This is all I can find in the various statutory instruments including the latest Road Traffic Act.
I'm all for safety and certainly prefer towing with two extension mirrors. If my mirrors can pass through a gap there's every chance the caravan will as well.
But I do not believe there is any Legal reason why I have to use extension mirrors. No doubt one of the learned Insurers will reveal their source of knowledge.
Thus I suspect "technically" Surfer is correct. Is this not another matter like the good old "85% rule"
Lutz reference to EU Legislation is probably valid if I am towing in Europe but I don't see how it can modify English Law without Parliament passing another Law
???
S T A T U T O R Y I N S T R U M E N T S
2005 No. 3165
ROAD TRAFFIC
The Road Vehicles (Construction and Use)(Amendment)(No. 4)
Regulations 2005
(c) where the bottom edge of an exterior mirror is less than 2 m above the road surface
when the vehicle is laden, that mirror shall not project more than 20 cm beyond the
overall width of the vehicle or, in a case where the vehicle is drawing a trailer
which has an overall width greater than that of the drawing vehicle, more than 20
cm beyond the overall width of the trailer;
(d) where the bottom edge of an exterior mirror, which complies with the requirements
of Community Directive 2003/97 or 2005/27 or ECE Regulation 46.02, is less than
2 m above the road surface when the vehicle is laden, that mirror shall not project
more than 25 cm beyond the overall width of the vehicle or, in the case where the
vehicle is drawing a trailer which has an overall width greater than that of the
drawing vehicle, more than 25 cm beyond the overall width of the trailer;