insulating old stone wall

[junglejim01]

2 things i'm trying to work out:

I' insulating a room in an old sandstone building. The internal walls are rendered but externally is lime pointed. I want to insulate so was planning on building studwork against the old wall with 25mm air gap, insulation between studs, then plasterboard ontop. Just checking i'm on the right lines?...and should i ventilate from skirting board level to enable airflow?

The second issue is how to build a batten/stud wall against the original stone when the original wall is very wonky!...any suggestions very welcome!

Thanks

 

[ajmoore1]

Build frame work out of 50mmx50mm studs at 400 centres. Fix to floor and ceiling and in the centre if required. Fill In between the studs with 50mm kingspan/celotex.

Toasty!