Concrete slab against garage wall?

[zzr1200]

The garage doesn't appear to have a dpc in the wall, the internal floor is higher than outside concrete path.


Answer....Yes or No to remaining questions
1. Do you have or ever had a damp problem in the garage caused by the path?..........
2. You have stated there was weak concrete there before, which I presume is why you're replacing it??...........yes
3. Will installing a dpc around the patch make any difference to the rest of the building damp proofing???...............no
4. Is it worth installing a french drain for a 5ft patch in a path against a longer building????............. probably not
5. Provided the path repair doesn't cause any extra water pooling than before, will it make any difference?????..........no
6. Is it worth worrying about??????...........
7. Does it really matter???????..........

 

[Pete.]

If the existing slabs in the pic aren't causing any problems then why should your new slab? Put a membrane down, jam half a dozen dowels in so that it remains level relative to the adjacent slabs and pour it in. don't use too much water or over-tamp it and apply a brush finish.

 

[Pond frog]

Instead of concrete fill the space with some block paving, you’ll still get a flat surface you can sweep but it will be free draining

 

[Screwdriver]

I'd just fill it with a good strong concrete and strike the outline to promote cracks where you want them, around the edge of the slab.

The only other consideration might be to incorporate some super strong mounting points for ground anchor or to bolt a vice down to. Or a big thick slab of steel flush with the concrete you could use to weld/tack onto.

 

[Morrisman]

What is all the other concrete like? If that has no gap, then I’d not bother leaving a gap with the new concrete.

 

[angellonewolf]

I think your over thinking this a bit much

If there was cement there before and you had no problems just lay some new in there id pron put a bit of plastic dpc along the back just so the concrete does not attach its self to the wall but prob only if you got some

As all ready said before if you have had water standing there some block paving looks to be quite deep so dig a bit more out and add sand and wack down job done