GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter X Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Finding roofer in SE Michigan who is experienced with rigid roof insulation

user-6625223 | Posted in General Questions on

We live in metro Detroit, climate zone 5A, and have a 20 year old roof, original to house and we are original owners.

In about 2008, we spray-foamed the roof deck with open cell foam because we were having issues with condensation in the attic. I think the condensation was caused in part by heat from the front bedroom traveling into the attic via the soffit vent baffles.(see photo for reference)  Attic is now unvented. Have not had any issues with condensation since.

Attic gets very humid in summer on peak heat days. Two years ago, we installed a dehumidifier in the attic to run on humid days. 

It is time to replace the roof and I want to add about 6” of rigid exterior insulation on top of the roof deck. Open to suggestions on which type would be best.

Front section is about 16’ wide  x 20’ deep, back section is 25’ wide x 30’ deep. steep pitch. 

Most importantly, we need to find someone who can install it properly so we get the best end result. This is not common in our area, so how do we find a good contractor for this job if it hasn’t been done here before?

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. Expert Member

    User ...223,

    Adding 6" of exterior insulation involves a lot of work which is outside the ambit of roofers.
    - You will need new, much thicker fascias.
    - The roof will also need a new layer of sheathing secured right through to the rafters.
    - The siding will have to be removed and replaced at the side-walls.
    - The gutters will have to be replaced.

    I would first look for someone to write a Scope of Work and Specifications detailing what is involved. Then find a small General Contractor who can coordinate the work involved, and the sub-trades necessary.

    1. user-6625223 | | #2

      Thanks for the bullet points and pointing me in the right direction Malcolm.

      1. Expert Member
        MALCOLM TAYLOR | | #3

        User ...223,

        It looks like nice house. Good luck with your project.

    2. kiwiscott | | #4

      Who would do this "someone to write a Scope of Work and Specifications detailing what is involved". most architects I talk to aren't interested.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |