VAT on energy saving materials

I am a contractor completing a big refurbishment project. Subcontractors have installed energy saving materials as part of the refurbishment. Do I charge the client the reduced rate of 5% (I'm in Northern Ireland) for the installation of the energy saving materials or do I still charge the 20% Standard Rate?

Hi
As long as the conditions are met for the installation of energy saving materials in Northern Ireland then the work would be charged at the 5% rate.
Please see the link to the guidance below:
Installations of energy-saving materials
Thankyou.
Regards.