Builder removed outer leaf of old external wall - safe?

[edwardo]

I've recently had a two storey extension completed on my house. During the build process, my builder asked if I wanted the outer leaf of the old external wall removed (now an internal wall) to create extra space. I agreed.
The floor joists for the new 1st floor and the old first floor sit on this single skinned wall. The joists from the old and new parts of the house don't appear to be connected to each other or to the wall. The rectangular spaces between these joist are empty - to allow space for wiring and pipes etc. I would've expected most or all of these gaps to be filled in with brick, so that the wall was a single wall, rather than a downstairs wall with some joists on it with another wall on top of the joists!

The whole setup seems vulnerable and flimsy. I have visions of the upstairs wall collapsing and the roof joists sitting loosely on top collapsing into the bedrooms (there are no roof purlins connected to the ceiling joists - just collars connecting the rafters). Or the entire flimsy wall giving way and the centre of the house collapsing!

So my questions are:
* Was it safe to remove the outer leaf from old external side wall to creat a single skinned internal wall?
* Should the first floor joists for the existing and new first floor rooms be connected? (they sit on the now single skinned wall)
* Should the gaps between the joists be filled with brick?

Thanks.

 

[freddiemercurystwin]

What do your drawings specify/show?

 

[edwardo]

What do your drawings specify/show?

Drawings & structural calculations do not account for the outer skin being removed.

 

[edwardo]

Some pictures of the work in progress

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• edwardo
• 20 Nov 2013
• 1

no cross bracing between the joists, so the floor is now very springy. That movement makes me nervous - given my concern that the wall the joists are sitting on is flimsy.

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• edwardo
• 20 Nov 2013
• 1

The brick below the steel was removed for the kitchen. Does the beam looks a little short to anyone?

The builder bricked up one gap above the steel between the joists, but all of the rest are empty.

The joist in the loft look like this (no purlins supporting the roof joists from above)

Untitled

• edwardo
• 20 Nov 2013
• 1

 

[catlad]

It looks odd from the pictures provided, and I have never seen anyone go to the trouble of removing the outer skin/brickwork before.

 

[tony1851]

I've commonly specified the outer skin of the first floor to be removed if the width of the new extension is a bit tight. No problem with that per se, the more so because your existing roof bears on the wall, enhancing lateral stability.
However, I would not like to see the gaps left above the steel and they should be solidly filled-in.
The bearing of the steel on the r.h. side does look a bit short (1/2 brick?). If you have had calcs done for the beam, they will (or should) have detailed the padstone size; you might need a pier there.

 

[KenGMac]

I must agree with tony1851

The "bearing" of the steel beam looks "Iffy" all of the load is being carried on what appears to be a couple of bricks?

This combined with the fairly large "span" of this steel beam with the imposed load from the floor and the wall above appears "flimsy" to say the least?

All in all there appears to be a substantial "load" impinging on these bearings?

I there a "Structural Engineer" involved? or how detailed are the plans? if in doubt you could call in Building Control to shall we say adjudicate on the project?

Ken

Ken

 

[edwardo]

thanks for the replies. All the building control inspection is being carried out by a private company. I've arranged for final inspection & sign-off on Friday morning. I'll raise all the concerns with them then and see what they say.

I'm also going to bring in a domestic structural engineer to do an on-site review.

When my builder suggested removing the outer skin, I was being overly sensitive about not offending his professional judgement, so didn't push for the structural engineer to get involved. I asked him to 'run it by him', but he never got round to it.

A few weeks later whilst on the phone to the structural engineer about a different issue, I mentioned what the builder had done. He said his calcs didn't cover it. I have rather naively assumed that him not coming back to me meant it was safe enough.

 

[noseall]

A few weeks later whilst on the phone to the structural engineer about a different issue, I mentioned what the builder had done. He said his calcs didn't cover it. I have rather naively assumed that him not coming back to me meant it was safe enough.

So you just told the builder to carry on regardless?

Surely it would have been a safer bet to hold off for the sake of an extra six inches.

I personally would not advise my customers remove the outer skin.

 

[edwardo]

I didn't tell the builder to carry on regardless. I asked him to run it by the structural engineer. Later, after he'd done the work, I found out he hadn't.

The structural engineer was recommended by the builder, as were all the other trades. I'm a computer programmer, so knew very little about the whole build process. The builder was the project manager who I believed I was paying to take care of things like this. My decision was simply to decide whether or not I paid to have the outer wall removed, not to decide if it was safe to do it (or so I thought).

 

[stuart45]

When the SE said his calcs didn't cover it, you should have asked him for some new calcs.

 

[tony1851]

@edwardo;
In advising that the calcs don't cover the removal of the skin, your SE has neatly divested himself of any liability.
But from a structual aspect, What's wrong? Sure, the beam looks little short and your builder should either replace it,or extend the bearing outwards by building a pier.
The floor joists will be springy unless and until (a) he puts solid brickwork between the ends and (b) he includes bridging or strutting between the joists.

 

[edwardo]

the builder has fitted a new steel in the kitchen. He also bricked up the voids between the joists and installed noggins towards the mid-point of the joists. The floor is still very springy, so he's decided to install extra joists. He's not charging for any of it.

 

[Jackrae]

Out of interest, what's holding up the wall, above the joists sitting on the rather tricky beam.

 

[edwardo]

if you mean the steel beam, then the beam itself it holding up the wall. The gaps above the beam between the joist have been filled in with brick & slate