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The Historic Roof

Tom Brennan and Ike Sheppard at the roof inspection. I LIKE IKE!

Before purchasing the building we had it inspected by a structural engineer named Ike Sheppard. Ike determined that although the overall structure was sound, the roof would need to be replaced. We decided that instead of replacing the roof, we would keep the existing roof intact and build a new roof over it. This way, we could save all of that material from ending up in a landfill, with the added plus of keeping the beautiful existing barrel roof and bow trusses. We bought the building in December of 2007 and knew it would be a couple of years before we could put on the new roof, so we made some repairs to the old roof so the building would stay secure and dry.

Roof Design

Historic side

  • Modeled roof system with WUFI software to determine how best to achieve high R-value and also deal with moisture within our super insulated roof assembly design
  • Layers detail
    • Laminated veneer lumber beams (engineered to span truss to truss)
      • Blocked down to original truss through the roof
      • Served 2 purposes:
        • Allowed us to build new roof over existing roof
        • Gave us opportunity to straighten the roof
    • Completed vapor barrier where none was present
    • Multiple layers of polyiosinsulation (staggered seams)
    • Spray foam the joints (limiting air infiltration)
    • Screw down insulation to old roof deck
    • 2 x rafters go up (reused from ceiling that was taken out from our interior)
    • More layers of polyiso added where able
    • Oriented strand board added with gap for cellulose
    • Cellulose blown in under OSB
    • Deck Armor layer added (breatheable roof deck protection)
    • Duro-Last added (white roofing membrane)
  • R = 115
  • Can Joe do another drawing of roof cross-section?

Annex side

  • Layers detail
    • Original roof
    • 9" polyisoinsulation with staggered joints
    • Layer of OSB
    • DoroLast
  • R-65


A look into the construction process for the roof....

For more images of the roof construction, see our Roof construction Flickr Set.


  • Insulation specialist
    • Byczynski, Ken (Building Science Consultant)
Kenco Energy Services
248-895-8161 - Mobile
7273 Tucker Road
Holly, MI 48442
  • Insulation Supplier
David Volpe
Insulation Depot/ (Used rigid insulation supplier)
  • Duralast membrane
  • Solatubes
  • Walnut-shell blasting
    • Ron Wells
    • Grand Northern Products
    • 9000 Byron Commerce, SW
    • Byron Center, MI 49315
    • Phone: (616) 583-5000
    • Toll Free: (800) 968-1811

See also