ᐅ Wall penetration – how to create a sealed cable passage – recommended methods and products?
Created on: 18 Sep 2025 12:14
B
Bicki89Dear community,
I am considering creating a wall opening on our balcony to install a cable pass-through. I need "holes" for electricity, internet (network cables), and possibly in the future for photovoltaic and additional lines related to an air conditioning system, which might be installed later. So, we are talking about roughly a dozen cables/hoses with a total diameter of about 10cm (4 inches).
My problem is as follows:
1. What exactly should I use as a cable pass-through so that I can later modify or add cables easily? I have attached a picture. Does such a product make sense, or do I need something different?
2. How do I ensure it is sealed properly? When tightening the screws, the black sealing rubber presses outward, right? Is that sufficient?
3. Depending on the wall thickness (which I do not know yet, as insulation is also applied), would I need one or two of these cable pass-throughs?
4. Do you have any other advice regarding the implementation?
I am inexperienced with this and I am still unsure whether to do it myself or hire a professional.
Does anyone have experience with this? Which trade would be responsible for the work (mason/bricklayer?), and what could it cost approximately?
Thank you very much in advance!
I am considering creating a wall opening on our balcony to install a cable pass-through. I need "holes" for electricity, internet (network cables), and possibly in the future for photovoltaic and additional lines related to an air conditioning system, which might be installed later. So, we are talking about roughly a dozen cables/hoses with a total diameter of about 10cm (4 inches).
My problem is as follows:
1. What exactly should I use as a cable pass-through so that I can later modify or add cables easily? I have attached a picture. Does such a product make sense, or do I need something different?
2. How do I ensure it is sealed properly? When tightening the screws, the black sealing rubber presses outward, right? Is that sufficient?
3. Depending on the wall thickness (which I do not know yet, as insulation is also applied), would I need one or two of these cable pass-throughs?
4. Do you have any other advice regarding the implementation?
I am inexperienced with this and I am still unsure whether to do it myself or hire a professional.
Does anyone have experience with this? Which trade would be responsible for the work (mason/bricklayer?), and what could it cost approximately?
Thank you very much in advance!
Hello,
this is called a Doyma seal, named after the manufacturer, but similar products are available from others as well. Each pipe is sealed individually, which creates a very tight seal, but it requires a lot of space, so these seals come in diameters up to 400 mm (16 inches). This can get seriously expensive. It is also technically quite overkill; these seals are intended for penetrations in basements with waterproof concrete structures. You need a clean core drill hole (500 euros) and the seal itself (300-1000 euros, depending on size and type). For an above-ground penetration, I would do it much more simply.
Make a hole in the wall, insert a 50-80 mm (2-3 inches) conduit, pull the cables through, and firmly stuff everything with glass wool (for sound, thermal, and fire protection!) and you’re done.
Best regards,
Andreas
this is called a Doyma seal, named after the manufacturer, but similar products are available from others as well. Each pipe is sealed individually, which creates a very tight seal, but it requires a lot of space, so these seals come in diameters up to 400 mm (16 inches). This can get seriously expensive. It is also technically quite overkill; these seals are intended for penetrations in basements with waterproof concrete structures. You need a clean core drill hole (500 euros) and the seal itself (300-1000 euros, depending on size and type). For an above-ground penetration, I would do it much more simply.
Make a hole in the wall, insert a 50-80 mm (2-3 inches) conduit, pull the cables through, and firmly stuff everything with glass wool (for sound, thermal, and fire protection!) and you’re done.
Best regards,
Andreas