Author Topic: Failling brick blocks ceiling in future baby room...  (Read 1149 times)

GilbertB

  • Stubble
  • **
  • Posts: 118
  • Age: 40
  • Location: Gent
    • Sci-fi Meandering
Failling brick blocks ceiling in future baby room...
« on: December 12, 2016, 07:23:33 AM »
I have not a lot of knowledge of how fix this, other than "Break and start again"... And that ain't cheap!
I'm more of a "brick work vertical & wood horizontal" kinda guy...

The is the renovation of a bedroom in a 1965(ish) brick and mortar house that we gott cheap because it was a wreck.
I was investigating some bulges in the ceiling before re-plastering it and got a shocker... Some bricks/blocks are falling out!

The bricks work containing the concrete rafters is fine, the concrete is actually hard as nails.
It's the cement between the rafters and the "filler" blocks that is failing. The floor above shows no traces of caving in.
I suspect that this is due to the house having been "humid" for 40 odd years and us insulating and waterproofing it, leading to a wee bit of movement.

As you can see on picture 1, the drop is about 2cm and the bricks can be moved upwards by hand...
My solution, possibly over-engineered, would go as follow (image 4):

1) Push back in place, remove failed cement.
"Glue" together using hi density PU foam.
Partially fill hollow block to avoid failure when installing stud ceiling.
2) Wait 12 hours, put a diagonal anchor every 40cm(ish).
3) Install a standard 3*2 stud + OSB ceiling to prevent this happening again...

paddedhat

  • Handlebar Stache
  • *****
  • Posts: 2238
Re: Failling brick blocks ceiling in future baby room...
« Reply #1 on: December 14, 2016, 07:26:46 AM »
Interesting, and nothing that you typically see here in the US. I wouldn't really be too comfortable with any patchwork solution, and would go for the ceiling joist, OSB, and plasterboard method you propose.  If you are doing any anchoring of the wooden ceiling joists to the existing concrete, don't forget that the use of a hammer drill might result in at least some additional loosening of the brick fill, or worse. What is the reason for the brick fill in the first place? Is it just a surface to plaster, or something more? If you are going to install a new ceiling under it, is it feasible to remove ALL the fill brick in the room?

GilbertB

  • Stubble
  • **
  • Posts: 118
  • Age: 40
  • Location: Gent
    • Sci-fi Meandering
Re: Failling brick blocks ceiling in future baby room...
« Reply #2 on: December 18, 2016, 01:30:30 AM »
This type of construction is more typical for commercial or appartement buildings, and makes my life complicated!
The brick fill was done from above on temporary planking.
After removal of the support, it got 2 layers of plaster, the 1st mixed with straw.
Removing all the brick fill is not feasible in the timeframe I've got:)

I first stabilised the problem area by pushing the falling bricks back in.
It was not possible to push them all the way in as they were beginning to snap.
However, the worst point went from 25mm to about 8mm, a defect that can be plastered out later.
During this I discovered that the concrete was both of high quality and filled with small pieces of metal, not really sure if they are old nails and shavings or purposely cut pieces of wire. This is something I've seen in German bunkers but ever for a house!
In any case, the concrete is too hard for my planned 5mm drill bit. The next size up is 8mm, and the first one of those burnt up in 5 holes before I managed to interpret the readings on the stud finder...
The shavings would make it give a maxe reading EVERYWHERE! A distance of 25mm sorts out the the main steels, but it's not perfect.

The rest of the ceiling is now stripped and ready for the remaining joists, OSB etc.
« Last Edit: December 18, 2016, 01:33:43 AM by Gildasd »

GilbertB

  • Stubble
  • **
  • Posts: 118
  • Age: 40
  • Location: Gent
    • Sci-fi Meandering
Re: Failling brick blocks ceiling in future baby room...
« Reply #3 on: February 16, 2017, 03:19:41 AM »
OSB'd the ceiling and drywalled the the walls.

ShoulderThingThatGoesUp

  • Magnum Stache
  • ******
  • Posts: 2799
  • Location: Emmaus, PA
Re: Failling brick blocks ceiling in future baby room...
« Reply #4 on: February 16, 2017, 03:25:06 AM »
And I bet you have a much stronger neck from all the looking up, too! Interesting situation; thanks for sharing it.

GilbertB

  • Stubble
  • **
  • Posts: 118
  • Age: 40
  • Location: Gent
    • Sci-fi Meandering
Re: Failling brick blocks ceiling in future baby room...
« Reply #5 on: February 27, 2017, 02:58:30 AM »
Plaster and paint done... 24h left to finish before baby!
« Last Edit: February 27, 2017, 03:01:15 AM by GilbertB »