Hello everyone,
I am facing the following issue:
Two years ago, I started renovating our detached flat-roof garage (concrete ceiling, masonry walls). The concrete ceiling extends on one side beyond the garage wall to cover the passage between the garage and the house.
The main problem was that the old waterproofing, which had become quite worn over time, was no longer effective and had to be replaced (moisture showed up as peeling paint on the garage ceiling). So, I shoveled off the roofing gravel, removed the surrounding fascia sheet metal and the old bitumen waterproofing. A friend who is a carpenter helped me with this and provided materials both for the new waterproofing (Resitrix SW W FullBond) and a new fascia sheet. The waterproofing was applied according to the manufacturer’s instructions, but without installing any insulation beforehand. At the time, my thinking was: “Why insulate a detached garage?” — a thought that might turn out to be costly in hindsight... My carpenter friend also advised that insulation was not necessary.
The flat roof overhangs on one side beyond the garage itself. The drain, which was originally routed through the fascia, was relocated to this overhang area (covering the passage between the house and garage).
Now to the main problem: During the transition seasons and in winter (currently), water (probably condensation or sweating) is coming out from the gap between the core hole and the drain pipe. I cannot completely rule out a leak in the new waterproofing, but I have checked the welded seams multiple times. Moreover, this issue does not occur during the warmer months. Especially in the colder months, the garage is usually (significantly) cooler than the outside air during the day, which strengthens my suspicion of condensation. Independently of this problem, it is planned to install a green roof on the garage, which may reduce heat loss due to radiation, especially on colder nights. However, I doubt whether this will be sufficient...
Reluctantly, though I acknowledge the mistake of not installing insulation, I would prefer not to tear down the existing materials just to install insulation afterwards. Do you have any tips or suggestions on how to possibly counter this problem?
A somewhat desperate consultation with an AI brought up the following suggestions:
- Closed-cell insulation around the drain, for example using Armaflex,
- Insulating the underside of the roof overhang,
- Insulating the interior side of the garage ceiling (which I would rather avoid).
What do you think about these options?
I am grateful for any idea or advice that could help me address this issue. I will respond as quickly as possible to any questions or requests for further details.
I am facing the following issue:
Two years ago, I started renovating our detached flat-roof garage (concrete ceiling, masonry walls). The concrete ceiling extends on one side beyond the garage wall to cover the passage between the garage and the house.
The main problem was that the old waterproofing, which had become quite worn over time, was no longer effective and had to be replaced (moisture showed up as peeling paint on the garage ceiling). So, I shoveled off the roofing gravel, removed the surrounding fascia sheet metal and the old bitumen waterproofing. A friend who is a carpenter helped me with this and provided materials both for the new waterproofing (Resitrix SW W FullBond) and a new fascia sheet. The waterproofing was applied according to the manufacturer’s instructions, but without installing any insulation beforehand. At the time, my thinking was: “Why insulate a detached garage?” — a thought that might turn out to be costly in hindsight... My carpenter friend also advised that insulation was not necessary.
The flat roof overhangs on one side beyond the garage itself. The drain, which was originally routed through the fascia, was relocated to this overhang area (covering the passage between the house and garage).
Now to the main problem: During the transition seasons and in winter (currently), water (probably condensation or sweating) is coming out from the gap between the core hole and the drain pipe. I cannot completely rule out a leak in the new waterproofing, but I have checked the welded seams multiple times. Moreover, this issue does not occur during the warmer months. Especially in the colder months, the garage is usually (significantly) cooler than the outside air during the day, which strengthens my suspicion of condensation. Independently of this problem, it is planned to install a green roof on the garage, which may reduce heat loss due to radiation, especially on colder nights. However, I doubt whether this will be sufficient...
Reluctantly, though I acknowledge the mistake of not installing insulation, I would prefer not to tear down the existing materials just to install insulation afterwards. Do you have any tips or suggestions on how to possibly counter this problem?
A somewhat desperate consultation with an AI brought up the following suggestions:
- Closed-cell insulation around the drain, for example using Armaflex,
- Insulating the underside of the roof overhang,
- Insulating the interior side of the garage ceiling (which I would rather avoid).
What do you think about these options?
I am grateful for any idea or advice that could help me address this issue. I will respond as quickly as possible to any questions or requests for further details.
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