6 reasons for condensation on the front door and methods for eliminating it
Only residents of apartment buildings and people who were lucky with the quality of the installation, the design of the door leaf itself, and at the same time the design of the house have never encountered such a problem as condensation on the front door. What did you think: there are quite a lot of factors that need to be taken into account to eliminate the problem, so in search of the source of condensation, you will have to inspect and analyze the structure on several fronts.
Why does the canvas fog up and why is it dangerous?
Condensation on the entrance metal door, and not only that, forms due to the difference in surface and air temperatures. The same phenomenon can be observed on an aluminum can from a refrigerator or on car windows during the cold season. When the air in a room is relatively warm and the surface is colder, at certain readings of air temperature and humidity it reaches the dew point temperature, when the vapor from the air turns into the form of a liquid and collects on this very surface.
For example, at a temperature in the dressing room of 21˚C and a humidity of 50%, the dew point for the door surface will be 10.2 degrees. Considering the high thermal and, in our case, cold conductivity of the metal, at low temperatures outside, the door in a private house will be consistently covered with condensation.
Dew or even frost on the inside of the front door does not add comfort to the environment, but the most unpleasant thing is that iron doors fog up not only from the outside, but also from the inside, which can lead to rapid failure of the structure. When buying an entrance door, everyone wants to get high quality at a reasonable price, but if you decide to save money and buy a system without internal anti-corrosion treatment for a country house, be prepared for the fact that it will not last long. Unless, of course, you solve the fogging problem before the canvas rusts.
Advice
The main thing is to understand why the door sweats and to identify the weak side of the frame, door leaf or room adjacent to it.
How to determine the cause of fogging and what to do?
By and large, there is only one reason - the aforementioned temperature difference. But it can arise due to several factors.
- The canvas is poorly insulated
Mainly, entrance doors sweat due to poor insulation. If you bought a canvas without high-quality insulation, ways to correct the situation are to try to insulate it yourself or change the canvas. The cavities in the door leaf can be filled with polyurethane foam, but it is still better to think about a high-quality insulation layer inside the door before purchasing.
- The box is poorly insulated
In this case, condensation can form not only on the box itself, but also on the canvas around the perimeter of contact with it. You can insulate it using the same foam, mineral wool or polystyrene foam, and since you still have to dismantle the box for this, check whether the doorway is foamed well enough. If there were cavities between it and the box, the cause of fogging could lie in them, and it is not the manufacturers who should be blamed, but the installers.
Advice
In addition to insulating the frame and canvas, you can also insulate the slopes from the outside, if the external finishing of the facades allows it.
- Violation of tightness
The door may become covered with condensation if the seal between the door leaf and the frame is broken, which can be quite easily checked by the presence of drafts. In this case, dew will accumulate mainly around the perimeter of the canvas and the box. In this case, a regular self-adhesive rubber seal, which must be attached to the box and the canvas around the perimeter, will help solve the problem.
Important!
If a metal door is cheap and trimmed with decorative panels, it is not a fact that the manufacturers have properly treated the metal underneath with anti-corrosion treatment. If the panels are poorly attached and there are voids between them and the metal, then the door will begin to sweat under the panels, and you will only find out about it when it fails.
- Bridges of cold
Another reason why the front door sweats even with good insulation is the cold bridges that exist in almost all doors. Cold bridges are through metal elements, such as a lock or stiffening ribs, that are not separated by thermal insulation or at least voids and perfectly conduct cold to the inner surface of the canvas. Even when foaming the cavities in the canvas, local sweating in the area of such a bridge can only be avoided using the following method.
Advice
Sometimes cold bridges simply cannot be avoided: usually it’s a lock and a peephole, and that’s enough. But in the case of a lock, you can at least use a retractable escutcheon or not choose models with vertical bolts.
- The room is too cold
Sometimes the front door leads directly to the corridor, but most often the house has a vestibule.An unheated vestibule in which the air is warmer than outside, the cold from which lowers the temperature of the internal surface due to the above reasons. What to do if the metal entrance door sweats in this case? Try to slightly equalize the temperature of the inner surface of the canvas and the air in the vestibule using heating. The smaller the gap between these indicators, the greater the humidity required for dew to occur. If you heat the air to 24 degrees, then with an average humidity of 50-60%, you only need to heat the inner surface to 14-16 degrees, which is easy to achieve due to thermal insulation, tightness and, most importantly, warm air. But if it is 15 degrees in the dressing room, then with the same humidity, dew on the entrance doors will fall at 4-7 degrees, and the temperature of the metal sheet without heating in cold weather will be much lower.
Advice
If a vestibule is not provided, insulating the inner surface of the metal door from warmer air using a wooden door will help remove condensation. The wooden door should be installed immediately after the metal one.
- The room is too humid
It’s a shame, but the canvas can fog up even in a heated vestibule: remember, the higher the humidity, the smaller the difference in surface and air temperatures is required for the surface to become wet. For example, at 80% humidity and an air temperature of 24 degrees, dew will fall at a surface temperature of 20.3. That is, very warm and humid is worse than moderately warm and dry.
Of course, fogging doors will not be a problem for you if you buy expensive models with thermal break of cold bridges, heated frames, weather-resistant surface treatment or liquid insulation that insulates the metal from the air.But you won’t have to eliminate this unpleasant phenomenon even with accessible doors if you take care of high-quality insulation and maximum tightness, and also understand a little about the table of humidity and air temperature indicators for the dew point.