Thread: OT - Anyone have experience with E F I S style stucco

Originally Posted by SteveF

Evidently you are not familiar with the difference in physical properties between a 2" thick piece of XPS foam rated for construction use and a 1/16" thick piece of the cheapest, biodegradeable EPS foam.

Steve

good old water absorbing beaded EPS was used under the stuccos like dryvit 20 years ago. the foam would hold the water up against the crappy tyvek that was full of staple holes leading straight to the shitty OSB sheathing. a real winning system for houses up in the northwest...

We just finished our house with cinder blocks and foam on the outside and inside. Before the contractor applied the styrofoam to the outside he sealed the blocks with some fairly heavy dark grey stuff. This was what the bonded to the adhesive used to hold the styrofoam in place. More sealer, adhesive, then the fiberglass mesh and more adhesive, then finally the colored Dryvit. We have 1 1/2 foam on the outside, the hollow blocks were filled with foam, then 3/4 foam on the inside between hat chanels and 5/8 sheetrock screwed to the hat chanels. Will let you know in a couple of years what I think. Right now the AC set on 80 seems a little chilly. I am not sure how moisture would get through all that stuff to the foam, most of the coatings seem impervious, but we will see.

I read thru this and certainly would not let the professional machinist community design or install EIFS. First EIFS stands for “Exterior Insulation and Finish System”. It has been around for many years and has been successfully installed world wide. Earlier on it had many problems with moisture penetration, vandalism, and fading, poor quality control. You name it. Today most of the problems come from inferior products and unknowledgeable overconfident contractors and manufacturers. Most of the problems installations are residential and many contractors at this level are not qualified to install EIFS. Don’t use them for your commercial structure without checking them out completely including other structures they have done.

If a reputable manufacture is used and the EIFS is installed according to their recommendations it should last about 20 years. Like any product it will need to be maintained like general repairs, repainting, possibly recoating etc.

Reputable manufactures require installers of their products to be certified and educated in the proper installation. Look for an installer who is certified by the manufacture of the product he is installing. This is top of the important list.

For vulnerable areas there are different reinforcing options. Look into them and compare the cost benefits. It might be adequate.

It is absolutely required that the system be properly designed for the climate. Condensation within a wall is a major factor in the failures of this product. Climate of the exterior and interior of a building can cause condensation and damage any type of wall system, not just EIFS. Once moisture gets to EIFS foam it will begin to deteriorate.

This is a good product in many ways and for a 20 year building life cycle is a good choice.

Last get an Architect or Engineer to design the wall system for you. It will be money well spent. These professionals will have experience or know where and who to consult with for a proper wall design. I should know, I am one.

EIFS is not my favorite material but it does have cost benefits.

Originally Posted by mach2

Last get an Architect or Engineer to design the wall system for you. It will be money well spent. These professionals will have experience or know where and who to consult with for a proper wall design. I should know, I am one.

so being a pro would you mind giving your opinion on the following proposed construction technique for a single story residential?

2" 2.5lb. T&G XPS glued and fastened directly to 2x6 studs.
also glued/sealed at the T&G.
heavier than standard glass mesh and base coat with dryvit style finish coat.
no sheathing.
interior is unfaced fiberglass and 5/8" drywall.

climate: hot as hell, AC is used for 8 month out of the year, maybe a bit of heat is used for a month or so during the winter, 45-50F is probably the coldest it ever gets. rains only during the winter, somewhere around 16 inches.

Since the OP originally mentioned EIFS in reference to an insulating role, with an R-19 rating being the goal, suffice it to say that no exterior cladding system, be it wood, vinyl, masonry, stucco, fiber cement board, or metal, can provide more than a limited portion of the building envelope's total R-rating. Accordingly, the type of construction used in the new addition would be an important consideration in determining how the R-19 goal is to be met.

The past history of EIFS problems has been chronicled endlessly, and often sensationally, in tens of thousands of reports ranging from the sublime to the ridiculous. And without a doubt there were plenty of problems, many due to shoddy installation, but also others owing to poor component performance, unsuitable design, and inappropriate requirements by local building officials.

That was then, this is now, and there a number of the newer drainage managed synthetic exterior finishing systems available that, appropriately spec'd and properly installed, can be viable choices for an exterior cladding. My recommendation would be to seek the advice of a well-referenced design professional with specific experience in exterior cladding systems in you locale.

