This is not fun 
Old-fashioned concrete block in the foundation. When drilling, you often end up in a cavity of random shape after a few cm depth. Or on the edge of a cavity so that the drill goes crooked.
If you want to use a plug to screw something in, the usual methods aren't effective.
Any tips?
Old-fashioned concrete block in the foundation. When drilling, you often end up in a cavity of random shape after a few cm depth. Or on the edge of a cavity so that the drill goes crooked.
If you want to use a plug to screw something in, the usual methods aren't effective.
Any tips?
What are you going to hang up?
How many attachment points?
Over how large an area are the attachment points?
How much weight?
How far out from the wall will the center of gravity be?
Our fjärrvärmecentral has been hanging up with four screws & plugs in concrete hollow blocks, hung for 13 years without any issues.
How many attachment points?
Over how large an area are the attachment points?
How much weight?
How far out from the wall will the center of gravity be?
Our fjärrvärmecentral has been hanging up with four screws & plugs in concrete hollow blocks, hung for 13 years without any issues.
I have written this to many others here in the forum, so I might as well repeat it again. Nail plugs work great in concrete block. Of course, there can't be large "cavities" in the wall, because then nothing will support it. You might have to chip away the surface to the cavity and fill it with new concrete/husfix/cement/strong render. The advantage of nail plugs is that you don’t have any rotating movements against the hole wall since it expands radially outward and thus doesn’t "grind" the hole any more. Adjust the size of the nail plug to your needs. For example, I used 10 cm long nail plugs for the hat rack that had fallen down 3 times when using regular plugs. Now it has stayed up for two years so far... Before, when grandma came over with her coat filled with 10,000 items in the pockets, the hat rack inexplicably fell down..
When the installer was mounting the outdoor unit of our Air-To-Air heat pump on the exterior of our basement wall made of concrete hollow blocks, he made holes about 3 cm wide in which he knocked in wooden dowels. Then he drilled holes in the wooden dowels for the brackets. He claimed that this method always worked, and it has been holding up for 6-7 years now without any issues.
Most concrete hollow blocks have 2-3 "levels" with holes, so if you drill through the outer shell and at least one partition as well (which is maybe situated 7-8 cm in?), allowing the dowel to get support in more places than just the outer shell, I guess it holds up for the most part.
Most concrete hollow blocks have 2-3 "levels" with holes, so if you drill through the outer shell and at least one partition as well (which is maybe situated 7-8 cm in?), allowing the dowel to get support in more places than just the outer shell, I guess it holds up for the most part.
If there are large cavities and you hit right in them, there are plenty of options for sheet material that provide support behind the sheet. Otherwise, I would have used a chemical anchor and hoped to fill the hole.