I am going to put up a hat rack on a wall made of aerated concrete. In one of the holes, the plug just spins around, so we've probably drilled a bit carelessly or hit a cavity? The remaining holes work perfectly. We've tried a wider screw but it doesn't help. I'm now considering if there's something we can spray into the hole that fills and hardens, so we can re-drill the hole. Has anyone had a similar problem?
What size have you drilled with? Fischer has two really good lightweight concrete plugs. One you screw in and the other you hammer into the wall.
1: Insert wall anchor compound into the hole, put in the plug, and wait until it hardens, then just screw in.
2: I think lightweight concrete screws without plugs work great, and you don't need to drill beforehand. The downside is that they might be a bit bulky/thick.
/LOB
2: I think lightweight concrete screws without plugs work great, and you don't need to drill beforehand. The downside is that they might be a bit bulky/thick.
/LOB
Fischer's plugs are good, otherwise the glue variant will probably work. In the worst case, or if you're going to attach something even heavier to really poor concrete, chemical anchors/fixative are recommended, but since it is usually difficult to reuse an opened tube, it is not something I would recommend as a first option for a single screw.
If the hole has become too large, you can advantageously use wood shavings specifically on lightweight concrete. Think of larger matchsticks placed on either side (above/below) of the screw. The screw should have the largest possible thread.
There are screws you can screw directly into the concrete without pre-drilling, you don't use any plugs at all. This works really well. Available at e.g. Clas Ohlson with item number 40-9572. Best regards, Kenny
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· Västernorrland
· 12 029 posts
How long is the plug? It works very poorly with short plugs in porous materials. It is better with really long ones like nail plugs that can be 10-15cm (depending on the wall thickness of course). The installation becomes much more stable and stays in place.
If the hole has become very large and not round, you can use fischer gb8, works great.
The mistake many make when drilling in lättbetong is using the hammer function on the drill because it is "stone." Lättbetong is soft and should be drilled without the hammer function, otherwise the hole will be too large.
Lightweight concrete?
Well, then it's just a matter of tearing down the house and rebuilding with sensible materials.
Do I hate lightweight concrete? Absolutely ...
It's a really difficult material, completely hopeless to fasten into. You've received a lot of good tips. I've used these sometime when putting up something that needs to hold better than an electrical cable.
SCHNEIDER ELECTRIC TPH Plug 6x50 Screw 5pcs
https://www.storel.se/sto/Produktkatalog/Installationsmaterial-(11-15,-17,-18)/15---Fästmaterial/Plugg/Lättbetong/TPH-Plugg-6x50-Skr-5st/p/1507149?prevPageNumber=0
Regardless of what you choose to fasten with, you have to be extremely careful and meticulous in lightweight concrete, really don't drill any holes even a fraction of a mm too large, etc. I usually try with 1/2 or 1 mm smaller holes first.
Well, then it's just a matter of tearing down the house and rebuilding with sensible materials.
Do I hate lightweight concrete? Absolutely ...
It's a really difficult material, completely hopeless to fasten into. You've received a lot of good tips. I've used these sometime when putting up something that needs to hold better than an electrical cable.
SCHNEIDER ELECTRIC TPH Plug 6x50 Screw 5pcs
https://www.storel.se/sto/Produktkatalog/Installationsmaterial-(11-15,-17,-18)/15---Fästmaterial/Plugg/Lättbetong/TPH-Plugg-6x50-Skr-5st/p/1507149?prevPageNumber=0
Regardless of what you choose to fasten with, you have to be extremely careful and meticulous in lightweight concrete, really don't drill any holes even a fraction of a mm too large, etc. I usually try with 1/2 or 1 mm smaller holes first.
I can also mention that what many recommend is based on the products they encounter in their profession, what I suggested is Schneider's, i.e., the range that we electricians are often surrounded by. A plumber has other things in their experience backpack. It's not easy to know what is best, only that I and he have each found a solution that works for us.
Fischer SX in combination with screws corresponding to the largest recommended diameter on the packaging have never given me any problems.
