who is "we" ? I don't want to get into arguments over it, but what was relatively easy before is now made more difficult.
This is from the official regs...
Building Regulations Explanatory Booklet (
http://www.communities.gov.uk/index.asp?id=1131116)
From Section 3….
3.2 If whatever work your project involves amounts to ‘Building
Work’ then it must comply with the Building Regulations. This
means that if you want to:
• l put up a new building, or extend or alter an existing one
(e.g. by converting a loft space into living space);
• l or provide services and/or fittings in a building such as:
– washing and sanitary facilities (e.g. WCs, showers,
washbasins, kitchen sinks, etc.),
– hot water cylinders,
– foul water and rainwater drainage,
– replacement windows, and
– fuel burning appliances of any type;
then the Building Regulations will probably apply. This means that the
works themselves must meet the relevant technical requirements
in Schedule 1 and they must not make other fabric, services and
fittings less compliant than they previously were – or dangerous.
For example, the provision of replacement double-glazing must
not worsen compliance in relation to: means of escape; air supply
for combustion appliances and their flues; and ventilation for
health. They may also apply to:
• certain changes of use of an existing building even though you may think that the work involved in the project will not amount to ‘Building Work’. This is because the change of use may result in the building as a whole no longer complying with the requirements which will apply to its new type of use, and so having to be up-graded to meet additional requirements specified in the regulations for which building work may also be required.
From Section 4….
(r)(i) If I want to install fittings such as a WC, shower, washbasin, or
kitchen sink within my home, or any other type of building,
will the Building Regulations apply?
YES – if the installation of the fitting or fittings will involve
alterations to, or new connections to, a drainage stack or an
underground drain. You should also check with your Building
Control Service to find out how much information is required
about the fittings you intend to use.
NO – provided the work only involves installing an additional
fitting or fittings in the same or a new location which does not
involve extensions to the drainage pipework.
======================================
Still looks to me that you do need permission as you can't relocate the sink without extending the drainage pipework, even if it goes to exactly the same house exit point.