VATNIEU5110 - Simplifications: installed and assembled goods: background
Goods that are installed or assembled by the supplier are treated as supplied in the state of installation or assembly. This can make the supplier potentially registerable in any state in which they make supplies of this nature. For more details see the manual covering the place of supply of goods (VATPOSG).
The UK (along with some member states) operate simplification arrangements (in Northern Ireland only) for suppliers of installed or assembled goods who are not normally present here. This is intended to reduce the need for their having to register for UK VAT. Details of any similar arrangements that may apply in a member state should be obtained from the tax authority concerned VATNIEU1100.