Ok, it seems reasonable that the holes are 3/8, if the pipe is 8", based on the picture. I will use a 9mm drill to drill the holes. If that is sufficiently small to allow bridging, then it should work for the pipe. 100mm = 3.94" ~= 4". A 4" pipe carries 1/4 the flow at the same speed, so 1/4 the...
Hi Oldestguy, thanks for your comments! And of course thanks for your input in the other threads you have given input to, which were the foundation to part to my decision to use the concrete sand.
To answer your questions:
1) Is the ground surface outside the house the same as the ground...
One more thing: a picture of the area just down from the problem heat pump unit. Note the moss going up several bricks. It seems reasonable to think that the source of the problem is water wicking up the bricks. Previously, the water was going from the heat pump, and landing between the support...
BTW I measured the drains. Mostly 21-22cm wide, 60cm deep in deepest parts, 45-50cm in most places, 30cm on the non-problem side, but penetrating the clay layer by maybe 5cm.
I have considered buying a dehumidifier and sticking it down there, with a permanent drain going outside. It may be...
The highest elevation side.
The problem side (upper). Not that the lower border of the local depression is at the fence line approximately.
The problem heat pump: tilted now.
Problem heat pump: rear. I think I will wait for good weather, turn the heat pump off, pressure spray the moss off...
Hi,
I have been lurking on this forum for a while, reading oldestguy's posts advocating the use of ASTM C33 concrete sand for French Drains.
I live in Australia, in a single brick house on stumps, no basement. During a particularly wet winter (ground doesn't freeze here), we were getting a...