cavity wall concrete infill to ground level

According to the plans, I have to fill the cavity of the cavity wall I'm building with a "weak mix" of concrete up to ground level and sloping down towards the external leaf. What would be a suitable weak mix to use here ? Also, anyone know why a weak mix is specified for this use ? Thanks, Simon.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Why not make it an insulating mix, either with polystyrene balls as the ballast or aluminium to get foamed cement. I
NT
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 5 Jun, 23:33, snipped-for-privacy@care2.com wrote:

Just read this. Interesting idea. I have an image of that canoe foaming incident with arms and a head sticking out of a solid aircrete block ! Suppose I have to do what the BCO expects really. I got the answer off paving expert. I usually do concrete 1-2-4, weak mix stated as 1-3-6, nice and easy to remember. Anyhoo I'll probably use a jumbo bag of ballast about 1-8, just about the amount I need. Cheers, Simon.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.