GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter 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

40 inch insulated exterior door

user-6798160 | Posted in Green Products and Materials on

I’m working with a builder to get an exterior door for a walkout basement. I’d like to get an insulated fiberglass ThermaTru, but it seems that they only have 3′ wide doors. Does anyone know where I can get a standard 40″ door (with a single small lite) in fiberglass? I know that I can get custom passiv Haus doors for 8k$ and up, but that seems excessive. I’d prefer not to get a solid wood door, but I may end up backed into that option if I can’t find an EnergyStar door.

Thanks so much to everyone in advance.

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
    BILL WICHERS | | #1

    Have you tried a commercial door distributor? 40” is an oddball size, but probably out there, maybe for wheelchair accessible places. I’ve ordered plenty of 8 foot high doors, but when I’ve needed wider I always go with a double door. I’ve never ordered a single door over 36” wide.


  2. Expert Member
    Michael Maines | | #2

    Kathryn, Therma Tru will do 42" wide door slabs but only in full-light, and not with their sleek flush glazing detail. Could you work with that?

    I recently installed a 42" full light, double-glazed, wood-framed door from Simpson. Not particularly energy efficient but the glass performs better than solid wood, and the price was reasonable compared to custom doors.

  3. user-6798160 | | #3

    Conclusion :
    I ended up just getting a solid wood door. Maybe for the next renovation, I'll change the size of the door frame, but in this instance it just wasn't worth the trouble.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |