Damp Patch On Garage Floor

[dilalio]

to know if it would be strong enough to show up.

Well I have used it to trace roof leaks.
Various colours on bunded-off areas of flat roofs!
Once had an exterior CWSC that we were able to use for the water. Idiot apprentice didn't use the "dye-free bucket" I'd set aside!
Office workers were showering in red water for about 3 weeks! It was like a scene from Carrie! Lol.

It can't hurt to try... Personally, I'd get the fluorescent green one.

May well be that the drain slots in the door are the source! Remember, they disperse water/moisture from higher up... Not from floor level... Try your hose at the top of the door and frame but not full bore... Spray it like rain and let it run down the wall as natural as you can.

Or put a different colour dye in a sprayer and use that!

 

[securespark]

Thanks. But what I don't understand is this has only been going on the last couple of weeks.

We've had the house since June 1999 and this is the first time any damp has appeared in that concrete floor.

But I will shower the door and see what happens.

I will use dye in the drains and see what happens.

I will lift a flag outside next to the gully to see if it is leaking.

In any case, regardless of the issue, I think I will have to improve upon that gully situation as there are too many pipes and they are not actually going into the gully, therefore water sometimes flows over the path.

I have briefly searched for something bigger than what I have, but couldn't seem to find anything suitable. Then again, I'm not a plumber/ builder and don't know what I'm looking for.

Also, it's not a split gully, is it? Our drainage system here has the sewage going to the back of the house and the rainwater to the front. Originally, the RHS of the gully was used for the downpipe and the left for the sink. Then things got a bit messed up when other stuff was added.

Another downpipe was added for the flat roof on the garage extension.
A waste pipe was added for a dishwasher.
And when we had a new boiler, it was moved to the garage and a condensate pipe was added.

 

[dilalio]

Is the water table high where you live?
Might have changed recently and pushed damp up! My dad's close has that issue... Houses built on what used to be swampy area.

 

[ShowerWoe]

Does this video help ?

 

[dilalio]

Does this video help ?

No.

 

[Harry Bloomfield]

Does this video help ?

Not at all, there is no condensation in the present high summer temperatures in the UK.