Advice on water proofing please

SexyGreyFox · 10 Jul 2025 at 15:41

For decades my garage has looked like a swimming pool when it rained but recently we've had a new roof which has solved the problem.
However on the floor in the corners a bit of damp comes through because the garden the other side is right up to it and a little bit higher and I'd like to put something down to stop it.
What's the best stuff to put in those corners with a trowel please?

Haggisman · 10 Jul 2025 at 16:01

Sounds like you need some "tanking slurry", I haven't used it before, but currently working on a similar issue in our shed which I'm converting to a workshop

Mason- · 10 Jul 2025 at 16:46

SexyGreyFox said:
because the garden the other side is right up to it and a little bit higher

Waterproofing it isn't really a good solution. If the moisture can't get out on your side, it'll stay in the bricks, and in winter with it freezing/defrosting it will spall the bricks, and worse over time. Really the best thing would be for the ground level to be lowered. Or drainage put there.

And if your attitude is "It's a garage I'm not that worried about doing a proper solution", then why bother doing anything.

SexyGreyFox · 10 Jul 2025 at 16:56

Mason- said:
Waterproofing it isn't really a good solution. If the moisture can't get out on your side, it'll stay in the bricks, and in winter with it freezing/defrosting it will spall the bricks, and worse over time. Really the best thing would be for the ground level to be lowered. Or drainage put there.

And if your attitude is "It's a garage I'm not that worried about doing a proper solution", then why bother doing anything.

Asking the neighbours to lower their garden by 2" is not an option.
It's been like that since 1983 when we moved in and I'll be dead within 10 years probably, if not sooner.
Quick fix is what I want.

Mason- · 10 Jul 2025 at 17:02

SexyGreyFox said:
Asking the neighbours to lower their garden by 2" is not an option.
It's been like that since 1983 when we moved in and I'll be dead within 10 years probably, if not sooner.
Quick fix is what I want.

I'd leave it then personally. Like I said, putting something on it to stop it coming into the garage will just trap it in the walls and do more harm than good.

Thekwango · 10 Jul 2025 at 17:06

SexyGreyFox said:
It's been like that since 1983 when we moved in and I'll be dead within 10 years probably, if not sooner.

so just leave it be in that case.

SexyGreyFox said:
Quick fix is what I want.

there isn't really a quick fix for your issue.

SexyGreyFox · 10 Jul 2025 at 17:12

Mason- said:
I'd leave it then personally. Like I said, putting something on it to stop it coming into the garage will just trap it in the walls and do more harm than good.

They are not walls, they are 2" (at the most) panels.

200sols · 10 Jul 2025 at 17:28

Move house.

SexyGreyFox · 10 Jul 2025 at 18:01

200sols said:
Move house.

It is the way, to Droitwich

radderfire · 10 Jul 2025 at 18:29

Maybe some sort of sealant spray would do it.

SexyGreyFox · 10 Jul 2025 at 18:43

radderfire said:
Maybe some sort of sealant spray would do it.

I quite like Haggismans suggestion.

radderfire · 10 Jul 2025 at 19:00

As others have said, if you do seal it, you might have more issues with damp in the wall.

If it's just visual you're bothered about, you could just get some sort of floor mats (that have ventilation holes), so you couldn't see it.

radderfire · 10 Jul 2025 at 19:01

Or you could try and install a damp proof course / membrane.

SPArton · 10 Jul 2025 at 20:14

What is behind the wall?

SexyGreyFox · 10 Jul 2025 at 20:24

SPArton said:
What is behind the wall?

It's not a wall, it's a 2" thick block of reinforced concrete and the other side is my neighbours lawn.

LuckyBenski · 10 Jul 2025 at 20:58

Just make sure the garage gets a bit of ventilation and it will probably not be too bad. I've spent a lot of time worrying about unsealed garage floors when ultimately it was fine unless I trapped the moisture by putting stuff on top.

Haggisman · 11 Jul 2025 at 09:10

radderfire said:
Or you could try and install a damp proof course / membrane.

That would have the same effect as tanking slurry, surely?

radderfire said:
As others have said, if you do seal it, you might have more issues with damp in the wall.

If it's just visual you're bothered about, you could just get some sort of floor mats (that have ventilation holes), so you couldn't see it.

The wall is going to be damp whether it's sealed or not - yes the correct thing to do is "fix" the damp in the first place - i.e. a DPM on the outside, but it sounds like that isn't a practical solution!

The Angry Welshman · 11 Jul 2025 at 09:33

SexyGreyFox said:
It's not a wall, it's a 2" thick block of reinforced concrete and the other side is my neighbours lawn.

My parents had this with their back shed and neighbours garden. We spoke to the neighbour they allowed us to dig down along the wall of the shed in the garden. Add a liquid membrane to the wall over a few days then filled with gravel, added visqueen and then re-top soiled. Never had damp since and that was 40yrs ago

SexyGreyFox · 11 Jul 2025 at 12:05

Just took a picture and only realised after 42 years that it is on concrete the other side and his lawn runs up to the concrete so basically it's just badly fitted concrete slab garage walls that aren't located correctly on the ground.
Bloke over the road has give me something to try.

FISHGUTS · 12 Jul 2025 at 08:51

You need kA tanking slurry. Used it many a time for that same purpose. It's a fantastic product. All builders merchants stock it