Today we continue with case No. 913, involving Alison Shiver, and her husband M.E. Timbers.
To recapitulate, the ‘Shiver me Timbers’ people are dealing with the fact their roof is producing more ice, in the form of icicles, than the 10 commercial freezers working 24 hours a day at their ice cube company.
The problem? A home attic space that’s too warm, due somewhat in part to heat infiltrating into the attic space, and largely in part to an under-insulated attic floor.
Step one to remedying the infiltration issue involves sealing the gaps found where the electrical outlet’s octagon boxes, and venting ductwork, penetrate the ceiling’s drywall. Products that would serve well in filling these gaps would include an ‘acoustic seal’ caulking, or ‘Gaps n’ Cracks’ spray foam.
Next, we need to ensure any exhaust ductwork traveling through the attic space is not emitting heat. Often, bathroom fan ductwork is fed through the attic, then exhausted out the soffit, or worse, left lying on the attic floor, feeding warm air into what’s supposed to be a cold environment.
One, ductwork travelling through a cold space, such as your attic, needs to be insulated. This can be accomplished by either by wrapping what’s existing with fiberglass insulation and a six-millimeter plastic, or replacing the ductwork with the insulated version of whatever flexible pipe is needed.
Next, we make sure this duct vents out a gable wall, or better yet, out the roof. Because the soffit acts as intake ventilation, the feeding of warm, moisture-filled air created by showers and baths into this area is counterproductive.
Maxi-vents located at the peak of the roof work in conjunction with the soffit vents to create a draft.
Essentially, feeding your bathroom exhaust into the soffit will only have it re-entering the attic space. Venting out a gable wall, or the roof, ensures this humidity gets lost in the atmosphere.
Next, remove those dated pot lights and replace them with the significantly more efficient, non-heat producing, LED-recessed lighting. Pot lights are notorious for their inefficiency, the fact they create heat, and their habit of allowing warm air to infiltrate the attic space.
So, make the change to LED. Fitting tight to the ceiling, and being a fraction of the thickness of a pot light, the newer LED fixtures don’t protrude into the attic space, and therefore will require no special protective cover over top, making them an easy, value-added renovation decision.
Then, we insulate. Because heat rises, and cool air sinks, there’s a big benefit to adding insulation to the floor of your attic. Basically, insulation slows down the transfer of heat, or the transfer of cold, from one space to another.
The more insulation or R-factor that you have in your attic, the longer your living space below will stay warm, which will result in lower fuel costs.
The new home standard for attic insulation is R-60. In order to achieve this level of thermal value, a homeowner would need to cover their attic floor with about 18 inches of fiberglass pink insulation, or about 22 inches of Atticat blowing wool.
Most homes have at least six-to-eight inches, or about R-20 of insulating value in their attics already.
So, you’re basically needing to top things off to our 2018 standards.
Fiberglass pink comes in batt form, whereby a standard attic “batt” is 24 inches wide, by 48 inches long, by the desired thickness. Choosing the batt strategy will require the homeowner (or hired hand) placing each piece individually across the attic floor. If this is to be your preferred method, choose the R-20, six-inch thick fiberglass pink batt. This thickness of batt handles easy, and gets you to your R-60 goal quite effectively by using a crisscross pattern of laying the second series of batts over the first.
In Alison and Mike’s case, we’re going to be choosing the Atticat blowing wool. Next week, we find out why.