How to fix timber wall frame bottom plate to a timber foundation?

[akakb]

Hi all

I've embarked on a small project to build my daughter a cubby house. I've elected to go with a full timber design, with timber wall frames and a bearer/joist timber foundation. I have a dilemma and can't find any online resources to help. How do you secure the bottom plate of the timber wall frames to the joists/bearers? Coach screws and washers? Steel straps and nails?

I've uploaded some images to help illustrate my problem. The joist spacing is not correct, nor is the number of joists. It's more to help me visualise what I'm about to do.

Bearers double 90x45

Joists single 90x45

Posts 100x100 H4 posts in concrete or stirrups set on top of concrete, not sure yet. Building on a sandy WA surface.

Dimensions roughly 3m wide by 2.5 deep.

Thanks

akakb

 

[MitchellMc]

Welcome to the Bunnings Workshop community @akakb. It's brilliant to have you join us, and many thanks for your question about attaching a cubbyhouse to the base.

I'd plan your spacing of the joists to align with the walls. It would then simply be a process of screwing straight through the bottom plates into the joist with long bugle screws or coach screws. I've put a couple of renderings together below to illustrate. Sorry, I got a bit carried away; I love cubby houses.

Please let me know if you have any questions.

Mitchell
 

[akakb]

Thanks @MitchellMc. Really appreciate the level of detail behind your response.