Concrete roof - Do I need acrow props?

[mrmadhat]

I have an outhouse that is currently seperated into 3 seperate spaces (storage/coal cupboard/toilet) it's brick built with a concrete roof. I want to remove the internal walls to create an open space and make use of it in some way.

My dad was concerned that it might be load bearing so I asked a builder who's done work on my house to come and take a look. He told me to take a brick out miss one then take another out so he could see. He came round and said it was re-enforced concrete and I needn't worry. So I went ahead and took out some more bricks.

Feeling pleased with myself (I've never really done DIY before) I took a picture and put it on fb next my dad is warning me again about it possibly coming down whilst I'm working under it. This is worrying me for obvious reasons so I'm thinking maybe I should use some acrows to support it just incase.

I'm wondering if anyone has any advice, should I use acrows (or something similar) or not?

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• mrmadhat
• 19 Sep 2018

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• mrmadhat
• 19 Sep 2018

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• mrmadhat
• 19 Sep 2018

 

[bobasd]

if thats a single monoslab with wire or rebar in it thers no problem.
these slabs were usuly cast in one piece.
but i cant see if thers a join above the dividin wall - probly not.
follow the shutterin board marks an see if they run through from one side of the wall to the other.

to be safe, just openup below the openin youve made. go down to the floor. an leave it like that for a few weeks to see if any cracks appear.

its not an old air raid shelter is it?

 

[^woody^]

I'd stake my reputation as a top belly dancer on it being OK

 

[geraldthehamster]

If it needed acrows while you were working under it, it would need support when it was finished, wouldn't it?

 

[stuart45]

Not if you get out quick.

 

[honda]

The son- in- law of a friend of mine was killed a few years ago doing this when one of the perimeter walls collapsed due to the extra weight on it when the interior wall was in the process of being removed. That isn't to say yours will but what I am saying is be very careful. Please get further advice.

 

[mrmadhat]

Thanks for the responses everyone I'm finding the advice very helpful.

The son- in- law of a friend of mine was killed a few years ago doing this when one of the perimeter walls collapsed due to the extra weight on it

I think based on this alone it would be good to prop it during removal and put some permanent support in going forward.

If it needed acrows while you were working under it, it would need support when it was finished, wouldn't it?

A thought was to build two brick posts to the left and right of where the wall currently is and use that to rest a lintel on. Would this be a good approach?

I agree with getting more advice the problem I'm finding with builders is they look and say "yeah it'll be reet that" but don't give the reasoning behind why they believe that. I asked the one the other day and he just said through experience which I appreciate but still.

 

[Nige F]

its not an old air raid shelter is it?

Council House shed from the 30's - 50's

 

[Nige F]

I have an outhouse that is 3 spaces (storage/coal cupboard/toilet) . I want to remove the internal walls and make use of it in some way.

A really big toilet ?

 

[endecotp]

I'm finding with builders is they look and say "yeah it'll be reet that"

Statisticians would call that “survivor bias”.

 

[flameport]

If there is doubt about the existing roof, you could remove all of it and replace with a timber structure.

 

[Calvr1ch1]

Sorry for the question on an old post but how did you get on as I am currently looking at the same sort of job to do on out outhouse.

 

[Keithmac]

Someone in our area got crushed to death under one of those as well so just be careful when you're knocking bricks out!.

 

[Nige F]

if that' s a single mono slab with wire or rebar in it there is no problem.
these slabs were usually cast in one piece.
but i cant see if there is a join above the dividing wall - probably not.
follow the shuttering board marks an see if they run through from one side of the wall to the other.

to be safe, just open up below the opening you've made. go down to the floor. an leave it like that for a few weeks to see if any cracks appear.

its not an old air raid shelter is it?

There you go bobasd/ tell80 I've edited your useless spelling for you