A (from Yancey county on up to the VA border). Those would be the green counties in this map:

    With an EIFS approach the insulation is continuous, and the thermal mass of the brick counts, making it a "mass wall" by code definitions. With a mass wall as little as R13 all on the exterior would meet current code, or R8 on the exterior + R5 on the interior, any ratio will work as long as at least 50% of the R is on the exterior side of the wall. At outdoor temperatures that matter 3" of Type-II EPS would hit R13, even though it's labeled R value would be R12.6. At 3.5" it would be labeled R14.7, removing all question.

    For sections of wall that would not have exposed brick on the interior you could drop back to 2" of EPS on the exterior (R8.4) , and install 3/4"- 1" of continuous foil faced polyiso (R4.6- R6.5 ) on the the interior side, strapped in place with furring through-screwed into the masonry onto which the wallboard can be mounted.

  13. Expert Member
    Peter Engle | | #13


    As far as I know, none of the major suppliers require certification to buy the materials. They do require certified installers if you want the manufacturer's warranty.

    The IBC requires special inspections for EIFS, but not if it is installed over masonry, and not if it incorporates a WRB. Of course, local codes may vary.

    You are right that some insurance policies have EIFS exclusions. I mostly see this in homeowner's policies, and even then, most companies only exclude EIFS without a WRB. I have not seen any policies that require EIFS to be installed by a certified contractor. YMMV.

    I do think that a motivated and reasonably skilled person can learn the requisite skills to do a passable job of installing EIFS. There are some good resources at AWCI and EDI to train installers and inspectors. That said, this will be a lot of work and progress will be somewhat slow. I think the biggest challenge will be getting a good looking finish. Barry should definitely start where it won't show. With only one applicator and while learning, applying the finishes will be slow and it will be difficult/impossible to avoid cold joints where the material has dried before adjacent material is applied. Pros install V-grooves in the foam when they can to limit the size of panels that need to be finished at one time. Rasping/flattening the foam also takes some skill and reasonably good eyeballs.

    I think the benefits of EIFS on a building like his makes the effort worth a try, since he doesn't seem to have too many other options locally, and since the building is suffering in its current state.

  14. Barry_E | | #14

    I never considered cold joints. That's the kind of thing you learn about when it's too late. I won't attempt this without studying and trying to learn all I can. I would even consider helping someone who does this professionally for free just to learn the ins and outs. As I said I have two buildings that need this. One is thirty feet by forty feet with one marriage wall and the one in the photo that's seventy feet by forty.

    I found a fellow a few years back who was experimenting with closed cell spray foam applied to the exterior of buildings and he had figured out a way to shave it smooth. He had even done this to a towable camper. I think he died of a heart attack and I haven't seen anything since. Seemed like a good idea to me but I don't understand the entire concept, obviously.

    I thank you all for the info as it's really nice to get information that's accurate.

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