External concrete wall garage - how to fill gaps

muvvvalac

Hi all
Very good morning
I have a detached garage with concrete walls, 50 years old. Water leaking from outside to inside on the ground and damaging flooring of garage. There was some plaster at the joint of floor and wall, through which water is coming and that plaster is damaged all around.
My questions:
I hope I need to replaster the edges inside/outside. Is ready made plaster available for exterior usage
Also are there any filler tubes kind of which I can fill with plaster then I can use that as this needs to be done all aorund the garage inside and outside

Thanks for your help

TELLIT01

Expanding filler would seem to be a potential solution.  It will take quite a bit and won't be cheap but it is flexible and should stay in place in the long term.  It can be sanded level and painted once it dries.

stuart45

It looks more like a sharp sand/cement fillet, put on with a trowel, and finished with a pointing trowel.

Jonesya

Don't use plaster because plaster isn't water proof, it will soak up water and fall apart. You probably mean mortar.

How is the water getting it? It looks like the joints on the outside are not sealed, so it could be getting in through the gaps between the panels and running down, and between the panels and the concrete bade. I'd try sealing all of those gaps before breaking out and replacing the concrete or mortar joints.

With the garage made from panels and posts bolted together so I'd expect there could be some movement, so I wouldn't use mortar for sealing those small gaps, I'd use an outdoor sealant - low modulus silicone or something similar. You can get them in colour which will match the panels.

I'd certainly seal the joints on the outside to stop the water getting in but I don't think I would seal the inside because if water does get into those joints between the panels then I'd want it to dry out, rather than trapping it in the void.

I'd try sealing the joints between the panels and the base, and the vertical joints, see what difference that makes before breaking out and replacing the mortar.

I'd use one of these, for example:

https://www.toolstation.com/everbuild-silicone-825-380ml/p93228

https://www.screwfix.com/p/sika-sikaflex-ebt-all-weather-sealant-beige-300ml/32710

muvvvalac

Jonesya said:

Don't use plaster because plaster isn't water proof, it will soak up water and fall apart. You probably mean mortar.

How is the water getting it? It looks like the joints on the outside are not sealed, so it could be getting in through the gaps between the panels and running down, and between the panels and the concrete bade. I'd try sealing all of those gaps before breaking out and replacing the concrete or mortar joints.

With the garage made from panels and posts bolted together so I'd expect there could be some movement, so I wouldn't use mortar for sealing those small gaps, I'd use an outdoor sealant - low modulus silicone or something similar. You can get them in colour which will match the panels.

I'd certainly seal the joints on the outside to stop the water getting in but I don't think I would seal the inside because if water does get into those joints between the panels then I'd want it to dry out, rather than trapping it in the void.

I'd try sealing the joints between the panels and the base, and the vertical joints, see what difference that makes before breaking out and replacing the mortar.

I'd use one of these, for example:

https://www.toolstation.com/everbuild-silicone-825-380ml/p93228

https://www.screwfix.com/p/sika-sikaflex-ebt-all-weather-sealant-beige-300ml/32710

Jonesya, thanks for your detailed reply. Thanks for correcting, ok it should be mortar and not plaster. I never do DIY but during lockdown, got some time so trying to fix my self
The water is leaking through gap between base and concrete panel wall and entering inside.
are you saying to use below to seal the gap along the edges on outside
https://www.toolstation.com/everbuild-silicone-825-380ml/p93228
https://www.screwfix.com/p/sika-sikaflex-ebt-all-weather-sealant-beige-300ml/32710
but not to fill the gap throughout the outside ede with mortar ?
what about inside edges, currently inside edges are covered with mortar but damaged at many places
really appreciate your reply

stuart45

This is a really common problem with these garages, especially as the slab often forms a toe outside to gather the water. Would be better if the slab sloped away a bit from the walls. I've heard that someone used a coat of Evercryl at the base externally, although it's not cheap.

fenwick458

what are you hoping to achieve here? It's a prefab garage, thats as dry as they are. if you wan't it completely watertight, knock it it down & rebuild it and then get it rendered.

muvvvalac

fenwick458 said:

what are you hoping to achieve here? It's a prefab garage, thats as dry as they are. if you wan't it completely watertight, knock it it down & rebuild it and then get it rendered.

I would like to fix the gaps so water does not get inside garage hence trying to find right solutions

muvvvalac

stuart45 said:

This is a really common problem with these garages, especially as the slab often forms a toe outside to gather the water. Would be better if the slab sloped away a bit from the walls. I've heard that someone used a coat of Evercryl at the base externally, although it's not cheap.

I got evercryl based on your note, have used it and now waiting for rain but I am very confident it worked. Thanks for your note

Chickereeeee

It may be too late, but for sealing the gaps use 'foam backer rod'. Its quite cheap and saves using loads of filler. Just choose the right size to squeeze it into the gap (It compresses to about 50% or more). Leave a cm or so in the gap for waterproof filler, if needed.

https://www.dortechdirect.co.uk/backer-rod.html

muvvvalac

Chickereeeee said:

It may be too late, but for sealing the gaps use 'foam backer rod'. Its quite cheap and saves using loads of filler. Just choose the right size to squeeze it into the gap (It compresses to about 50% or more). Leave a cm or so in the gap for waterproof filler, if needed.

https://www.dortechdirect.co.uk/backer-rod.html

you mean, I can buy https://www.dortechdirect.co.uk/grey-polyethylene-foam-backer-rod-40mm.html or the right size and cut into small cylinders and place it in the gaps

WONDERFUL
what is waterproof filler that you mentioned ? do I need that?
Thanks lot for your reply