How do I work out the load carrying limit for timber?
Making a frame out of square timber, maybe
88 x 88mm 2.7m H3 KD Clear Primed FJ Laminated LOSP Pine Post
Structurally strong - GL8 graded for load bearing applications, stronger than equivalent F7 solid posts
But I would like to know what load it could take at the 2.7M span supported at both ends?
Maybe something Mitchell can help with, the manufacturer has this to offer -
Using a post as a beam does change the way loading works on the section, 45mm x 90mm if there is a GL8 beam and double the result. You may have to work off F7 values though.
Welcome to the Bunnings Workshop community @Dave2. It's great to have you join us and many thanks for your question.
I see you've already received a helpful reply from @Brad which is fantastic.
I've spoken to the manufacturer to confirm, as @Brad mentioned, those posts have significant load-bearing characteristics in a vertical orientation. In order for someone to determine the load-bearing characteristics in a horizontal application there would need to be designs provided as to how this load is being dispersed. The manufacturer has recommended that you consider using F7 timber which is designed for that purpose and testing plus span tables are available.
Since the posts are designed to be used in tension, if you wished to use them in a horizontal orientation to bear weight, you would need to seek the assistance of an engineer to determine what load-bearing capabilities they had over a 2.7-meter span.
Please let me know if you needed further information or had any questions.