Secondary Glazing on FHL - is it capital expense?

Hello, I am doing a self-assessment for the first time and just trying to work out if the secondary glazing we had installed is a capital expense? We added two secondary glazed windows on a tenement flat as the single glazing was very old and there were gaps which let in drafts and a lot of noise. It would have been more expensive and required planning to change the windows and we were getting a part grant for the windows as the flat is a furnished holiday let and this was an energy grant. Can we claim expenses on the part we paid? From reading the tax guidance - double glazing is now allowed as a repair/replacement, but I am not sure if secondary is classed as the same? I believe the job had done essentially repaired the windows functioning to what they should have been? Thanks

Hi DobbyDCG,
The approach to take is to look at the asset and see what the result of the work is:
has the asset been altered or improved or has it been repaired to do the same job it was doing before.
As the latter would appear to apply here, then the cost incurred would be classed as an allowable expense.
Further information is available here:
BIM35455 - Capital/revenue divide: tangible assets: changes in technology and materials
Thank you. 
 

Thank you - that is very helpful. :)