Roller or Brush to external walls

[dabaldie]

I', about to repaint my house.
Its stucco rendered with smooth finish.
Would i be better using a roller or brush to paint?.. ie which will be quicker with a decent finish?
I've also noticed that the previous paint has a thicker layer.. almost resin like underneath. This is obvious wher it has blistered and cracked and fallen away.
Do i need to seal these holes? or just paint over the top after dry weather?

 

[Zampa]

Ever noticed sides of houses with big square patches, thicker bands of paint making up the boxe's?....thats because they have been done with a brush and the overlaps are dry by the time the next section is painted.

A roller will sort this out..long woven pile are ideal....try and keep one edge going all the time and dont do it on a boiling hot day in sunlight.

As for the stuff underneath.....not much you can do about it really....scrape off the loose and paint over it. The resin type suff could be so many things....you never known what people have slung on in the past.

Or it could be saponification...which is a soapy gluey stuff cuased by oil in the paint reacting with alkalies in the render.