I am renovating a room in a brick house from 1965. I have removed the tretex from the walls and ceiling to replace it with drywall. Behind the tretex is tongue and groove wood. The exterior walls and ceiling differ slightly because there is a type of paper nailed to the tongue and groove. It is black and smells a bit like tar. If I were to replace it with a more modern odorless variant, what should I choose? Age-resistant plastic?
In another room, I didn't replace the paper, just screwed the drywall onto it. The tar smell disappeared as soon as the drywall was on, so it's not really a problem... but I thought maybe it might be worth replacing while I have the opportunity.
In another room, I didn't replace the paper, just screwed the drywall onto it. The tar smell disappeared as soon as the drywall was on, so it's not really a problem... but I thought maybe it might be worth replacing while I have the opportunity.
It is regular windproof membrane that is there. If you are not going to install new ventilation in the house (like FTX), you should replace the windproof membrane where it may be damaged and otherwise leave it as is. If you change the ventilation system in the house, you can use age-resistant plastic.
Thank you for the quick response! It was precisely the tar smell that made me think it might be some type of moisture barrier paper. But I guess plastic seals even more so one should probably be careful about replacing it as you say (unless you change the ventilation).. Hmm, when I think about it, that was probably my reasoning when I fixed the other room. 
You should probably be careful about switching to completely impermeable materials in an old house that is designed to allow moisture to escape.
You are right, I may not express myself well. But in an old house, my opinion is that one should be careful about replacing breathable materials that allow some moisture movement with completely sealed materials that don't let anything through. In older houses that don't have as efficient ventilation as newer ones, a little moisture will always travel in the wall, and it's good if the materials can breathe. Additionally, if you have an older house that doesn't have planned air supply with air vents and the like, you can easily get strange odors in the house when the air has to be taken from somewhere else than where it previously came in, and now you have installed a completely sealed plastic.
If a building construction is completely open, moisture, i.e., water in solution in the air, will, through diffusion (equalization), migrate out through the wall construction. Diffusion is driven by concentration. Sooner or later, especially during the heating season, there is a risk of reaching the dew point inside the building construction, due to the temperature gradient within it. This leads to precipitation of water (precipitation=same word, and same phenomenon as precipitation in English). To prevent this, a layer as impermeable as possible is installed on the warm side of the construction. One uses what is available and reasonably priced. Previously, this material was often tar paper like Vestapapp or similar, but sometimes also slightly thicker tar paper. The latter has relatively good vapor resistance (low permeability to steam). For those particularly interested, permeability is the product of diffusivity and solubility. Nowadays, the material with the best price/performance is age-resistant plastic. It is the technically best solution for the house.
If plastic is installed in an old house, one will wake up in the morning to find the air in the room extremely poor. The building construction has been protected, but the bad air, which would otherwise have been absorbed by the house, is something you have to breathe. Therefore, one should review their ventilation. You need both an inflow and an outflow in a room, and both should be reviewed. An open window is an uneconomical and rather poor solution to the problem.
I do not want to be smug and condescending in any way, but what you often hear about houses that "breathe," wood that "lives," etc., is invented by people who have no knowledge of physical processes. It is unfortunate. Pseudoscience is best suited for religious communities and healing circles and the like. When pseudoscience is applied to real physical, chemical, and biological systems, there is a risk that people or property will be harmed.
If plastic is installed in an old house, one will wake up in the morning to find the air in the room extremely poor. The building construction has been protected, but the bad air, which would otherwise have been absorbed by the house, is something you have to breathe. Therefore, one should review their ventilation. You need both an inflow and an outflow in a room, and both should be reviewed. An open window is an uneconomical and rather poor solution to the problem.
I do not want to be smug and condescending in any way, but what you often hear about houses that "breathe," wood that "lives," etc., is invented by people who have no knowledge of physical processes. It is unfortunate. Pseudoscience is best suited for religious communities and healing circles and the like. When pseudoscience is applied to real physical, chemical, and biological systems, there is a risk that people or property will be harmed.