Comments on: The One Thing I’d Love to See Building Enclosure Workers Do

By: William Powers

William Powers — Fri, 13 Nov 2015 18:42:56 +0000

Thanks for all your great
Thanks for all your great information, including links to earlier posts.
In reading this blog and your link to an older one on the astonishing heat loss from the uninsulated 1% of attic surface that pull-down attic stairs provide.
Perhaps even bigger black hole for heat loss that I see when doing environmental inspections of homes here in the Northeast is whole house fans mounted in ceilings. Most are not even functioning, so they are not used for cooling the house in the summer as originally designed. (Let’s not even go into the whole topic of the negative air pressure effect in the home running a fan and subsequently drawing who-know-what-kind of make-upair into the structure.)
These fans are obviously made out of metal- sheet metal louvres, metal struts holding up metal fan motors which have metal fan blades. If you wanted to design a radiator to efficiently move heat from the living space of the home to the attic space above, you would have a hard time designing a better one than these.
Of course, these could be covered with tons of insulation, but the money to remove them, patch and paint the ceiling would probably be returned in one heating season!
Besides the energy loss (not my company’s specific reason for being in the home), the movement of heat and humidity to an attic space which then comes into contact with cold roof sheathing and framing in the winter season easily results in condensation sufficient to cause fungal (mold) activity on attic surfaces.
There you have it- whole house attic fans are giant energy black holes AND an insidious way of ensuring that you have mold growing in your attic!

By: William Powers

William Powers — Fri, 13 Nov 2015 13:42:56 +0000

By: Ron Keeney

Ron Keeney — Fri, 13 Feb 2015 01:52:47 +0000

“The house is very
“The house is very drafty and room temps inconsistent”…. that does NOT sound like an insulation problem (or fix) to me. Have you looked hard at the windows? Their quality and installation? Our 30-yr-old had dble-pane “thermal windows” — but the wood sashes fit so poorly that one could hear the wind blowing through the cracks. The basic wood windows were so cheap that many jamb-to-sash connections were literally just wood to wood, with no weatherstripping at all. As a cheap initial fix, we had storm windows installed over the outside of each window (also giving us good screens!).
Now our biggest problem is that the storm windows are tighter than the wood frame “insulated” windows, so the house humidity leaks around the wood jambs and fogs up the storm windows….
As a suggestion, get a couple of the cheap plastic sheet “temporary interior storm windows” — really just a clear plastic sheet taped over the interior window trim. You’ll be able to tell if the plastic is billowing from leakage when windy, if it cuts down on the drafts, and what happens to the interior humidity (where it condenses) — all which may point you at window work, rather than more attic insulation.

By: Ron Keeney

Ron Keeney — Thu, 12 Feb 2015 20:52:47 +0000

"The house is very
"The house is very drafty and room temps inconsistent"…. that does NOT sound like an insulation problem (or fix) to me. Have you looked hard at the windows? Their quality and installation? Our 30-yr-old had dble-pane "thermal windows" — but the wood sashes fit so poorly that one could hear the wind blowing through the cracks. The basic wood windows were so cheap that many jamb-to-sash connections were literally just wood to wood, with no weatherstripping at all. As a cheap initial fix, we had storm windows installed over the outside of each window (also giving us good screens!).
Now our biggest problem is that the storm windows are tighter than the wood frame "insulated" windows, so the house humidity leaks around the wood jambs and fogs up the storm windows….
As a suggestion, get a couple of the cheap plastic sheet "temporary interior storm windows" — really just a clear plastic sheet taped over the interior window trim. You’ll be able to tell if the plastic is billowing from leakage when windy, if it cuts down on the drafts, and what happens to the interior humidity (where it condenses) — all which may point you at window work, rather than more attic insulation.

By: Nancy

Nancy — Thu, 12 Feb 2015 20:06:20 +0000

We live in a 1950's brick
We live in a 1950's brick ranch in Detroit area of Michigan. We have added on a bedroom and family room which have insulated ceilings during new construction. The old part of the house has some blown in insulation. Our furnace and ductwork was moved to the attic after additions were built on. The house is very drafty and room temps inconsistent. We just had crawl space encapsulated by FSM. We have many roof vents and I don't think our attic gets much above 100 deg. in hot summer. Do we add insulation to floor of attic or have blown insulation put under roof rafters? This space will never be "lived in". We do not use it for storage. Thank you for your help in this matter.

