Exterior brick and render -best way to prepare for painting

[TonyWarrington]

I am preparing exterior walls prior to painting with masonary paint and would appreciate some advice on best way to proceed.

It looks like the brickwork overpainted with red emulsion paint this was very flaky and peeled. Underneath this is red oil based (I think!).

The cream wall I assume to be masonary paint over render. In quite a few areas this had bubbled and in some cases come away completely. I have now pressure washed the whole area and removed most of the red emulsion and the bubbled areas on the cream wall - now looks very patchy .

In the area marked A the wall has been coated with something that I can only describe as looking like fibreglass strands - this is very rough looking.

I am unsure now of the best way to proceed to prepare for painting with masonary paint so have a few questions

1. Area A. I intend to use a wire brush in angle grinder to smooth the surface prior to painting. Looking at the masonary paint manufacturers recommendations it is stated that these paints not suitable for fletton or common brick - not sure how I can tell what the brick type is. Therefore is their any product that should be used first e.g. some form of primer?

2. Area B. After pressure washing and a little scraping much of the original area remains and looks to be ok i.e. still on the wall . Can I get away with just painting over the exposed render then coating the whole wall?
Should a primer be used on the bare areas?

3. Finally down to the choice of materials. I have been thinking either Sandtex or Dulux masonary paint and need to make a decision on either smooth or textured (existing finish). Will one or the other give a longer lasting finish.

Any advice and suggestions please

 

[TheDec]

Tony.

Good evening to you.

I have studied that pic but not really knowing what system is in situ I cant really offer a stonewall guarantee.

Yet I will try for you to address your concerns with perspective. Ok here we go.

Firstly do not use a wire brush!!!! The exterior brickwork is not likley to be common brick, "Fletton" and in all intense and purpose looks to be well adhered.

So being somewhat in the dark i'm going to suggest this method of application, scrape off all loose and flaking paintwork and abrade with around 80 grit dry. With force and useing a stiff bristle brush rub the walls down, any bare areas of brickwork or the adjoining rendered wall should be painted with a slightly thinned masonry paint.


Looking at your pic I would lean toward Sandex textured, after applying your thinned out first coat finish give it to full finish apps yet it would be ok to add a small amount of water to ease application should you wish.

Dec.

 

[TonyWarrington]

Dec

Good evening to you too

Sorry but the pictures I posted were in fact prior to my pressure washing and while I can see that the paint looks well adhered the top coat (emulsion?) was flaking off badly. After washing much of the top coat was removed leaving a few traces which I will try and clean off. Underneath there was a coating of gloss paint which seems to be ok. I will try and get a couple of close ups showing wall state after washing

Another pic before power wash. This picture does not do justice to just how bad the wall looked. This is the area that contained long white fibres under/in the paint. Looks worse now it is washed off - I have no idea what it could be or its original purpose. This part of the house had a conversion in the 70's which got rid of the outside toilet to extend the kitchen. The house itself is a mid terraced built in the early 1900's

Thanks for your info

Cheers
Tony

 

[TonyWarrington]

Just a few pictures a little closer after pressure washing and a little scrubbing with a wire brush:

This part of the wall is probably the worst - scraping with a wire brush has very little effect

A closer view showing the fibres - any ideas?

Final pic this wall after pressure washing - question is how much more should I try and remove or does it all need to come off

Decided that Sandtex textured will be the best bet as suggested.

 

[Robbie uk]

The red brick wall looks like it has had a coat of emulsion over an already flaking oil based brick red paint. As TheDec says a goos abrading needs to be done prior to any further coats going on. The cream wall needs a stabilsing solution on the flaking areas and the recoat with whichever masonry emulsion you wish to use.

 

[TonyWarrington]

Thanks Robbie, peeling paint both emulsion and oil based. More work to be done abrading and I will get stabilising solution as suggested.

 

[joe-90]

I don't care for texture paints for the following reasons:

They are very rough and skin your knuckles if you brush against it.

They hold the air-born road-grime so are forever dirty.

Better in my opinion to spend time prepping then using smooth masonry.

It looks better. Not dangerous. Easy to clean.

 

[TonyWarrington]

Appreciate your view joe-90. I can see your points about being rough likely to hold grime etc. Will see how I go on with prepping - if I have the energy to do a good job will consider smooth over the texture finish

 

[TheDec]

Tony.

The application of a textured coating can hold a little more grime than smooth. In the location of which you are useing it this would be miniscule, and a good shower of rain would tend to wash it clean.

That wall "finish wise" is'nt good and a textured coating would greatly assist the overall look.

There is a saying that you cant make a silk purse out of sows ear, yet a good effort and the correct product can sure help.

The strands of which are attatched to the brickwork look very much like the filaments of a cheap nylon brush, and although you will need to remove them I dont view them as a cause of concern.

Tony.

If you in any way run into further problems, you know where we are.

Dec.

 

[wallcoatingsbloke]

Hi. I think the "fibres" you are talking about maybe simply brush hairs from someone panting previously with a cheap paint brush

My advice to you would be to do the following.

Mask up all windows and doors, as per what textured wall coating companies do before they work if you have seen that being done, then cover the ground with dust sheets.

Mix up, bucket full at a time, some sand and cement and unibond, and mix until a creamy liquid paste is achieved.

Paint this onto the wall using a thick brush and remember to brush out any brush lines lightly. (You must wear thick gloves or the cement in the mixture will burn your skin) plus dont get it into your eyes.

As you continue doing this (best to start from the top and work DOWN), you will see the "cement wash" will fill in much of the imperfections and loose pointing etc.

Then allow a day to dry.

Next day, mix up a little bit of mortar and go around and face up the old bricks, full in any large gaps etc.

Then paint a stabiliser on the wall.

Then remove the masking paper and paint 2 coats of a good quality paint.

......or get an exterior wall coating company to put a wall coating on top.

There you go, thats my advice and i managed not to make it into too much of an advert



hope this helps you.

 

[TonyWarrington]

wallscoatingsbloke, thank you for your very comprehensive reply - something to consider