What One Modern House Tells Us About the Future of Urban Building – Next City

via What One Modern House Tells Us About the Future of Urban Building – Next City.

On a Tuesday morning not long ago, I entered a half-assembled house tucked into a quiet corner of Somerville, Mass. In much of this small city, adjacent to Cambridge, you can no longer walk down the block without passing a yoga studio or an artisanal butcher. But this residential street still felt more like the blue-collar town of a previous generation. Outside, a yellow crane lifted a floor deck high overhead. A few men wearing hard hats and tool belts busied themselves inserting screws and climbing ladders. MORE

Why We Use Dense-Packed Cellulose Insulation

Bensonwood's proprietary OBPlus Wall

A cross-section of Bensonwood’s cellulose-filled OBPlus Wall®.

Many have asked us why we use dense-packed cellulose insulation in our OBPlus Wall® panels, roofs and some ceilings and floors. Here are some of the cellulose advantages in our “Montage Building” system:

  • Our cellulose insulation is made from recycled newspapers treated with a natural mineral borate to give it a Class A fire rating as well as resistance to mold and pests.
  • The dry cellulose is blown into all the framing cavities at a settle-proof density (dense-packed), filling any shape with a continuous thermal insulation layer. The blowing process compresses the cellulose to a density of between 3 and 4 lbs/cu.ft. In addition to preventing any settling of the material, the dense-packed cellulose also cuts down convection that can occur around batt type insulation and in low-density blown fiberglass, particularly in colder temperatures.
ob plus wall with dense packed cellulose

Cellulose being blown into a Bensonwood wall panel.

  • Dense-packed cellulose blocks air movement better than fiberglass batts. While sprayfoam also seals the enclosure against air infiltration well, its rigid consistency when cured may allow it to crack as framing members around the insulation dry and move over time. Cellulose has the flexibility to allow for such movement without resulting gaps.
  • Similar to wood fiber, paper cellulose fiber manages moisture well, taking in and releasing the moisture effectively. As a result, indoor relative humidity is much more even due to the hygroscopic buffering capabilities of the cellulose insulation. This is in contrast to the hydrophobic characteristics of fiberglass and foam insulations, which lack this capability and can cause a home’s interior to experience significant swings in humidity when weather changes. So, with its tremendous insulating and moisture management characteristics, cellulose helps to buffer temperature and humidity extremes.
  • While foam insulation has a slightly higher R-Value per inch, cellulose takes less energy to manufacture than any other insulation material. This embodied energy includes the total energy required to transport the raw materials, then manufacture and distribute the finished product. Fiberglass has up to 10 times more embodied energy than cellulose and foam products have as much as 64 times more.
  • Cellulose insulation is one of the greenest building products, having the highest level of recycled content in the insulation industry—as much as 85%. Fiberglass has a maximum of 40% recycled content and foam products little or none.
  • Cellulose sequesters carbon in a building’s components instead of releasing it into the environment. Cellulose insulation is made from recycled paper that might otherwise end up in landfills, releasing methane as it decomposes, or be burned, releasing CO2. This sequestration results in a positive carbon balance which helps the efforts to lower the material’s impact on climate change.
  • Cellulose insulation is produced regionally, employing local recycling programs and independent recyclers.
  • While all insulation provides sound reduction, cellulose has approximately three times the density of fiberglass as well as fibrous consistency, delivering enhanced sound dampening.

For more details on cellulose insulation, visit http://www.nationalfiber.com/cel-Pak.htm or http://cellulose.org/GreenestInsulation/.

What dense-packed cellulose looks like inside a wall.

What dense-packed cellulose looks like inside a wall.

First Unity Home: Part 1: In the Shop

Our first Unity Home is on-site this week. A five-person team will be raising a Xyla in a just a few days.

In this video (1 of 4 on our YouTube channel) Jay Lepple, Bensonwood’s Building Systems Team Leader demonstrates the features of a wall panel that was recently fabricated in our shop for this home.

This is video 1 of 4, with other videos demonstrating window and siding installation in shop, and the benefits of the Computer Aided Design (CAD) in our off-site construction process.

Walls in the shop

Wall panels packed and ready for wrapping before being trucked to the site