Seal base of wall on prefab concrete garage

[Ouch77]

One of my 'side' projects is to sort out the moisture problem in my garage.

It's a concrete sectional garage on a concrete base, at some point recentlyish it's had a new steel roof, the old one was corrugated concrete (possibly with asbestos?), no idea how old it is, but it's on the title deeds so I guess something has been therer since the 80's. I've done nothing to it since taking possession.

It appears that either through neglect or age, there is no seal to speak of between the bottom of the wall panels and the concrete base, this means that in several locations water gets in under the walls and soaks the contents.

How can I stop this? Silicone sealant? tar? concrete? Chewing gum? I can't afford to dismantle the garage, and external access on one side is tricky as it's about a foot from a boundary wall (nice one that!).

Cheers!

 

[noseall]

I haven't counted them all but there are currently about a trillion posts on this subject, specifically relating to your problem.

Hit the search facility with some appropriate words.

 

[Ouch77]

I haven't counted them all but there are currently about a trillion posts on this subject, specifically relating to your problem.

Hit the search facility with some appropriate words.

"prefab" "Concrete" "garage" "wall" "Seal"

Tried that already, hence I posted.

Perhaps you could suggest other appropriate words that yield a trillion posts on this subject, cos I'm drawing a blank..

 

[noseall]

Ok, so I may have exaggerated a wee bit.

I personally have written about the problems associated with building a structure off a slab and whereby that slab protrudes beyond the footprint of the building - thus ensuring rain-water will collect on this 'toe'.

It is a common problem and a design fault.

The thing is concrete sectional garages are a low end budget affair with the base being no different. Installers say a fillet of mortar will suffice in keeping seepage at bay. What they don't tell you is that the garage will move or flex with temperature changes etc and the mortar will inevitably fail.

 

[Norcon]

Precast sections are always a problem when it comes to sealing.
Would not take the gift of them.
Just got word today that the pre cast walling on a 10million pound anerobic digestor has failed releasing the dangerous effluent by products.

We convinced a client last year not to use precast sections for his 240m stretch of 3m tall walling. It was 50/50 at one stage then I took him to 60/40 with some wise words and the pre cast guy got the shove.
We did the job with peri formwork and 40n pump mix.
Boy was he glad he listened to us.
This was a snapshot I took part way through the project...
http://tinyurl.com/m5vkmvf

Another happy customer.

 

[Ouch77]

Noseall- the toe in question is fairly generous- I suspect the size of the slab was rounded up to the nearest foot, and there's no sign of a gradient away from the wall either..

So based on the thinking that I don't have the time, money or wifely goodwill to demolish the garage and start again, how can I make the best of a bad thing, and stop/reduce the leaking?

Would a flexible sealant do? what would stick to (probably damp) concrete the best?

As an aside it looks like the floor of the garage is a bit like a relief map of Tibet, it's all one pour by the looks of things, but it isn't particularly smooth.
Could I fix both the leaking and the floor in one hit with a 20mm concrete screed, or is that asking for trouble?

 

[mdj1]

Did you ever find a solution to this?

 

[theprinceofdarkness]

You will have a problem getting a 20mm screed to stick. One good way is to paint th 6" up the wall and the edge of the base with SRB reinforced with cement. Three coats should do if u are talking about hairline cracks, else a SBR based mortar fillet. If you use a fillet then shelves etc will not stand up close to the wall without cutting their bases/legs to cope with the fillet.
Frank

 

[Ouch77]

Did you ever find a solution to this?

Kinda

On close examination of the joint between the wall and the floor, the small 5-10mm gap had the remains of some decaying mastic in there. I got as much of this out as possible, cleaned out the gap with compressed air, and then filled it with bitumastic mastic - the sort of stuff you'd use for roofing felt.

I then tanked the whole area with an obscene amount of car body shutz, essentially a gloopy black bitumen paint. This has controlled the seepage from most areas except where an ill placed shed has spoilt access, and the side access door which has a rotten lower frame. The seepage in these area's is much reduced and now subject to prevailed wind and rain, rather than continuous.

I can see this being a seasonal job, with occasional over-painting required to keep things waterproof, but at least it now feels manageable.

 

[Burnerman]

In the future, have a look at Evercryl from MKM.......it has glass fibres in it and it can be used as a flashing filler.
Good stuff!
John