Integrity of concrete roof to outbuilding

[redfred85]

Hi, I have a brick outbuilding with a concrete roof. Circa. 5x3 meters.

The external surface is coarse and weathered and water has gradually been making its way inside.

I am concerned about its integrity, although it does seem solid at the same time.

I have no experience with these roof types so don't know if this is typical of their condition.

I have had a roofer take a look and he advised to batten with sloping firrings, board with OSB and apply a GRP finish.

Two questions:
1. Does a GRP roof seem a good way forward?

2. Is the internal condition typical and likely to be sound?

Many thanks.
RED

 

[^woody^]

Just recover the surface of the concrete if it needs doing. No need to batten or board it.

 

[JohnD]

putting a slope on it will shed water and prevent ponding.

OOI, how thick are the walls, and the roof slab? How old is your house?

The walls look wet so check the guttering.

 

[redfred85]

Hi JohnD, The house is circa 1920 but the shed was build after that, not too sure when.

The walls are a double skin and the internal skin is good, roof slab is about 6".

Guttering is useless as the drip edge has broken away and water just tracks back to the walls.

I will also be getting it re-rendered.


What would you recover it with Woody?


Thanks,
RED

 

[JohnD]

The walls are a double skin and the internal skin is good, roof slab is about 6".

solid walls? Or cavity?

it may have been an air-raid shelter. Age is a possible match.

13" wall can be shelter bond.

compare the roof

 

[^woody^]

it may have been an air-raid shelter. Age is a possible match.

Its a shed. There are 1000's like it up and down the country

 

[JohnD]

yes, and thousands of old shelters, too.

Which of them usually has a six-inch thick concrete roof?