"New" fibreglass shed flat roof already leaking within 3 months

[lazer1235]

Hi Guys

So I had my shed/garage roof replaced 3 months ago. The guys who did it were to put bluntly, cowboys, who mugged me off and did a half hearted job and are now nowhere to be seen. i have tried to chase them up, but no luck. messages ignored and numbers changed i presume.

Anyway, i'm over trying to get my moneys worth and know that im going to have to sort this out alone, and im reluctant to get a professional in and fork out more money.

The new garage roof was apparently a fibreglass roof with wooden chipboards, but recent weather and cold temperatures has meant that rain has collected and pooled on top of my flat roof and the water is now seeping through and falling inside the garage. There is so much water on the flat roof that ducks & pigeons sometimes sit there!

Whenever i go into my garage i see damp wet patches on the concrete floor, where the beads of water are slowly dropping. (see pictures attached).

I am not sure if the beads are from condensation or if it is actual rainwater seeping through the chipboard.

Anyhow, could anyone advise me on what the best option would be to sort this?

I was thinking to get some cheap bitumen/plastic roofing sheets and just lay it over the existing roof? (top view of roof picture attached).

The roof also hasnt been installed with a slight gradient, which is why water is pooling ontop of the roof.

Im really in need of some help and willing to try research and try anything myself if someone could point me in the right direction.

Any suggestions are much appreciated


Thanks!

 

[KenGMac]

lazer1235, good evening.

The drips of water on the underside of the roof material look a lot like condensation, the general pattern of spread of the droplets tend to suggest this?

Can you introduce some cross flow of fresh air in other words ventilate. I am assuming that there is no heating in the area?

Do you by any chance use the area for a washing machine or tumble drier? both produce a load of free water that will form itself into condensation on any cold surface? the roofing material will be really cold in this weather we are having now, up here we did not get above + 3 degrees all day.

As for the ponding on the top surface? try venting the space before doing anything else, after all ventilation is a really cheap option??

Ken.

 

[HERTS P&D]

Did you ask for a pond??

Andy

 

[lazer1235]

lazer1235, good evening.

The drips of water on the underside of the roof material look a lot like condensation, the general pattern of spread of the droplets tend to suggest this?

Can you introduce some cross flow of fresh air in other words ventilate. I am assuming that there is no heating in the area?

Do you by any chance use the area for a washing machine or tumble drier? both produce a load of free water that will form itself into condensation on any cold surface? the roofing material will be really cold in this weather we are having now, up here we did not get above + 3 degrees all day.

As for the ponding on the top surface? try venting the space before doing anything else, after all ventilation is a really cheap option??

Ken.

Hi Ken

Thanks for that - that was my thought aswell, but im not entirely convinced it is condensation purely because of how much water is sitting on the roof?
with regards to ventilation, the garage is closed and there would be no way for me to introduce fresh air flow. The garage is mainly used as storage, and is a bit neglected. no electricity. the place is not water tight. there are cracks in walls and gaps between bricks where cements has broken away etc. so i presume air can get in and out that way.

i have attached another picture circling the main area of the ground that becomes damp.

and agreed, in the midlands the temperature has also been <3 degrees which is not helping!

 

[lazer1235]

Did you ask for a pond??

Andy

Oh good one!

 

[KenGMac]

lazer1235, good evening, again.

OK Understood, how about a few high and low air bricks in the available external walls?? will give a cross flow of air, but?? will make the area a lot colder ?

Ken.

 

[lazer1235]

@KenGMac thanks for the suggestion mate!

Adding a few air bricks may seem like a potential shout so i may look into this.

This may be a rash, reckless wildcard but how about painting the underside of the chipboard with an anti condensation paint like this from amazon

https://www.amazon.co.uk/dp/B0120YN41U/ref=cm_sw_r_cp_apa_fabc_PauZFbM5HGQ0M?_encoding=UTF8&psc=1

Cheers

 

[catlad]

Did they build the roof?

 

[datarebal]

You could get a professional in and do it properly?

The beads do look like condensation , the coolness caused by the ponding will agravate it.

Try attaching a strip of plastic tight to the underside between joists , keep your eye on it and see if it beads on the plastic

 

[catlad]

You could Jack the roof up in the middle a little to give you a dry area and see if this help stop the dripping in that area.

 

[JP_]

There shouldn't be any water pooling on the roof.
I'm not an expert, but looks like you might need to get it done again, with enough fall to ensure no water stands on the roof.
A flat roof should never be flat

 

[lazer1235]

You could get a professional in and do it properly?

The beads do look like condensation , the coolness caused by the ponding will agravate it.

Try attaching a strip of plastic tight to the underside between joists , keep your eye on it and see if it beads on the plastic

Ok thanks for this, good idea - if it beads on the plastic then its definitely condensation, what do you think of painting the underside with a anti condensation paint?

 

[lazer1235]

You could Jack the roof up in the middle a little to give you a dry area and see if this help stop the dripping in that area.

Thanks although i will need to research more about how to do this. The guys also didn't build the roof, they literally tore old felt off and the rotten boards and replaced them with new boards and fibreglass

 

[HERTS P&D]

They should of checked the roof for any 'fall' and if none then they should of fitted firring pieces,then reboarded.

Andy

 

[lazer1235]

There shouldn't be any water pooling on the roof.
I'm not an expert, but looks like you might need to get it done again, with enough fall to ensure no water stands on the roof.
A flat roof should never be flat

Not what i wanted to hear but this was always a thought in the back of my mind

With regards to water pooling, do you think i could create a "make shift" slant on top of the existing roof, with overlapping bitumen/plastic roofing sheets?