Addressing differential depth of Brick Slips vs Render

[Mulberry View]

Our external finish schedule is brick slips at low level, with render on the upper level, as per this detail.

 

A local K-Rend applicator has told me that their build-up is likely to be no more than 8mm for thin-coat render. The slips are like to be in excess of 30mm, resulting in a more pronounced version of what our Architect drew. It feels strange to have the upper finish not overhang, or at least level, with the lower finish. Would you agree?

 

What would the process be for adding, say, 30mm of EPS to the areas that will be rendered in order to create this effect? Would get rid of the need for the Aluminium flashing, would it not?

[Redbeard]

3 hours ago, Mulberry View said:

Would get rid of the need for the Aluminium flashing, would it not?

Some would say not. Like base-rails for EWI, some like a 'proper base'. If your upper layer is to oversail the brick slips it will still need a drip at least, to reduce the risk of the worst-case scenario which is water tracking back into the junction of the 2 layers.

[Andehh]

If you give me a couple of weeks I can show you. We have this predicament in a couple of areas and I'm not sure. Builder has delivered the aluminium trims already, but a week or two before they are installed or at least trial it,

[Mulberry View]

2 hours ago, Redbeard said:

Some would say not. Like base-rails for EWI, some like a 'proper base'. If your upper layer is to oversail the brick slips it will still need a drip at least, to reduce the risk of the worst-case scenario which is water tracking back into the junction of the 2 layers.

 

I would presume the renders will install a drip bead at the bottom of their work? If that protruded beyond the brick slip layer, would that be sufficient? Though, with that said, I wouldn't want to 'see' the EPS on the underside of the ledge (albeit tiny) created by the added EPS

[Mulberry View]

18 minutes ago, Andehh said:

If you give me a couple of weeks I can show you. We have this predicament in a couple of areas and I'm not sure. Builder has delivered the aluminium trims already, but a week or two before they are installed or at least trial it,

 

I'll be very interested to see your scenario, do you have render over brick like us?

[Andehh]

Yes, pics below... On the interfaces we need to tidy up...

 

Front of the house is a 90 degree meeting of cladding and render.

[FM2015]

I would check that anyone providing warranty/BC is happy with k rend on Nudura.  Seems to be a different edict every month on renders.

[Mulberry View]

2 minutes ago, FM2015 said:

I would check that anyone providing warranty/BC is happy with k rend on Nudura.  Seems to be a different edict every month on renders.

 

Hadn't really thought of that, what's the concern from BC point of view?

[Mr Punter]

They often like to see a drained / ventilated cavity.

[FM2015]

1 hour ago, Mulberry View said:

 

Hadn't really thought of that, what's the concern from BC point of view?

Paperwork 🤣

Honestly, not really sure.  Obviously Nudura are pushing their dryvit brand.

 

Different adhesive properties on different densities of background.