You'd really have to cut into a wall to know what to look for in the construction of the building. Everyone has their theories whether new buildings are better because they are new construction or older buildings because they are sturdier... or new buildings are worse because they are a quick construction where corners are cut or old buildings because they are run down Each of those statements has truth to it, but you also new buildings have strict codes that they must adhere to. Inspectors are required to visit construction sites at intervals and sign off stating that the building has met all of the codes (they can also require the general contractors to undo their work just to prove that it is up to code) Anything can really cause sound to travel in a building whether it be hard surfaces like wood, steel, or concrete. It depends on if there is a path for the sound to travel through space or each of those building materials (depending on how they are or are not touching each other). There have to be fire rated walls between rowhouses and apartments. These are usually thicker walls. They also have to meet insulation requirements (governed by local codes) this helps eliminate noises now too. There are soundproofing barriers incorporated into insulation that are 'newer' to the industry, but for these it depends on if the owner wants it or the architect wants to specify to use it. Now older buildings are typically 'granfathered' into the new codes, meaning that they do not have to comply with them until there is a major renovation done. This doesnt mean to shy away from them, you just really have to do your homework. Enough mumbo-jumbo... When looking for a new place I would start by looking for a place on a first floor or top floor as well as one that has as many outside walls as possible, this helps reduce the noisy neighbors you might have to deal with. (When I moved into my townhouse I got a map and a list of the available townhouses to rent. I checked them all out before I chose the one i did.) I would also look for a brick or concrete cladded building. I would shy away from any building that has wood or vynl siding. You will hear the wind much easier if it is sided. Also, you'll hear the thermal movement. So if the sun heats up the vynl and it expands or the cold shrinks it, you might hear the pieces moving against each other. When you visit the place, go multiple times varying throughout the day if you can. You never know which neighbors are going to be home when. Walk around the complex. Talk to the neighbors, get their opinions. They would know better than management. Go on the web and google apartment ratings. There are plenty of sites where tenants can post their comments about their experiences there. (Keep in mind someone will tell 1-2 people if they have a good experience and 20-25 people if they have a bad experience so dont be surprised if you find quite a few negative comments posted, just use it as a guide) Tap on the walls, if they sound hollow you might have noise issues, if they sound solid, its a good bet that will help eliminate sounds. Capeting will be key! When you move in, put lots of rugs down even on top of carpeting. Make sure you put heavy drapes up. Fill your rooms with furniture, dont keep very empty rooms. Add plants! The point is the more soft surfaces that you have, the harder it is for sounds to continue to travel. Ok, sorry for the ramble, hope it helps. Good luck with the apartment hunt!

Adaptive reuse and infill housing are code words for the rehabilitation of exiting urban buildings where the former use is no longer viable or the buildings are damaged and abandoned. You are looking at an urban land use program which I doubt applies to your project unless you have bought an abandoned building. You should be looking at the City of Ashville Zoning ordinance as linked below. Sec. 7-5-4. "Uses by right, subject to special requirements" says in an RS8 district you can built a single-family dwelling on a min. 5,000 s.f. lot with a min, 50 ft lot width, a min. front setback of 15 ft, a min. side setbacks of 6 ft, a min. rear setback 15 ft, and a max. height of 40 ft. There are other requirements regarding open space and landscaping as well. The dwelling can have one accessory apartment with a max. gross floor area of 500 s.f. or 25% of the area of the principal single-family dwelling, which ever is greater. But the apartment area cannot be greater than 50% of the principal single-family dwelling area. It appears a duplex is allowed but it s a Conditional use requiring an unusual amount of review by the Planning and Zoning Commission as well as public hearings and approval of the City Council. You are treating this issue as if it were uncomplicated and not worthy of expert assistance at this point in the project. I do this for a living and I assure you that your approach is a serious mistake. If you want to go this route hire a zoning lawyer or an architect and avoid the inevitable red herrings and wild goose chases. I make no representation of the accuracy of the above information; that costs extra. Here is a link that might be useful: Ashville Zoning Ordinance

I have friends who have a loft area between their upstairs bedrooms and I always thought it was so nice. So when I started looking for a new house, I mentioned to them that I liked their floorplan and they said the loft is just wasted space. They never use it. If they have the tv on, the sound travels through the house. And there's no door, so it always has to be tidy if guests come over, especially if they're staying for the weekend or something. They wish there was a door to close it off if it's a mess or to allow people to do separate things upstairs and downstairs without the noise traveling. In regards to children, I currently have 2 under 2 and I work full time..... so in the evenings, when we get home and need to make dinner, I would never send the kids upstairs to play while I make dinner. I need a playroom or space for toys on the first floor near the kitchen. So as a playroom, a loft or bonus room upstairs might work on weekends (or if you are a stay-at-home mom/dad) or in the future when the kids are older, but it won't be fully utilized while the kids are little. Just food for thought..... Depending on your first floor layout and your families needs, maybe you could put an office in the loft/bonus room and utilize a downstairs office as a playroom while kids are little.

Assuming you have adequate wall thickness to accommodate the larger outside diameter, replacing the vertical section of plastic pipe with the equivalent diameter cast iron pipe should make the noise less objectionable. We did this as standard practice on all our homes for over 30 years. Last year our plumber informed me that he made service calls to three homes in our local area and found longitudinal stress cracks in cast iron pipes that were 25 +/- years old. The cast iron pipes were made in the U.S.A. by a quality manufacturer so we can't blame the problem on some cheap import. We've since discontinued the use of cast iron in favor of insulation. We do have water quality issues in our area which may contribute to the problem. In any case, we believe that eliminating a potential failure in a non-moving part of a home which has a life expectancy of much more than 25 years is a good thing.