Several respondents have mentioned moisture control measures, including “vapor barriers”. Moisture vapor in structures is one of the most misunderstood, confusing, and passionately argued issues in the modern building world, as evidenced by an array of opinions already offered on this thread. Here's a link to an excellent paper that may help in understanding the science and complexity of that subject:

BSD-106: Understanding Vapor Barriers — Building Science Information

~TW~

No, I would not do that over the internet and not without a contract that spelled out what my responsibilities were to be. At the same time you should not be building a building without contracts either. I will say this:

Dryvit is one of the more reputable manufacturers and one I have used in the past.

Use only sheathing and installations as recommended by the specific EIFS manufacturer you are using. Make sure that in your agreements the installer be certified by the manufacturer of the EIFS being used and that all manufactures requirements are being followed. Don’t permit mixing of EIFS products of different brands. If there is a problem each will blame the other.

Glass mesh is a good reinforcing material but needs to be evaluated based on the expected use or abuse. If you are unfamiliar with durability of the EIFS ask the manufacture to show you a sample, and then test it. Sounds simple but that’s what we often do when considering a product new to us. If the manufacture won’t do that then look for another…. and tell them why.

Fiberglass in insulation is fairly consistent but fiberglass products come in many forms, the same for drywall. These products will be part of a wall system and should be selected as such. You did not mention a vapor barrier. Placement of vapor barriers within the wall system should be designed to prevent condensation within the wall. Your climate sounds in the southwest. Is the vapor barrier in your case part of the EIFS?

In any case you really need your architect or engineer to have experience directly related to your area and climate. Oh….. and get everything in writing.

Originally Posted by ZAGNUT

so being a pro would you mind giving your opinion on the following proposed construction technique for a single story residential?

2" 2.5lb. T&G XPS glued and fastened directly to 2x6 studs.
also glued/sealed at the T&G.
heavier than standard glass mesh and base coat with dryvit style finish coat.
no sheathing.
interior is unfaced fiberglass and 5/8" drywall.

climate: hot as hell, AC is used for 8 month out of the year, maybe a bit of heat is used for a month or so during the winter, 45-50F is probably the coldest it ever gets. rains only during the winter, somewhere around 16 inches.

Originally Posted by JB @ C and L Machine

We are in the process of adding on to the shop ( pics to come of this project to come ) the new addition needs to meet an R 19 value. The term EFIS is suggested for the addition and existing cinder block building. I have read pros and cons about EFIS, is there another product to achieve the R 19 ?

Run, run away.....

Originally Posted by mach2

No, I would not do that over the internet and not without a contract that spelled out what my responsibilities were to be. At the same time you should not be building a building without contracts either. I will say this:

Dryvit is one of the more reputable manufacturers and one I have used in the past.

Use only sheathing and installations as recommended by the specific EIFS manufacturer you are using. Make sure that in your agreements the installer be certified by the manufacturer of the EIFS being used and that all manufactures requirements are being followed. Don’t permit mixing of EIFS products of different brands. If there is a problem each will blame the other.

Glass mesh is a good reinforcing material but needs to be evaluated based on the expected use or abuse. If you are unfamiliar with durability of the EIFS ask the manufacture to show you a sample, and then test it. Sounds simple but that’s what we often do when considering a product new to us. If the manufacture won’t do that then look for another…. and tell them why.

Fiberglass in insulation is fairly consistent but fiberglass products come in many forms, the same for drywall. These products will be part of a wall system and should be selected as such. You did not mention a vapor barrier. Placement of vapor barriers within the wall system should be designed to prevent condensation within the wall. Your climate sounds in the southwest. Is the vapor barrier in your case part of the EIFS?

In any case you really need your architect or engineer to have experience directly related to your area and climate. Oh….. and get everything in writing.

i'm not asking for you to sign off on the process, just want to know what you think of it...your opinion. i'm half way around the world so i won't be dragging you into court...

the XPS, base and finish coats have been designed to work with each other and the manufacturer has given us their blessing with the caveat that over an open frame it will be more susceptible to damage and they wouldn't go over 20" stud spacing. the frame is where we're having disagreements between our engineers. those more familiar with american style stick framing have no problem with the open frame as long as bracing is up to snuff. others are calling for everything from regular old 1/2" OSB sheathing all the way to cement board over metal studs.

me? i like the open frame idea best. IMO, if (and when) moisture does breach the finishing system it'll be in the relatively breathable wall cavity and there is less chance for it to do any damage. of course labor and material costs also play a part....