Walls and insulation

From Green Garage Detroit
Jump to: navigation, search

return to As Built

Windows, walls and floor on historic side of the building

Sustainability goals for our wall system

Because we were designing a Super Insulated Building Envelope, our wall system design was extremely important. Our goals included:

  • Minimize thermal bridging and air infiltration.
  • Reduce energy use of existing building by at least 70%.
  • Use envelope and insulation materials that do not harm building occupants or the environment.
  • Use envelope and insulation materials that are existing, recycled, and/or local materials wherever possible.

Wall design

Historic side

Cross section of historic side wall system.

Built second wall inside the brick/block walls to accommodate super insulation while preserving historic appearance and keep block from entering waste stream. Modeled wall system with WUFI software to determine how best to achieve high R-value and also deal with moisture within our super insulated wall assembly design.

  • Historic brick/block layer 8" thick
    • Weep holes at base of wall to drain moisture from behind masonry layer
  • Drainage plane 1" thick
    • This air layer helps control thermal bridging by separating the inner wall from the outer wall
    • Also helps control moisture build up in the wall by providing a path for condensation or rain water to run down to weep holes
  • Furring blocks 1" thick
    • Controls thermal bridging by holding stud wall away from drainage plane behind masonry
  • Polyiso rigid foam board 2" thick, 2 layers with staggered seams (total of 4" thick)
  • Cellulose blown-in insulation (and 3 1/2" wood studs) 5" thick
    • Absorbs and dissipates moisture like a living organism
    • Contains fire retardant and mold inhibitors
  • Gypsum wallboard 1/2" thick (made from flyash, 100% recycled material)
  • Total thermal resistance for the walls is R-42
  • Total wall thickness is 18.5".

Use of homasote

Homasote (made from 100% recycled newspaper) covers a portion of the walls in the historic side of the building, specifically the upper half of the walls in the meeting rooms. This surface is perfect to tack things up on.

Annex side

Caulking the walls of the annex.

The walls on the annex side were built just like the historic side walls.

  • Historic brick/block layer 8" thick
    • Weep holes at base of wall to drain moisture from behind masonry layer
  • Drainage plane 1" thick
    • This air layer helps control thermal bridging by separating the inner wall from the outer wall
    • Also helps control moisture build up in the wall by providing a path for condensation or rain water to run down to weep holes
  • Furring blocks 1" thick
    • Controls thermal bridging by holding stud wall away from drainage plane behind masonry
  • Polyiso rigid foam board 2" thick, 2 layers with staggered seams (total of 4" thick)
  • Cellulose blown-in insulation (and 3 1/2" wood studs) 5" thick
    • Absorbs and dissipates moisture like a living organism
    • Contains fire retardant and mold inhibitors
  • Gypsum wallboard 1/2" thick (made from flyash, 100% recycled materials)
  • Total thermal resistance for the walls is R-42
  • Total wall thickness is 18.5"



The importance of insulation

Stacks of used polyisoinsulation, in background, filled up the building for months before installation in our walls.

Insulation was the most important element in the energy plan for our building. Some points about our use of insulation include:

  • We purchased once-used polyiso insulation (rigid board) at the Insulation Depot in Massachusetts. They sent it to us in trucks and we stored it in the center of the historic side of the building until we were ready to install it.
  • We used 3 types of insulation in our walls: polyiso, cellulose and spray foam.
  • On the historic side, we installed 16" of insulation (R=100) above the original roof; 81/2" in the walls (R=45); 2" under the floors (R=15).
  • On the annex side, we installed 10" of insulation (R=60) on the top of the original metal roof and 8 1/2" in the walls (R=45).



Resources

  • Insulation specialist
    • Byczynski, Ken (Building Science Consultant)
Kenco Energy Services
kensr.kenco@gmail.com
248-895-8161 - Mobile
7273 Tucker Road
Holly, MI 48442
  • Insulation Supplier
David Volpe
Insulation Depot/ (Used rigid insulation supplier)
508.532.1851

See also