Bricks or Blocks below DPC

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My architect has specified the below.

upload_2020-6-10_10-46-23.png


The walls will be rendered so blockwork to both skins above DPC. Is there any benefit to either brick or block below DPC? Blocks are cheaper to purchase and i guess quicker to lay so why do people use bricks - What am i missing?

Also there is no mention of insulation below DPC. Should a celotex type insulation be used to fill the cavity between the lean mix and rockwool above DPC.
 
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You wouldn’t render all the way to the ground, you’d stop the render at DPC and have bricks below it
So bricks unless you want visible blocks.
 
Can the bricks/blocks below DPC be rendered as long as there is a gap so as not to bridge the DPC? Bead below it and drip bead above it?
 
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Render shouldn’t be in contact with the ground.
Blue bricks with dark mortar is normally a smart looking option. Or whatever other frost rated bricks you might like
 
If you want to render above and below, use a wider roll of dpc so it extends through the render.
I filled my "water trough" with Dritherm.
 
They look different
Ok so no structural difference then purely the look if exposed.

The spec calls for turbo blocks above DPC but i have heard these can cause issues when rendering. Does using dense 7N concrete blocks give a better build (slower on the laying)?
 
If you’re rendering, then yes a dense block rather than an aerated block is more sensible for the outer skin.
 
Thanks 23vc. If plastering internally and for ease i assume that there is no issue using dense blocks on both skins (its a very small area).
 
It’s more to do with u values and there are lots of different types of block available. So generally you’d have a more dense block where it’s rendered, and either aerated or other lightweight type for inner skin
 
Is that much of a concern if using full fill 100mm cavity insulation? In the new area of blockwork i have to fix a lot of timber to the inner skin and thought that dense blocks would give a better fixing.
 
You’ll need to achieve a certain u value for the wall as a whole, so you need to work out your options with type of insulation, type of block etc.
Inner skin of non-aerated block is very common so unlikely to be an issue
 
Render shouldn’t be in contact with the ground.
Blue bricks with dark mortar is normally a smart looking option. Or whatever other frost rated bricks you might like

This is what I went with, blue engineering bricks and black mortar (tone).

I also went for 7nm blocks above DPC on the outer skin as they apparently better for rendering. I went for fibolite blocks as these are 'lighter' than normal dense concrete blocks...but I have found that although I can lift them one handed, I am not strong enough to lay them single-handed without making a mess of the placement.
 
Do the 7nm dense blocks add to the structural stability of teh external walls or is it purely to better accommodate for render/fixings. As said i have a very small area at the front so i cant see the brickie being to upset about it. The rear may be more of an issue due to the amount of blocks involved.
 

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