How much difference does external rendering make to insulation.

Question

We recently moved house and our new house (a 1930s house) has solid walls which are rendered ~1½" thick and looks less than 5 years old (the rendering that is). The EPC for the house recommended installing Internal or external Wall Insulation (in lieu of there being no cavities to fill). Thing is, we've already proved the EPC wrong in a number of areas already and therefore would like to know how much difference rendering actually makes (in comparison to our neighbour who has exposed brickwork) so that we can see how much this improvement would actually be worth.

Anyone with an expert opinion out there?

Answer 1

i cant give you a figure but they are saying to put insulation boards

on externally, typically expanded polystyrene type material then render over, or

internally, insulated plasterboard or make a cavity and insulate and

yes they will give improved insulation values but you need pro advice on the exact figures, they would need to know the construction and installation details

Answer 2

http://www.walltransform.co.uk/

Have a look at this product. Might be of some interest.  

Answer 3

Hi Sadie..

The render will make little difference to the insulation .. you should go ahead as if there were none,, also check at low level as this may actualy breach your damp proof course.

Answer 4

I'm not certain but I believe the answer is very little insulation unless it's a special type of insulating render.