House was built in 1928 and have noticed that the condition of the tiles on the south facing side of the ridge have deteriorated and are more brittle that on the north facing. There is no sagging of the rafters.
Is this a common situation and should I realistically be looking to retile the whole roof with new battens?
And if I put Tyvek on, can I get rid of the soffit vents that were insisted upon by the Buildings Inspector when the loft conversion was done?