Zero Vat on house renovation insulation

Hello everyone, i have been looking at VAT rates for doing our renovation and adding lots of energy saving materials, like converting single skin walls to double, adding cavity wall insulation, loft and roof insulation, along with solar and heat pump. It seems to be saying we dont pay VAT on insulation or labout involved with adding it to our property. https://www.gov.uk/guidance/vat-on-energy-saving-materials-and-heating-equipment-notice-7086 VAT Notice 708/6 section 2 seems to say i should be able to claim all this back from either the supplier (builders merchant) or installer (builders) or actually not paid it in the first place. it was and will be our main residence after its finished and we have paid builders/contractors to do all this work. i understand not many small builders will know about this as it only came into play in 2023, but i reckon i could claim back thousands? Please can someone advise? I spoke to a tax helpline from gov UK and spent 20 minutes explaining and was told by them i shouldnt have paid it, but want to know the route to claim this money back. Thanks Tom

Hi,
If the works meet the conditions in notice 708/6 then please contact the business who installed the energy saving materials.
Please refer them to the guidance you have looked at and if they are satisfied that the conditions have been met then the supplier can raise a credit note
to correct any VAT overcharge they calculate and they would refund this back to you directly.
If the supplier has any questions about this please ask them to call the VAT helpline on 0300 200 3700.
Thank you.