Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Depth of Truss Joists

  • 03-02-2014 9:20pm
    #1
    BarneyMc
    Registered Users, Registered Users 2 Posts: 1,504 ✭✭✭


    I'll be ordering my trusses soon and have nailed it down to 2 suppliers.

    One provides 4 inch deep joists and 6 inch whereas the other provides 8 inch. Am I right in saying the 8 inch would have the advantage of allowing a thicker roll of insulation before I cross it over with another layer and therefore the best option in this regard? If using blown in cellulose then I assume it wouldn't matter?

    It will be a cold attic by the way.


Comments

  • #2
    BryanF
    Moderators, Home & Garden Moderators Posts: 10,146 Mod ✭✭✭✭BryanF


    No structural items please, seek advice from your certifying engineer


  • #3
    BarneyMc
    Registered Users, Registered Users 2 Posts: 1,504 ✭✭✭BarneyMc


    Sorry, it wasn't meant to question the structural aspects of a truss, just the implications for attic insulation.


  • #4
    Rabbo
    Registered Users, Registered Users 2 Posts: 637 ✭✭✭Rabbo


    Structural issues aside, a shallower ceiling joist will reduce the thermal bridge effect of the timber slightly giving you very slightly better u values for a given overall depth of insulation. The difference will be small though, so I wouldnt let it be a deciding factor. Of course, you should ensure your engineer is satisfied with the proposal from the truss manufacturer first.


Advertisement