Attic Trusses – Room Size

10 responses

  1. Heather
    May 18, 2012


    My husband and I are embarking on a new build/renovation to an existing 24' by 36' story and a half cape cod with knee walls. We are planning on our addition to be 24' wide by 26' in length, to add a larger living room in the main floor and an extra bedroom and bathroom in the top floor. My question is; How do you calculate what the actual "living space' will be for the top-floor area? We are going to be building storage space into the kneewall part, but are having a heck of a time figuring out the top-floor area for bedroom/bathroom sizing. Any suggestions or help would be greatly appreciated...Many thanks, Heather

    • Tim Carter
      May 23, 2012


      I developed this product just for questions like this. Way too involved to type and would take far too much time. I'm sure you understand the value of time! Take a look at my 15-Minute Phone Consult.

  2. carol turley
    November 7, 2012

    i need help designing an attic room on new construction. house will be 60 feet long by 28 feet wide. I need to knoww what size the room will be at what pitch roof

    • Tim Carter
      January 6, 2013

      Carol, your question requires lots of typing, plus I have some questions for you so I can give you the correct answer(s). I only do pithy answers here in the comment section. If you want to protect the investment you have in your house and not waste time or money *hoping* you make the right decision, you should talk to me on the phone for just 15 minutes. It'll be the best investment you've ever made in your home!

      • paul
        June 10, 2013

        I just installed 28' wide attic trusses over my garage, and the attic room was 15'-11" with 5' knee walls and 8' ceiling at the center. roof pitch was 12/12. hope this helps.

  3. Dan
    December 17, 2014

    Im building a 22 ft wide room do I use 2x4 0r 2x6 trusses Thanks Dan

    • Tim Carter
      December 20, 2014

      2x4s will work just fine for the trusses - assuming you use the right lumber species, connector plates AND the trusses are designed by a registered engineer!

  4. Amanda shaw
    January 20, 2015

    Hi my new house is going to be 50 long by 48 feet wide Are you saying in the first paragraph it would be better to use trusses rather then rafters? I am wondering bc we are having a loft Area in the top of our house going down the middle? Thanks!

    • Tim Carter
      January 20, 2015

      Correct. Those would be massive compound rafters with a house width of 48 feet! You'd have to have two interior bearing walls for regular rafters.

      Using attic trusses, you'll have an ENORMOUS room if you go with a pitch of 8/12 or greater. You'll need a crane and experienced crew to set them!

  5. Dean Hook
    February 26, 2016

    I'm building a garage 24' x 24' and I want to constuct my own Attic Trusses. Using a 10/12 pitch, I plan to use 2 x 10 for joists and 2 x 4 for rafters and web supports. Can I put the trusses on 2' centers? The walls will be constructed of 2 x 6 modern framing on 2' centers.

Leave a Reply


mobile desktop