Retrofit: Basement Foundation Wall Insulation Choices

Basement block foundation wall insulation

I have been auditing & retrofitting homes as an additional service to my remodeling company for 3 years now. My all-star insulator sadly passed away recently and I am just getting started with a new provider.

This new provider has specified Polypropylene Scrim Kraft to insulate unfinished basement block walls:
http://www.jm.com/insulation/building_insulation/products/bic447_ba...  

Thus far, I have used Thermax on my projects: 2" foil faced poly-iso taped at ALL seams. He indicated that the PSK (Polypropylene Scrim Kraft) is cheaper, also satisfies the code for fire, and has a white finish which looks better. The JM product is formaldehyde free.

The 2 products have very close thermal values and I suspect will perform similarly when taped at seams and installed continuously.

My concern is moisture and durability. We know that moisture moves through block walls. This home does not have active bulk water infiltration issues, but I am still hesitant to use a fiberglass product against a masonry wall.

 

What do you use? How do you install it?

I look forward to your input.

Thanks in advance.

Views: 1258

Reply to This

Replies to This Discussion

I am going to be upfront and say this is one application of our insulating coating that I have not performed myself.

 

Our distributor in Texas has painted / coated basements and foundation walls for many years.  All of his referrals are by word of mouth and he has never bothered to gather data, statements or pictures, at least none that he can find on his computer.  If you go to our site, at the top is his name and Cell number, Joe Merrell.

 

Give Joe a call and he can tell you all about the jobs, results, cost, etc.  He has had excellent results spraying the block walls, A/C and heatibg ducts and under the floors of houses.

 

Oh yeah, we are rated at 4.93 US Perms and are a Class A Type 1 Fire Retardant

 

http://www.ct-texas.com

 

 

I have no experience with Polypropylene Scrim Kraft.  However, we all know that Thermax does a great job and that wet fiberglass is a huge problem.  I can't see how fiberglass on a basement wall would be anything other than a huge headache.  I surely wouldn't switch without a multiple house third party study that showed Polypropylene Scrim Kraft effective.

I am really suspicious when I read on their site that Polypropylene Scrim Kraft Non-Perforated (according to site, resists water vapor transmission) is recommended for most basement walls.  We have known for years that nothing should be put on basement walls (that are below grade) that resists water vapor transmission.  Below grade walls can only dry to the inside. Any vapor barrier would trap moisture inside the walls leading to possible mold and rot problems.

Until our local building code converted to 2009 IEEC this stuff was used by a number of builders in this area.  I bought a house with it draped on the basement walls.  Removed draped insulation package and installed 2" foam to concrete, sealed seams and framed and rocked interior so we could use basement.  The draped material did not fully cover wall, had gaps, tape seams were open,  and in no way did a reasonable job of insulating the basement walls.  It was just the cheapest way to meet the code - again proving a house built to code is the worst possible house you can buy!

Applied to concrete basement walls with rollers and brushes.  Cerama-Tech's perm rating is 4.93 US Perms.  Never had a moistrue problem reported and has solved many mold problems.

 

http://www.ct-texas.com

I would like to offer my two cents and say it is always preferable to insulate on the outside so the foundation stays warm instead of the inside where the foundation is cold and runs the risk of condensation if air by-passes the interior insulation.  It is often difficult to insulate on the inside unless the basement is tottaly clear of items.

RSS

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.

Latest Activity

Richard Vito joined Sean Lintow Sr's group
Thumbnail

Best Practices (Residential)

Best Building, Retrofitting, or even Auditing Practices - what are they, what should change, what…See More
7 hours ago
Richard Vito joined James Sayers's group
Thumbnail

Marketing Energy Efficiency

Sharing ideas, tools and examples of promoting energy efficiency to consumersSee More
7 hours ago
Richard Vito joined Allison A. Bailes III's group
Thumbnail

HVAC

HVAC design, Manuals J, S, T, & D, Duct leakage, Air flow, ENERGY STAR new home requirements,…See More
7 hours ago
Richard Vito joined Kyle Brown's group
Thumbnail

Wrightsoft - Manual J / Manual D

If you use Wrightsoft to calculate loads or design ducts, you likely have questions.  Get answers…See More
7 hours ago
Richard Vito joined allen p tanner's group
Thumbnail

Energy Auditing Equipment for Sale, Trade or to Purchase

Discuss the pros and cons of the equipment you are interested in prior to purchase. Post equipment…See More
7 hours ago
Jim Gunshinan commented on Jim Gunshinan's blog post Energy Upgrade California—Up Close and Personal
"I had a revelation while attending Bruce Manclark's session of duct leak testing at the Energy…"
22 hours ago
George J. Nesbitt commented on Jim Gunshinan's blog post Energy Upgrade California—Up Close and Personal
"Blower Door; the 2007 test was a depressurization test, and the 2014 a pressurization test, which…"
22 hours ago
George J. Nesbitt replied to Kaushal Bharath Raju's discussion Affordability & Deep Energy Upgrade/Passive House Retrofit in Berkeley, California.
"Plan, plan, plan, plan. The 1st step to is to understand the house, how it's built, the…"
22 hours ago
George J. Nesbitt posted an event

High Performance Windows - A Panel of Experts at Pyramid Alehouse`

April 26, 2014 from 3pm to 5pm
Join a lively panel discussion on high performance windows. We'll cover some basics, as well as…See More
23 hours ago
Kaushal Bharath Raju replied to Kaushal Bharath Raju's discussion Affordability & Deep Energy Upgrade/Passive House Retrofit in Berkeley, California.
"Hi David, Thanks for pointing out Martin Holiday's article. I do not wish to engage in the…"
yesterday
Profile IconAdam Penberthy, Scot Davidson and j jarvella joined Home Energy Pros
yesterday
David Eakin replied to Kaushal Bharath Raju's discussion Affordability & Deep Energy Upgrade/Passive House Retrofit in Berkeley, California.
"More food for thought on this subject - read this (fairly) recent blog by one of the most respected…"
yesterday

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service