For a while I've been more and more troubled by water flooding into the
garage, every time it rains particularly hard.

Its a concrete sectional job, with a slab concrete floor. The reason it
flows in, is that on one side the ground level rises from front towards
the rear, to about 3" higher than the base slab. The 'ground' is
actually where the drive continues past the side of the garage - 3x2
slabs, with the gap between slabs and garage filled in with concrete.

I dug the entire stretch of concrete alongside up, to a width of 6" to
expose the garage slap, since when I have painted slab and garage wall
to ground level with Tetraseal car body underseal applied liberally to
waterproof the entire length - so there is no gap for water to gain
entry.

I wasn't sure about using the Tetraseal, but I had plenty of it stored
up and it seemed to be bitumen based, so should work. Having flooded
the channel with water to test it, there was no sign of any ingress so
it at least looks promising.

I just need to decide now, what to refill the channel with - more
concrete, gravel with a thin topping of cement, or just loose gravel.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

In message , Harry
Bloomfield writes
For a while I've been more and more troubled by water flooding into the
garage, every time it rains particularly hard.

Its a concrete sectional job, with a slab concrete floor. The reason it
flows in, is that on one side the ground level rises from front towards
the rear, to about 3" higher than the base slab. The 'ground' is
actually where the drive continues past the side of the garage - 3x2
slabs, with the gap between slabs and garage filled in with concrete.

I dug the entire stretch of concrete alongside up, to a width of 6" to
expose the garage slap, since when I have painted slab and garage wall
to ground level with Tetraseal car body underseal applied liberally to
waterproof the entire length - so there is no gap for water to gain entry.

I wasn't sure about using the Tetraseal, but I had plenty of it stored
up and it seemed to be bitumen based, so should work. Having flooded
the channel with water to test it, there was no sign of any ingress so
it at least looks promising.

I just need to decide now, what to refill the channel with - more
concrete, gravel with a thin topping of cement, or just loose gravel.

Pea shingle.

To do the job properly you need an edging strip to retain the high
ground. 1m concrete edging strips with a blob of stiff mix concrete at
the ends and joins.


--
Tim Lamb

Tim Lamb wrote:
In message , Harry
Bloomfield writes
For a while I've been more and more troubled by water flooding into
the garage, every time it rains particularly hard.

Its a concrete sectional job, with a slab concrete floor. The reason
it flows in, is that on one side the ground level rises from front
towards the rear, to about 3" higher than the base slab. The 'ground'
is actually where the drive continues past the side of the garage -
3x2 slabs, with the gap between slabs and garage filled in with concrete.

I dug the entire stretch of concrete alongside up, to a width of 6" to
expose the garage slap, since when I have painted slab and garage wall
to ground level with Tetraseal car body underseal applied liberally to
waterproof the entire length - so there is no gap for water to gain
entry.

I wasn't sure about using the Tetraseal, but I had plenty of it stored
up and it seemed to be bitumen based, so should work. Having flooded
the channel with water to test it, there was no sign of any ingress so
it at least looks promising.

I just need to decide now, what to refill the channel with - more
concrete, gravel with a thin topping of cement, or just loose gravel.

Pea shingle.

To do the job properly you need an edging strip to retain the high
ground. 1m concrete edging strips with a blob of stiff mix concrete at
the ends and joins.


Put some of that agricultural pipe(the stuff with slots) in the trench
and run it away lowerdown.

On Sat, 14 Jun 2014 20:46:05 +0100, Tim Lamb wrote:

I just need to decide now, what to refill the channel with - more
concrete, gravel with a thin topping of cement, or just loose
gravel.

Pea shingle.

Aye, effectively create a french drain. I'd be tempted to use 20 mm
shingle, small stuff like pea shingle may well "migrate" from where
it's supposed to be. I'd also use eroded stuff, ie nice and rounded
as one would find on a shingle beach, not crushed stone or chippings.

To do the job properly you need an edging strip to retain the high
ground. 1m concrete edging strips with a blob of stiff mix concrete at
the ends and joins.

If the drive slabs where relying on the concrete fill and garage side
not to move, something a bit more substantial than that will be
required. Especially if the drive has vehicular traffic. 2 or 3 18"
lengths of rebar driven in per slab? (2 for narrow edge 3 for long
edge). These will be hidden by the shingle fill.

--
Cheers
Dave.