Replacing facing bricks with new ones on 1920s house, but no wall ties!

[Bounce]

I need some advice on replacing the bricks on the lower half of an external wall on our 1920s home.

 

The top half of the wall is currently rendered, and we eventually plan to re-render the entire house to match a new, lighter aesthetic.

 

Our current focus is on removing the existing red bricks from the bottom half of an external wall and replacing them with light grey bricks. We've noticed a gap of approximately 10mm between the outer brickwork and the inner wall. There's no existing insulation in this gap, so we're planning to add insulating plasterboard to the interior.

 

A significant concern is the apparent absence of wall ties connecting the outer and inner walls.

Given these observations, what's the best approach to replacing the bricks? We're particularly interested in understanding if this is a straightforward "swap" of facing bricks, or if more extensive work is required due to the lack of wall ties. The chimney breast on the inner wall is coming out, so the inner wall on the bottom half may also be rebuilt with blocks. 

 

Also if there is no wall ties in the bottom half, we don't know about the top half. We are going to have the chimney breast removed from the top half, but may not need to rebuild that part of the wall, not sure at this stage.

 

Our goal is to ensure the job is done correctly when we instruct a professional.

 

Any guidance you can offer would be greatly appreciated.

[Redbeard]

Firstly, as you appear to describe it, it is not a cavity wall. Is it all stretcher bond (long bricks only visible?). On a 'solid'  (never mind about the 10mm gap - it's effectively solid) wall the ties are in the form of bricks laid at 90 degrees, so for example you may see: header (short brick, i.e. brick laid across the 2 skins); stretcher (long brick), stretcher, header. Other patterns are also available. Can we see a picture?

 

Why are you replacing the bricks if you are going to render?

[Bounce]

16 minutes ago, Redbeard said:

Firstly, as you appear to describe it, it is not a cavity wall. Is it all stretcher bond (long bricks only visible?). On a 'solid'  (never mind about the 10mm gap - it's effectively solid) wall the ties are in the form of bricks laid at 90 degrees, so for example you may see: header (short brick, i.e. brick laid across the 2 skins); stretcher (long brick), stretcher, header. Other patterns are also available. Can we see a picture?

 

Why are you replacing the bricks if you are going to render?

Bottom half will be grey brick and top half will be render. So the grey brick won't be rendered. 

 

I've attached a bit of the wall is exposed. 

[Redbeard]

13 minutes ago, Bounce said:

Bottom half will be grey brick and top half will be render. So the grey brick won't be rendered. 

But you said:

 

1 hour ago, Bounce said:

we eventually plan to re-render the entire house to match a new, lighter aesthetic.

 

14 minutes ago, Bounce said:

I've attached a bit of the wall is exposed. 

 

Can you show us a bit more? The 'half-bricks' we can see could be headers (the ends of long bricks) but if that's an opening to the right they may be 'true half-bricks'

[Bounce]

4 minutes ago, Redbeard said:

But you said:

 

 

 

Can you show us a bit more? The 'half-bricks' we can see could be headers (the ends of long bricks) but if that's an opening to the right they may be 'true half-bricks'

 

Sorry i was meant to say part grey brick and rest render where there is no grey brick. 

 

I've attached another photo that's all of the exposed element currently, I will try take a better one tomorrow. 

 

Now looking at it the small bricks look like they could have been used to bond the two walls together? 

[ProDave]

The picture above, are all those half brick ends we see cut off as you removed ne skin?  If so as @Redbeard says they are the bonds.  Now they are cut off your new "outer skin" won't be bonded to the inner.

[Bounce]

2 minutes ago, ProDave said:

The picture above, are all those half brick ends we see cut off as you removed ne skin?  If so as @Redbeard says they are the bonds.  Now they are cut off your new "outer skin" won't be bonded to the inner.

 

I've got a feeling thats what they were. The inner skin will be coming out as part of its a chimney breast, and have to be rebuilt with blocks or something I assume. Is it possible to bond them together if rebuild the inner skin of the section?

[ProDave]

I think I would stop right there.  You are dismantling an existing wall with no knowledge of it's construction and no clear idea how you are going to rebuild it and if that will be structurally sound.

 

I think you need professional advice before you go any further.

[Bounce]

5 minutes ago, ProDave said:

I think I would stop right there.  You are dismantling an existing wall with no knowledge of it's construction and no clear idea how you are going to rebuild it and if that will be structurally sound.

 

I think you need professional advice before you go any further.

Yes we've stopped, hence checking, and looking to get someone. Just wanted to get an idea on what needs doing, to make sure it's done properly. 

[Mike]

40 minutes ago, ProDave said:

I think I would stop right there

Agreed. You can't remove half of a sold brick wall and rebuild the removed half in new bricks as is currently being done; it's almost certainly not going be structurally safe. And, since you're not replacing like-for-like, you also need Building Regulations approval.

[Redbeard]

Ooh err! Only just seen your 2nd pic. A little unnerving! Agree with @ProDave and @Mike re ?? stability. I think your plan to completely re-face the wall is at best ambitious. Even if you drop the plan now you still have a 2nd skin to build which will not be tied-in as it once was. You will have to fit screw-in ties to the old wall so that the new bricks can be tied in, or perhaps you could do it with resin anchors.

 

As you refer to plans to insulate internally can I suggest that you 'check-in here at planning stage for that? Interstitial condensation risk, possibility of thermal by-pass, possibly lack of continuity of vapour control layer (VCL) (or indeed the insulation itself)and plenty of other risks worth running past those who have done it before. Remember that, under the Building Regs, you will be 'Renovating a Thermal Element' by 'adding or replacing a layer'. You cannot just put on what you fancy - you have U value targets to meet too.

 

I am more of a fan of rigid wood-fibre than I am of insulated plasterboard - how do you keep the VCL 'tight'?

[Redbeard]

To add to my post above, you almost certainly need a structural engineer (SE) and a written specification for 'making good', particularly if you still propose to remove the full ground floor outer skin. I would expect a SE's spec to include for temporary propping while you remove the ground-floor support for the outer skin and leave the outer skin intact on the first floor (if I have understood you correctly). I accept the inherent tendency of bonded bricks to, well... bond, but  the phrase 'hanging in the air like bricks don't' also comes to mind.

 

Re Building Regulations (both stability and thermal performance), you will at very least need to submit a Building Notice (short-form minimal information application for Bldg Control approval) and BC will almost certainly issue a counter-notice requesting further details, including structural ones.

[Mike]

And I've a further thought too - what's been done at damp proof course level? There's a risk that it may have been damaged or become discontinuous - it need checking out.

[Sparrowhawk]

23 hours ago, Redbeard said:

I think your plan to completely re-face the wall is at best ambitious.

 

Yes. Round here people slap thick render over the downstairs bit to hold the soft red bricks on the lower half together, and if they want contrast add cedral cladding or similar to the top half. Or render it all the way up.

 

If it were affordable to "swap out" the lower half of the brick walls for new brick people would be doing it, because the houses which are still like that look cracking.