I’m not sure what happened, but I haven’t been getting notified of questions on Ted’s Tips for months now. I just thought everybody was happy or nobody was reading!
I think I answered the backlog of questions, but if I missed your question, please submit again, and I’ll get back to you ASAP!
Ted's Energy Tips 
Hi Ted, Thanks for soliciting energy conservation questions. My wife and I are in the midst of restoring a fairly original 130-year-old Victorian house in Port Townsend, Washington. I’m primarily interested in your take on insulating materials for this house, though we are also planning to install a multi-zoned mini-split heat pump and rooftop solar. Our insulation bid includes closed-cell foam applied to the underside of the 12/12 roof, loose-fill fiberglass insulation in the attic floor and dense-packed fiberglass for the balloon framed walls. We are finishing the attic, so foaming the 2″ x 4″ rafters makes sense. The attic floor gets 6″ of loose fill.
The exterior walls are clad with unpainted, vertical grain fir 1″ x 8″ shiplap that’s weathered but quite sound. Some of the original cut nails require resetting. The exterior walls have breathed over the decades and the unfinished attic end walls show no water staining, just dust patterns from air movement. I assume that the other walls are the same. Interior walls are lath and plaster interior with original trims and moldings that are keepers.
We want to insulate the walls without introducing unintended consequences, such as causing moisture issues in the walls.
Our local insulation contractor recommends a fiberglass fill. We’ve used both cellulose and fiberglass on houses we’ve lived in. Do you want to weigh in on your preference?
Cordially,
Jim O
Thanks Jim, I wonder if you knew my friend, Bob Knudson who retired there? Sadly he passed in 2009…
With regards to your renovation questions, I’m curious about the insulation for both the roof underside and the attic floor. That’s typically a no-no as you’re encapsulating an entire area. If you insulate under the roof, then you wouldn’t need to insulate the floor, especially if you’re turning the attic into living space. OTOH, I know sometimes people use insulation as sound absorber.
With the typical weather conditions in PT, it doesn’t appear that you have too much to worry about excess humidity. I was surprised to see how little rain you get there. What a great climate you have! With moderate temperatures and not-excessive rain, you shouldn’t have to take extreme measures to minimize the chance of moisture problems. People in my area use dense-packed cellulose in construction like yours without problem, as long as they’re not filling a space behind a brick/stone wall, which needs an airspace to flush out humidity. But with typical construction, it should be ok. But double-check with your insulator and request references for other clients of theirs who have similar construction in your area. There’s a wide range of quality of dense-packed cellulose insulation jobs, so getting a quality installation is critical.
Most “green builders” prefer cellulose over fiberglass, especially dense packed. The dense pack cellulose is vastly better at stopping unwanted air movement. It also buffers moisture, which can be good or bad. It’s good because, like a sponge, moisture that gets in, absorbs and spreads throughout, then releases it over time. This helps to reduce the risk of moisture buildup in one spot. On the other hand, if there’s a leak, it can soak in lots of water and hold it. So you don’t want leaks!
Here’s a nice article on dense packing walls by the master of Building Science
I have not gotten any updates on Ted tips either for many months this is the first one I have gotten.