New Build Double Skin Garage to Workshop

[jrjohnson87]

Just about to start a project to insulate and board out my single detached garage so it's more practical to use as a workshop. It's a newly built double skin with external bricks and internal blockwork. Roof is a 'W' truss system.

My plan was to first install a personnel door to allow access from the garden without opening the main door. Ideally I'd like the lintel to be invisible. Is this easy enough to retrofit a steel lintel vs a pre-stressed concrete lintel - which seems to involve removing some bricks, propping and then installing the concrete lintel. And is there anything to consider with the fact it is double skinned? The door will be going to the gable end of the structure.

Then I was going to plastboard the ceiling rafters and batton the wall (with treated battons and DPM between the brickwork and battons), before boarding with a plasterboard/insulation product like Celotex PIR bonded to plasterboard.

Finally, I'd add a couple of plywood sheets to roof area for some light storage (Christmas decorations etc), adding some noggins to facilitate a loft hatch to be installed.

Anything obvious I've missed or overlooked?

Cheers!

 

[Bonni]

Yes to removing some bricks for a Catnic lintel, less work with visible concrete lintel (spanlite outer, 6x4 inner). Insulation, should be minimum 60mm if concrete blocks, and 50mm if medium density blocks. Plasterboard, I would include a vapour barrier so foil backed would be the route I would take. Rafters 600mm centres require 15mm plasterboards or 12.5mm with noggins. Rafters 400mm centres, 12.5mm plasterboard.

Walls that are single leaf, needs an insulated stud wall erected inside the garage so it's not touching the outer leaf. If there's an inner leaf, you can direct to fit to the face of the inner leaf.