Northwood News ♦ February 2008

The Continuing Insulation Story

By Jacquie Bokow

In the last issue of the Northwood News, I invited homeowners in the neighborhood to contact me about getting Air-Krete insulation in our homes.  Twelve responded.  Of the 13 total, seven are from the brick cooperative houses on Cavalier Drive and Belton Road and six from other parts of the neighborhood.

Doug Palmer of Palmer Industries came to my house on January 11.  I invited all the folks who had expressed interest to hear what he had to say; since it was during the day, only six were able to attend.  Let me tell you what he told us.

He spoke about the Air-Krete process and, with my house in particular, the difficulties in using it.  My house has “brick on block” construction.  What this means is that there’s a four-inch layer of brick on the outside, directly abutting a four-inch inner layer of concrete block.  Every eight rows the bricks were turned on edge, crossing over the concrete layer.  This looks very pretty outside, and creates a sturdy home, but makes it impossible to enter from the outside through the mortar.  (Workers would have to drill through both the mortar between the bricks and then the concrete block, and wouldn’t know what they would find once they did, i.e., they might be hitting a stud, etc.)  Too, this type of construction means there wouldn’t be a continuous vertical space between the studs in which to inject the Air-Krete.

Also, with this type of construction, there’s only about an inch of space (sometimes less) between the concrete block and the inside drywall and there are usually cross braces horizontally placed, causing further obstruction.  The Air-Krete mixture can still be installed, but it has to be done from inside the house.  This would require at least four one-inch holes vertically up the wall to get into each space; these holes would be cut every 16” (between studs) around the perimeter of the house.

Working from the inside, of course, means bathroom wall tiles and kitchen cabinets create additional barriers.  Mr. Palmer was frank with us:  everything would have to be moved away from the outside walls and drilling the holes makes a real mess, with dirt and dust coming from the holes.  Obviously, they take precautions to minimize the mess; their method is to place an adhesive plastic strip several feet wide on the floor around the inside perimeter of the home.  Additionally, they need to get their truck close enough to the house to reach all the walls and they need access to a water hose.

Each inch of Air-Krete has an R-value of 3.9, so that’s the most we’d be adding to our home.  The product has a lot of wonderful qualities — like being nontoxic, fireproof, a sound barrier, and bugs and mice don’t like it — but it won’t add a huge barrier to the cold and heat outside.  I don’t know what would, though, given the quirkiness of my house!

The job for my house would take two to three days.  The first day, all of the holes are cut.  The second day, the injection of the Air-Krete begins.  The workers use electrician’s tape to probe the area behind each hole they cut, which is why it takes an entire day just to cut the holes.  After the Air-Krete is installed, each of the holes is plugged with a styofoam plug, which would have to be patched before painting, a service they do not provide.

The upheaval would be great, if short in duration.  Our queen-size bed barely fits in our small master bedroom; it would have to be dismantled to give them clearance to get at the wall.  Fortunately, we had our bathroom remodeled four years ago and had pieces of foam insulation placed in the cavity, so we don’t need to have the Air-Krete there, saving the existing tiles.  Others considering the process would have to remove tiles.

We have built-in bookcases covering one outside wall of our living room; hundreds of books and CDs would have to be removed — along with the shelves — before the workers arrived.  In the kitchen, holes would have to be drilled through the cabinets that are against the outside wall; each would have to be emptied first, of course.

Mr. Palmer gave us a quotation of $2,940.  Ours is one of the smallest of the cooperative homes, so I suspect others will cost more.  A neighbor on my block was quoted $3,300.  No group discount was offered, although I sent an email asking Mr. Palmer if he would offer this if enough of us sign up.  Others interested will need to get a individualized bid for their own houses, as each is different.

My husband and I have still decided it would be worth it and plan to have it done in the spring.  I intend to keep everyone posted on the process and whether we notice any difference in our heating/cooling bills afterward.  So stay tuned!   ■

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