VAT Invoicing Procedures for Solar Panel Installations with Scaffold Services

The business background involves the installation of a photovoltaic system, which requires the erection of scaffolding around the building to meet the operational purposes. The scaffolding company invoices us, and we invoice the end customer. Questions: 1. “When invoice the end customer, is the VAT rate normally 20%, and does it not involve VAT exemption?” 2. “Is there an involvement of reverse charge for VAT? Do we need to obtain the scaffolding company’s VAT number and CIS registration number?” 3. “If reverse charge applies, can we only receive a net value invoice from the scaffolding company?”

Hi,
The scaffolding company's supply to you should be done under the reverse charge procedure for construction work.
Please see the following:
Scaffolding supplied in relation to standard or reduced rated construction work (contracts for the hire, erection and dismantling of scaffolding for construction work) will be liable to VAT at the standard rate. This should be accounted for under the reverse charge if all the other reverse charge conditions are met — unless the customer is an end user.
If the scaffold supplier’s invoice shows a single charge for the hire of scaffold and labour, the full value of the supply is subject to the reverse charge, unless the customer is an end user.
Scaffolding on zero-rated new build housing
Flowcharts - If you sell building and construction services
The supply you make to your end customer of the scaffolding servives will be standard rated.
Although the energy saving work you carry out can be reduced rated the scaffolding will not form part of this supply, and so the relief only applies to the services of installing energy-saving materials in the residential accommodation. 
Please see the guidance for energy saving relief below:
2. Installations of energy-saving materials.
Thank you.