Guys, we were (And still are) going to get someone in to look at it anyway. I'm not stupid enough to trust ANYONE on an internet forum 🙂

I understand your point of view but you need to be aware that just because something is generically concrete it doesn't automatically follow that it's stronger than brickwork or blockwork. No-fines concrete was used for housing because it has good insulating properties and is quick to build. It is generally unreinforced or minimally reinforced along its centre just for crack control and basically consists of 10-20mm gravel bound together with cement slurry. As such it has fairly good strength in compression and is hard to drill into – you are effectively trying to drill into the stones that constitute it – but if you apply a significant bending moment to it, it cracks due to the development of tension in the convex face. If the compression due to the weight above is insufficient it may then collapse. As such the strength of a no-fines concrete wall is broadly similar to a weak concrete block wall of similar proportions and this is no surprise since both are basically bad concrete stuck together with cement/mortar.

Just so as you know, I spent something like 6-8 years as a technician testing building materials, including 3000m3 a day on Limehouse Link in Docklands, and also 2 years as a concrete plant foreman. If there's one thing I know about, it's concrete. 🙂
What I don't know about, is construction. I've only made the stuff, not used it. What you say makes sense, but I'm not so sure it all applies here. 🙂
Remember, that double beam just to the left of the wall in my first pic supports an upstairs wall. WHich may, or may not, be a good thing: Good in that it will stop flex of the wall, but bad in that it's close to the wall that needs to come out.

We shall see. I shall report back. 🙂

I have a question trailertrash. Do these walls or nibs need to run the whole height of the house or not. It looks as though in this case it is only at ground floor level. An interesting post though and has given me something else to consider in planning taking down one of our walls. That is structural and yes I will be getting a structural engineer to look at it.

The ground floor walls resist more load from stability forces (wind and forces from structural misalignment) than the first floor walls, but In terms of wind load it's about the same. This difference is ignored in a building this size.

There may also be other structural factors at first floor that make a similar stub at first floor redundant e.g. different window layout.

Best

Tim

Just so as you know, I spent something like 6-8 years as a technician testing building materials, including 3000m3 a day on Limehouse Link in Docklands, and also 2 years as a concrete plant foreman. If there's one thing I know about, it's concrete.
What I don't know about, is construction. I've only made the stuff, not used it. What you say makes sense, but I'm not so sure it all applies here.
Remember, that double beam just to the left of the wall in my first pic supports an upstairs wall. WHich may, or may not, be a good thing: Good in that it will stop flex of the wall, but bad in that it's close to the wall that needs to come out.

We shall see. I shall report back.

Cool. However, you are thinking about the lateral stability of the walls in terms of them blowing over like books stood one end, from ground floor to eaves level? That can be one failure mode but is very unlikely as the first floor and external walls running at right angles to this one form a braced structure. The mode of failure that I am referring to is bending within the ground floor storey height itself. I appreciate that this may seem crazy to a non-engineer (a concrete wall getting bent by the wind? surely not) but that is how it is. Not only do walls fail in this manner in the real world but this is the check in accordance with BS8110/EC2 that building control will insist upon in order for your house to meet the building regulations and get approval for the wall removal and so a completion certificate. Hope this helps? This is all starting to get quite technical/abstract. The fact is that such walls are not worth anything under lateral loads in the standards as concrete is not permitted to take significant tension, such as that which develops in the convex face under lateral load. There is good reason for this – they often can't. For example, as you know, concrete shrinks when it dries, this opens cracks in all sorts of directions, tension cannot be transmitted across a crack = no bending strength – wall turns into a pile of concrete lumps, effectively a dry stone wall.

Cheers

Tim

Tim (and everyone), thanks for the advice, I'm already looking for a pro to come and look at it. I'm glad I posted this thread as we were going to just get a builder to look at it, and we would never have known about what you are saying. Now I know who to ask for proper advice. 🙂

Incidentally, 'failure' in engineering terms means anything from unacceptable cracking or bowing of the wall to a full collapse. So please don't think I am automatically suggesting your wall is going to explode if you take the stub off the back!

You're very welcome, any time 🙂

TimP – Member
We are a bit closer
http://www.qedstructures.co.uk/
and I agree with Tim

Tim

if we are plugging firms _ http://www.hop.uk.com just down the road from the above.

say hi to wadders for me tim, been a while.

Step 1 sorted – Council say we don't need planning permission. Phew!

Step 2
Structural Engineer says it's fine to remove the wall, and we'll have that in writing.

Thaks again for pointing me in the right direction fellas, much appreciated. 🙂