Concrete Garage - Self Leveling?

[UncleUncleMatthew]

Hi DIY Crew!

A new 15cm concrete base + prefab sectional garage will be built soon in my back yard. It's a 5.61 x 5.56 m double garage.

Base is going to be raised over the garden terrain, thus water should relatively stay away from the actual garage floor.

However, I understood that concrete panels will be layed down over the concrete slab. Then I should go around internally and create a small lip around with mortar in order to stop any chance of water coming into.

I was looking at possibile long term solution for this issues. My Thoughts:

- firstly, use external sealing between base and concrete walls with some high-end mastice/hybrid sealant.
- a 5/10mm of self leveling coupound ( https://www.screwfix.com/p/no-nonsense-floor-levelling-compound-20kg/453hu ) in order to fill the gap between concrete panels and concrete slab
- Lastly, some rubberised paintable membrane on the external areas to ultimate the sealing process.

At the moment I'm looking for some advice and if someone can explain me a bit about the SBR+ priming process for the self leveling screed. Tried to find some information online, however, I found some mixed results.

Thanks!

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[^woody^]

Polymer mastic, epdm gasket between the panels and the slab when they are erected, not messing about trying to seal them afterwards.

 

[UncleUncleMatthew]

Polymer mastic, epdm gasket between the panels and the slab when they are erected, not messing about trying to seal them afterwards.

I do not think they will put anything between the concrete prefab wall and the concrete slab. I have asked if they will somehow "seal/glue" them aswell, and they answered back saying "no we will put the on the concrete slab since we do not want the wall slips and falls". I forgot to ask them if they are going to somehow use some mastic on the outside perimiter. Anyway, they told me, I'm gonna need to create a mortar lip inside to prevent water coming in. However, in my personal opinion, the mortar will be fine at the beginning, but then it will crack.

 

[^woody^]

I would suggest that it's up to the customer to dictate what they want, not the contractor.

It's nonsense for whoever is building this or anything to say, "We are going to build it, but it won't be waterproof, so that's up to you to sort out and it's nothing to do with us"!

The fact is, sectional garages will move, and you want a flexible joint, not a rigid one. There are lots of threads on here about this very thing and trying to seal the joint afterwards, but you have the perfect time now to create the best seal while the thing is being built.

 

[noseall]

the mortar will be fine at the beginning, but then it will crack.

Always fails.