Re-rendering advice please

Cautious_Optimist

I am thinking of having my house re-rendered.
Mid-terraced, built 1905.
Currently spar dashed, same as neighbours.
Quite exposed, especially at front (west facing).

Is it better to have all the old rendering removed first (expensive?).

Or is it ok to just "score" the existing render with an angle grinder and then spread new render on top? (Cheaper?)
Or will this "double layer" of render be too heavy and start pulling away from the brickwork?

Would be planning to reapply spar dash to new render.

Thanks

nobulljusttruth

Is the existing render bad, loose, cracked, causing damp , painted, all these make a difference.
I am not sure why you think removing the old stuff is expensive. ??

Any of the above are a good reason to remove the old stuff, if none apply, why not just paint it ??

Note , silicone based renders are lighter, coloured and breath so are a bit more expensive but offer a better long term finish to concrete (cement based),

MX5huggy

http://www.moneysavingexpert.com/news/utilities/2014/10/green-deal-fund-to-reopen-with-an-extra-100mWhen re rendering building regulations requires you to insulate the walls if they currently aren't. External wall insulation is better than internal. The Green Deal home improvement fund is reopening which previously was giving £6000 towards costs.

Davesnave

MX5huggy wrote: »

http://www.moneysavingexpert.com/news/utilities/2014/10/green-deal-fund-to-reopen-with-an-extra-100mWhen re rendering building regulations requires you to insulate the walls if they currently aren't. External wall insulation is better than internal. The Green Deal home improvement fund is reopening which previously was giving £6000 towards costs.

Perhaps a stupid question, but assuming one has to put on external insulation, what happens to all the windows/sills? Will they all need moving outwards?