Insulating between and under rafter question

28 Feb 2014
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United Kingdom
Please bear with me as I am quite new to this and a DIYer but have searched the forums for the right answer and not quite found it (though learnt loads)
I have two rooms in an Edwardian house built in the roof. There are tiles on pitched roof with no felt and plenty of ventilation. The window walls are tile hung on outside and the walls were lathe and plaster before we removed them to insulate.

I decided to insulate the full length of the rafter to gable, battening to give appropriate ventilation gap and filling rafter with Celotex. I plan to do the same on the window vertical wall.

Now my questions, if I decide I also want to insulate below rafter to increase insulation and improve u-values, should I do this over the full length of the rafter I have already celotexed including in the eaves or could I add the additional insulation up the dwarf wall and over ceiling only. Then vapour control and plasterboard.
Will this create a double insulated eaves problem with poor ventilation? It seems most people advise to only insulate up dwarf walls then along rafter a bit then ceiling but I want to build in eaves storage which is why I did full length rafter as didn't want really cold storage and eaves and the problems with that.
(I am aware of u-value requirements etc and don't want to dwell on all the thicknesses, but need help with the assembly of the insulation)
Thanks in advance!
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Hi, would really appreciate some help from someone.

Will attach some pics in case my question was confusing. Any help on what insulation to put where or changes to make before I progress more would be great!

As I said, was thinking carrying on filling rafters with Celotex, insulating with celotex between dwarf wall rafters, rock wool between the eaves floor rafters.

Then an additional layer of Celotex 25mm across dwarf wall, up to ceiling, over ceiling and then plasterboard.

Hope this works this time

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