Which flat render - STO or K-Rend etc.

[Dasbo]

Hi folks,

We are about to re-render our detached house in Aberdeenshire and I am trying to grasp what the best render to use would be.

We would like a flat finish in white, that has good weather resistance (we're 1km from the coast) and is crack resistant.

Currently, I have looked at STO, K-Rend and Powerwall renders and would just like to know if anyone has used any of these and if any issues have arisen. Suggestions of other rendering systems are also welcome.

Also, it has been mentioned that new render may be applied over existing pebbledash which has been hammer tested, but I am not sure about this. Surely I would need sill extensions etc. the house is very big so I want to make sure I get this right as I dont want the expense of doing it a second time.

Thanks in advance.

 

[Micilin]

How well is your house insulated, are you thinking of adding more?

 

[Dasbo]

Hi Micilin,

The house isnt insulated as fas as the walls are concerned. I know that a few of the companies I mentioned have insulated render systems, but I'm not that keen on the additional cost or the fact that my window sills etc. will have to be replaced due to the extra width of the render. So we are considering normal cavity wall insulation instead. But I'm not completely discarding the idea.

 

[external]

over cills cost pennies,you can go over the old as long as its sound,if you hack off you need to upgrade the insulation by regs,all the systems you mentioned are more or less the same,you need to find a good spread who works with poly/resin morters regular to get a good job,they will all fail if done wrong!

 

[Brian4069]

Dasbo,
I have a bit of knowledge on this subject - if the render as you suggest is sound - I would recommend a Polmer modified Render Basecoat is applied in one coat - 10 -12mm thick over the existing dry dash. Then either an Acrylic or Silicate Render Topcoat is applied. Best Company to use for this would be Structherm Ltd - find them on web.
They have Contractors working in your area cladding 300 No. houses for the Council - albeit with a dash finish.

Stay away from the K Rend & Powerwall Scratch Plaster finishes - very hard to put in well & prone to cracking - look at the stair well of the AECC & you'll see what I mean.
Even if applied well - will catch dirt & look grubby in a few years

Best not to fill the cavity as it can cause condensation issues with the existing structure.
If you can afford it - Insulated render is the way to go - you'll save a fortune on your heating Bills.

Given you're location - I would suggest a Silicate Topcoat - higher performing than Acrylic - cost 50 p/sq.m more.

Cills don'tneed to be replaced - an Overcill or Undercill can be installed - this is made from powder coated Aluminium.

Ensure that Stainless steel beads are used for Movement Joints etc - other ones will rust.

Hope this is of use

 

[external]

brian4069 is quite correct,we are registered applicators for strucktherm,the fibre basecoat is like iron,if a little difficult to use ,can only be floated and wont take a sponge,but the acrylics are the best i've used,flesscoat tonachino stands out and holds its color very well.

 

[Micilin]

Would plastic beads be better ?

 

[external]

not with the above system m8,that gear is full weight render as opposed to light weight/tight coat and you really need to bully it with the edge,i could see plastic moving,i did twenty houses with only base bead,all angles were hand made but once set they were rock hard ,mind saying that a tight coat system would do the same job and use plastic bead.(an be a damn site cheaper!)

 

[Micilin]

External, have you used the metal beads with plastic sleeve/trim? Would they be better?

 

[external]

yes m8,top beads for flat/dash/mono,but not for texture,bit blunt if you get my drift.

 

[Brian4069]

Best to use powder coated stainless steel beads with plastic nosings. Depending on the colour of the render - these can also be colour matched. The powedr coating means you don't see any bare metal that would look cheap.
The bead provides a sharp edge to work to. You hardly see the nosing once the render is applied

 

[external]

give us a link to those powder coated stainless beads with th plastic nose m8.

 

[Brian4069]

www.wemico.com

think they@re in your kneck of the woods

 

[external]

yes m8 we deal with them , but i cant see the bead you speak about.

 

[external]

Best to use powder coated stainless steel beads with plastic nosings. Depending on the colour of the render - these can also be colour matched. The powedr coating means you don't see any bare metal that would look cheap.
The bead provides a sharp edge to work to. You hardly see the nosing once the render is applied

brian,if you used the system you quoted all beads are covered anyway m8 so i wouldn't have thought that would be a problem!