Category Archives: Insulation

Insulation Part 3 – Sound Attenuation (and Amplification)

The final stage of insulation to go in was cellulose between interior floors and walls. The purpose of this insulation is different than in the previous two posts. This time we’re insulating for sound between floors and rooms.

Anyone who’s stayed at our house becomes quickly aware of the sonic transparency of the space. First floor? Second floor? Bedroom? Bathroom? It doesn’t really matter where you are – it’s like everyone’s in the same room together. The complete absence of a subfloor on the second floor was the primary culprit, and this, combined with ill-fitting passage doors, likely caused most of the problem. But, as long as we were insulating before drywall is put up, we figured we may as well do everything we can to attenuate sound, as well.

We’re also covering the exact opposite goal in this post – sound amplification. As you’ll see in the photos below, one final infrastructure element that was never covered in the recent posts on this topic went in immediately before insulation began. This was the AV infrastructure, including speakers in the ceilings. To make the schedule and install before insulation, our AV consultants sent a double crew over on a Monday morning to string Cat 5e network cables and speaker wires all over the house. Insulation began promptly on Tuesday morning.

The sound insulation Tuesday evening was a sea of moss green flowing across the first floor ceiling. Here’s a view north, from the kitchen. In addition  to the recessed light fixtures, you also can see one of the two, 4″-diameter kitchen speaker placements in the center.

Heres’s a view west, to the wet bar and pantry wall:

The powder room also got the full treatment, for obvious reasons. No longer fear chili night at Wolfe Street!

In addition to the cellulose insulation, solid panel insulation has been applied to both sides of the pocket for the pocket door:

In addition to the insulation, this picture also shows the center and left speaker locations for the surround system. It’s a 5.1 system, so three of the 6″-diameter speakers are in the bay where that center speaker is located and the left and right satellite speakers are on the back wall. The subwoofer will be located inside a cabinet under the dining/kitchen peninsula.

The photo above also shows the TV niche, which has been framed out. The AV guys at this point have run network cable and HDMI cables to this location, which is what’s hanging out there.

All of the network and audio cables in the house (kitchen, living room, and the two bedrooms and bathrooms upstairs) make “home runs” down to an equipment hub in the basement. We’ll have shelving here, and the utility sink is being moved south.

Heres’s another view of the coils of cable awaiting connection much later in the project.

Upstairs, all of the bathroom walls got the same treatment. Here’s the shared wall between the two from the master bathroom side:

Insulation between the master bath and walk-in closet:

This is what the wall between the guest bedroom and guest bathroom looks like before drywall is installed. You craving burritos while staying at Wolfe Street? Interested in more cabbage than corned beef when coming to stay for the annual St. Patrick’s day party? No problem; go crazy!


Posted by on May 20, 2012 in AV, Insulation


Insulation Part 2 – Batting

The day after foam insulation was adhered to the insides of the horizontal exterior spaces, the sub was back to install batt insulation between vertical framing members at the back of the house.

Here’s the kitchen after this stage:

Looking southeast to the wet bar and pantry area (you can also see the isynine insulation at the joist ends in this shot):

Master bedroom looking east:

And looking west (I’m sure it’s incredibly exciting see not one, but both views . . .):

The final stage – cellulose insulation for sound attenuation – is next.

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Posted by on May 19, 2012 in Insulation


Insulation Part 1 – Foamy Goodness

After framing went up at the back of the house and house infrastructure elements were installed, insulation activities began. As indicated in posts during the demolition stage, our old house had absolutely no insulation. Seriously:

With the renovation, we’re properly insulating all of the exterior walls that are framed. We can’t do anything about the front of the house or the eastern wall north of the framed area, since these walls are solid brick. The west side is a party wall, so no need to insulate there.

We’re installing three types of insulation:

  1. Isynine (foam) insulation below the roof deck, at the joist ends, and below the kitchen door overhang. Foam insulation’s got the best insulation qualities, but is also several times the cost of batting, so we use this on the most critical areas.
  2. Batting insulation between the studs on the vertical walls on the first and second floors
  3. Cellulose insulation in the ceiling joists between the first and second floors and between framing on several interior walls. This has nothing to do with insulation against the weather and everything to do about sound attenuation.

This post shows the aftermath of isynine insulation application.

The insulation sub did a great job. Below shows the foam insulation in the roof deck over the master bedroom looking southwest. The roof is directly above the rafters at the south of the house due to the roof slope, so the foam will occupy the entire area between the drywall that will be installed on the ceiling and the roof):

Looking east:

As we look north on the second floor, the foam begins to adhere to the roof above the rafters, since the roof deck is sloping up.

Insulation around the stairwell skylight:

And, in the guest bedroom, looking west, where it has completely covered the in-line fan units described in this post, as well as the accompanying video:

And looking east:

We’ve also installed foam insulation in the joists below the overhang in back that was created by the master bedroom bumpout:

Next up: batt insulation installation blog publication.


Posted by on May 19, 2012 in Insulation