I find myself at the other end of the country this week - down near Southampton to build a a "Tim". This greenhouse is like the "Steve" with it's reduced height porch but I've made the porch a little wider to give more height to the entrance and it's a little longer at 4m.
The downside for Tim is I will have to contruct the greenhouse entirely back at my workshop to make sure all the valley glass works so it takes longer to work everything out and get back. The next person to choose a Tim doesn't need to worry as all the dimensions will be on file.
The greenhouse almost completely fills the space my customer wants - which is why it measures 4m by 3.5 of course.
I've also been asked to add a long cold frame along one wall and the hardwood crested ridge (mahogany). This greenhouse will be made from the standard tanalised timber - which will make a nice change after all the accoya ones I've been making lately.