By: Nancy

Nancy — Thu, 12 Feb 2015 15:06:20 +0000

By: Ron Keeney

Ron Keeney — Tue, 10 Feb 2015 00:56:20 +0000

Re “One Thing Builders
Re “One Thing Builders Should Do”, I noticed a key phrase at the beginning that “rang a bell” because I too encountered it when I bought a THIRTY-YEAR-OLD HOUSE. What type of insulation are we looking at in your photo? I’ll offer odds that it was blown-in rock wall — THE insulation of the late ’70s and early ’80s. It worked well — AS LONG AS IT WAS SUPPORTED from underneath. Whose responsibility is it to go back AFTER the HVAC sub and “repair” the insulation support around his newly installed duct chase? In my own home, built in mid-80s, and purchased by us in 1990, the previous owners’ comment was “the house was always cold”. Upon thorough inspection of the attic, we found two major overlooked flaws: First, there was NO SUPPORT for the rock-wool insulation around the top of the duct chase “chimneys” and I could have taken pictures nearly identical to that shown. But the proof of the failure was that two stories below, at the bottom of the framed chase, was about an inch of loose rock wool, that had fallen out of the attic opening at the top of chase… all the way to the bottom — absolutely useless. To fix it, we cut 1/4″ hardware cloth to fit around the duct and outward to proper framing support…. and 20 years later, that loose insulation is still in place. Incidentally, one of those two “chimneys” down into the core of the house happened to be the wall that they installed the thermostat on… 15′ below the attic space.
The second discovered flaw was that they had installed a plywood cat-walk down the middle of the attic the whole length of the house. AND THEN the insulation contractor came in and spray loose fill insulation over the entire attic…. (Ever tried to spray that type of material into a 5-1/2″ horizontal space between trusses when already covered with plywood? Yep — absolutely no insulation — in a 4′ wide band the full width of the attic, just drywall, a trapped air space and a layer of 1/2″ plywood.
I estimate that solving those two flaws alone probably cut the heat loss of the house by 50%… and it probably looked real good right after it was done!
(We also then added 6″ of fiberglass, in 20′ rolled batts, perpendicular to the truss cords, over top of the whole attic.)
In my opinion, those simple actions, done by the homeowner long after construction, probably cut the heat loss by 70%.

By: Ron Keeney

Ron Keeney — Mon, 09 Feb 2015 19:56:20 +0000

Re "One Thing Builders
Re "One Thing Builders Should Do", I noticed a key phrase at the beginning that "rang a bell" because I too encountered it when I bought a THIRTY-YEAR-OLD HOUSE. What type of insulation are we looking at in your photo? I’ll offer odds that it was blown-in rock wall — THE insulation of the late ’70s and early ’80s. It worked well — AS LONG AS IT WAS SUPPORTED from underneath. Whose responsibility is it to go back AFTER the HVAC sub and "repair" the insulation support around his newly installed duct chase? In my own home, built in mid-80s, and purchased by us in 1990, the previous owners’ comment was "the house was always cold". Upon thorough inspection of the attic, we found two major overlooked flaws: First, there was NO SUPPORT for the rock-wool insulation around the top of the duct chase "chimneys" and I could have taken pictures nearly identical to that shown. But the proof of the failure was that two stories below, at the bottom of the framed chase, was about an inch of loose rock wool, that had fallen out of the attic opening at the top of chase… all the way to the bottom — absolutely useless. To fix it, we cut 1/4" hardware cloth to fit around the duct and outward to proper framing support…. and 20 years later, that loose insulation is still in place. Incidentally, one of those two "chimneys" down into the core of the house happened to be the wall that they installed the thermostat on… 15′ below the attic space.
The second discovered flaw was that they had installed a plywood cat-walk down the middle of the attic the whole length of the house. AND THEN the insulation contractor came in and spray loose fill insulation over the entire attic…. (Ever tried to spray that type of material into a 5-1/2" horizontal space between trusses when already covered with plywood? Yep — absolutely no insulation — in a 4′ wide band the full width of the attic, just drywall, a trapped air space and a layer of 1/2" plywood.
I estimate that solving those two flaws alone probably cut the heat loss of the house by 50%… and it probably looked real good right after it was done!
(We also then added 6" of fiberglass, in 20′ rolled batts, perpendicular to the truss cords, over top of the whole attic.)
In my opinion, those simple actions, done by the homeowner long after construction, probably cut the heat loss by 70%.

By: gennaro ameno

gennaro ameno — Thu, 22 Jan 2015 19:37:38 +0000

Building Enclosure Heat Loss
Building Enclosure Heat Loss - A wall section thru many brick veneer multistory structures is the best example of heat loss at a building enclosure in my opinion. The perimeter steel beam and brick support angle are usually shown with loosely placed insulation at the web of the supporting beam. A infrared photo of our building shows a continuous band between each floor and ceiling space resulting in cold floors. Is there any remedy?

By: gennaro ameno

gennaro ameno — Thu, 22 Jan 2015 14:37:38 +0000