New member - building a garden room

[plasteredric]

Hi all, 

I'm hoping to get a bit of advice along the way as I build our own timber framed garden building. Basically the Mrs wants my tools out the house and I could do with an actual workshop rather than just using the patio.

I've done a detailed model of how I think I should be constructing it, but could do with getting the opinion / ideals from some knowledgeable people.

So I'm thinking of doing the base as per the attached images, using 44x120 C16 timbers for the outer of the two framed sections and 44x95 timbers for the inside joists, I can then put thin battens across the underside of the shallow joists to support 90mm thk PIR insulation. The base will be going onto either ground screws or concrete piles with steel rods as we live in a mid terraced house with restricted access to the rear, plus we have a few large trees just a couple meters from the site. I'd like to keep the base as shallow as possible too to maximise the internal headroom.

My questions at this stage would be: Is my frame design okay or should I do it differently?

As there are going to be internal walls, do I need to have joists running the same direction under where the walls will be?

Any feedback would be really appreciated.

R

 

[MikeSharp01]

As long as you have joist hangars everywhere and enough piers for the outer group and across the middle and you are not thinking of installing any heavy machinery - lathes and the like, you should be OK. 

[plasteredric]

I've planned the foundation ground screws to be located at the red spots.

Should I be sistering the highlighted beams or would a singe beam suffice?