On 25/09/2011 21:54, Lee wrote:
I realise this is a bit of a strange question, my S-i-l has a rental
property with a bath but no shower mixer, ie just two separate bath taps
and would like a shower but isn't allowed to change the taps.
Normally one of those rubber things would do but these are strange
shaped taps...

Can't see why there would be a problem with changing the taps to one
with a built-in mixer valve: it would be a straight like-for-like swap
and the original taps could be replaced at the end of the tenancy with
no detriment at all.

My concern (which extends to your original plan too) would be that the
walls/bath etc are not properly sealed and set up for a shower, and that
there would be leakage - S-I-L would undeniably be responsible for the
damage.

David