Problems with Sand-Cement Napped Finish - Advice Needed

rainmaster

New Member
I am looking for some advice on issues that I am having with the exterior plaster on my house. It was constructed about 8 years ago as a new build and i recognised issues shortly afterwards. The main problem is that the nap is very weak for instance if I rub it with my fingers some of it will come off I.e. the grains of sand and cement. I havent painted the house because I had concerns that the paint would,d not adhere or the paint would start to fall off in patches. Personally I don't think that the plasterer used enough cement in the mixture at the time of application but I could be wrong on this. It just appears a bit sandy. Anyway it's getting to the stage now where I need to do something with it because it has a pretty dirty appearance now due to 8 years of weathering. Last year for about a week snow lay against part of the plastering at a low level and removed the nap through freeze-thaw action.

I'm seeking advice from some of you guys outlining my options to stop any further deterioration. For example would it help if I mixed up a cementicious slurry and applied???

Any help or advice would be greatly appreciated.

Thanks so much
 
With a pourus sandy render i have tried going over it with sbr in the past to try and stabilise it, do a 10sqm test patch and see what it's like.
 
You need to tap the render to find out how much of it is hollow before you remove it, it's been on for 8 years so can't be that bad,if you are in the south east you will probably be using pit sand which is s**t compared to dredged sand which is much coarser . If it's all hollow get it off and redo, if only a small portion of it is hollow try a silicone system over the top., but do try sbr has worked for me in the past .
 
Thank you for the replies.

The thing is. . . . . It's not hollow. I have tapped several areas all over the house and it hasn't lifted anywhere. There is a small section at the rear where some hairline cracking has developed like spider webbing but it was there from the early days and has not worsened at all. Apart from that there is just the minor cracking you see on other houses like underneath cills.

I was going to get a former colleague who is now into concrete and structural testing to do a few areas and confirm that it is stable.

However if it is ok my main concern still remains. How do I stabilise the nap and stop it from deteriorating any further.

Thanks again for the help.
 
Hi Mark, can you just explain to me what an sbr will do and how will it make the plaster look after applying?? Would I be able to paint it afterwards??

Thank you
 
dont paint it or u b rightly fecked. it prob has a hard-core within so u might have the option of diamond core grinding discing the plaster back to this, sbr scud, and a top coat. But in all honesty, it may as well be kango'd off with all that work. Get a well known, 20year+ exp plasterer to look at it.
 
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