I find lightweight concrete quite pleasant to work with. When I worked as an electrician, I had a Bost PH1 screwdriver where the insulation was stripped to a length corresponding to the plug. I hammered it in, and voila, a perfect hole for the plug (Thorsmans yellow/red)
I find lightweight concrete quite pleasant to work with. When I worked as an electrician, I had a Bost PH1 screwdriver where the insulation was stripped to a length corresponding to the plug. I hammered it in, and voila, a perfect hole for the plug
(Thorsmans yellow/red)
Heh.... I do the same. An old junk screwdriver from ÖoB marked on the handle. Exactly right for red thorsmanplugg
For heavier stuff, it's Fisher GB or Tox Ytox, they stick like a rock.
Overall, I like lättbetong, except for the radon.
For heavier stuff, it's Fisher GB or Tox Ytox, they stick like a rock.
Overall, I like lättbetong, except for the radon.
Hello!
I live in a light concrete house and have just installed a heavy patio door using Essve's triangular light concrete plug. Never doing that again. Terrible plug.
Had to redo it and fill the holes with mortar and redo it, despite nice smaller holes. The plug doesn’t like being inserted and removed. Tomorrow the next door is going up so fixed a few other things...
My tip is either a metal light concrete anchor or a special plug with wings as shown in the image.
The plug with wings is available at Bauhaus from Stabilt, and 4 pieces cost around 35kr compared to Fisher’s counterpart, which costs 90kr.
The light concrete anchor is from FAST, purchased from Velltra, costing 90kr for 40 pieces.
Quite a price difference.
I did a test, inserted these into the wall, and screwed in and out without torque back and forth.
The plug with wings almost cracked the wall, it sets so intensely.
Then I tried using pliers to pull with all my might. After much effort, I managed to remove the light concrete anchor, but it was incredible how hard I had to pull.
The plug with wings is still there; it's impossible to remove.
Essve's light concrete plug is easy to remove despite a small neat hole.
The advantage of the light concrete anchor is that you can place the plug more precisely where you want it. Not as easy with the plug with wings, which tends to pull on itself due to the resistance when inserting it into the hole. The anchor doesn't move in the hole like the plug with wings, even though you can never remove the plug. But it allows for some movement. Note: I had screwed it back and forth to the bottom without torque, almost cracking the wall, which of course affected it. But the anchor wasn’t affected the same way despite the same procedure.
Thus, I will continue using the anchors instead, significantly cheaper and worked great.
If it's really heavy stuff, a combo with a plug with wings and an anchor might be good.
Tomorrow it’ll be a combo. I also fill the holes with tube cement before inserting the plug/anchor.
For putting up shelving systems and the like, it will be anchors going forward. Heavy glass doors, sliding sections, etc., a combo is preferable.
I live in a light concrete house and have just installed a heavy patio door using Essve's triangular light concrete plug. Never doing that again. Terrible plug.
Had to redo it and fill the holes with mortar and redo it, despite nice smaller holes. The plug doesn’t like being inserted and removed. Tomorrow the next door is going up so fixed a few other things...
My tip is either a metal light concrete anchor or a special plug with wings as shown in the image.
The plug with wings is available at Bauhaus from Stabilt, and 4 pieces cost around 35kr compared to Fisher’s counterpart, which costs 90kr.
The light concrete anchor is from FAST, purchased from Velltra, costing 90kr for 40 pieces.
Quite a price difference.
I did a test, inserted these into the wall, and screwed in and out without torque back and forth.
The plug with wings almost cracked the wall, it sets so intensely.
Then I tried using pliers to pull with all my might. After much effort, I managed to remove the light concrete anchor, but it was incredible how hard I had to pull.
The plug with wings is still there; it's impossible to remove.
Essve's light concrete plug is easy to remove despite a small neat hole.
The advantage of the light concrete anchor is that you can place the plug more precisely where you want it. Not as easy with the plug with wings, which tends to pull on itself due to the resistance when inserting it into the hole. The anchor doesn't move in the hole like the plug with wings, even though you can never remove the plug. But it allows for some movement. Note: I had screwed it back and forth to the bottom without torque, almost cracking the wall, which of course affected it. But the anchor wasn’t affected the same way despite the same procedure.
Thus, I will continue using the anchors instead, significantly cheaper and worked great.
If it's really heavy stuff, a combo with a plug with wings and an anchor might be good.
Tomorrow it’ll be a combo. I also fill the holes with tube cement before inserting the plug/anchor.
For putting up shelving systems and the like, it will be anchors going forward. Heavy glass doors, sliding sections, etc., a combo is preferable.
