Falling concrete

Pinoy adventure

Hi all

we have an overhang in concrete with steal bars inside which is exposed too the rain and sun from above.

there is a small drain in one corner.

however Twice lumps of concrete have fallen off the main piece of concrete above.

any thoughts of how too prevent this from happening again ??? Or advise on what too do with it ??

One section is right beside a light with is alarming as the wires comes from above.

one spot is inside and one spot is outside.

thanks

MrMusician18

What has happened here is that water has penetrated the concrete causing the steel to corrode and expand.

The only way to treat this is to take all the concrete cover off back along the underside to uncorroded steel, clean the exposed steel and then cover over with a repair mortar.

It might be easier to replace the whole slab tbh.

10-10-20

https://www.boards.ie/discussion/comment/119139814#Comment_119139814

Correct, it's called "concrete spalling". There are lots of guides on it online following some recent high profile failures. It's a sign of water ingress but is likely to not be just isolated to what you can see spalling.

If the concrete is structural or causing a safety concern then you need to engage an engineer (not a builder initially).

Wildly Boaring

This some type of a porch?

If so there is obviously water getting down through it.

Over time with freeze/thaw action and possibly initial defects you get this effect.

The first photo, of the exposed bars looks a simple fix. Clean back and use a propriety concrete repair.

The second photo, with the light is more worrying and would need investigation to see where the ingress is occurring. Unusual to get this type of damage in the middle of a slab.

As above get an engineer

Pinoy adventure

Wildly - no it’s the ceiling in a room.

it’s the floor above where this issue is and it’s coming true the slab downward.

Wildly Boaring

Is it a roof above it though? It's a flat roof? Not a ceiling.

Pinoy adventure

Wildly no it’s the floor of a balcony.

hayse

What floor balcony?

10-10-20

https://www.boards.ie/discussion/comment/119150805#Comment_119150805

What people are asking is: how does what we see in the photos relate to what's above the damage. We can't see the structure and we can't join the dots in terms of where the light is in respect to the spalling. Can you help us join some of the dots by describing (using photos preferably) how the whole slab is mounted and what's above, etc.

It's purely out of curiosity, mind you, but the inquisitive bunch that we are keep us asking for more.

Wildly Boaring

https://www.boards.ie/discussion/comment/119151276#Comment_119151276

Yeah sorry, I'm trying to work out what is above that floor.

You've said previously it's a ceiling, which to me would be inside and would be strange to see such damage inside.

But it it's the floor of a balcony, it is exposed to the elements and people stand on it?

If so i'd be blocking it off above and below until someone who knows what they are doing looks at it. The photo with the light in it is concerning to be honest.

Pinoy adventure

https://www.boards.ie/discussion/comment/119152700#Comment_119152700

Yes it’s exposed from them top.and the room where the light is,is a persons bedroom so hard too block off.

Wildly Boaring

Well then get a local engineer to look at it. Id not sleep under it.

10-10-20

https://www.boards.ie/discussion/comment/119154586#Comment_119154586

Look at it this way - any improvement to the roof - whether that be replacement or repair - should improve the liveability of the room underneath through new insulation and such.