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00:06:420Michele De Carli: turned them into the, technologies, okay? So, we have seen, so far, okay, the…
00:15:570Michele De Carli: the load, okay, calculation, so we have seen how to calculate the peak loads, okay, how to size to design the system, okay? And now we enter into the technological,
00:30:30Michele De Carli: aspects, okay?
00:31:990Michele De Carli: Again, as I told you, we… just to summarize, we could have different types of heat lane cooling solution, okay, so…
00:43:200Michele De Carli: just water, okay, water in there, and, and, full air systems, okay?
00:51:660Michele De Carli: I told you, I prefer to start looking before at the ventilation system, okay? So, a full air system, ventilation system, so
01:01:410Michele De Carli: to look at everything which is related to the air movement in the building, okay, then we will switch to the hydronic systems, so to the water solutions, okay? And,
01:14:480Michele De Carli: What we are going to see in the… in the…
01:17:920Michele De Carli: in, energy. And then we go into designations, okay? But I say,
01:24:830Michele De Carli: We start from this letter here, the new section, okay, on the ventilation system, and how to distribute the air to the side of the building, and also how to, let's say, provide this air.
01:40:510Michele De Carli: We are going to see, as they say, next step, the full air system, okay, which we both somehow question us yesterday, okay?
01:51:990Michele De Carli: But before doing that, I would like to, start with the, the…
02:01:610Michele De Carli: simplest solution for ventilation, okay? So, the simplest solution for ventilation means, prefabricated solutions, as we will see, okay? So, here we don't have to do many
02:15:710Michele De Carli: sizing calculations, okay, not, no, no, no particular calculations, okay, just a few calculations.
02:25:590Michele De Carli: But it is important because we start looking at the components, okay, and we start understanding the mitigation, and we are also introducing, or we are resuming, okay, part of the
02:38:420Michele De Carli: importance of the mitigation principles that we have seen in the beginning of the course, when we talked about in the back.
02:46:220Michele De Carli: Okay, so we start with the more… the simple solution, which is the so-called controlled mechanical ventilation, okay? CMV in English, UMHC, okay, UMHE, DCM in…
03:04:140Michele De Carli: Let's see.
03:06:770Michele De Carli: Vers, okay, in Italian, okay? And it's mainly for residential buildings, or for small, okay, service buildings, okay, where we need to provide, not so much more, okay?
03:22:730Michele De Carli: Okay, so…
03:27:680Michele De Carli: If that's what you want to see.
03:35:130Michele De Carli: I'm sure.
03:36:210Michele De Carli: Oh, yes, okay.
03:37:270Michele De Carli: Okay, so now… Let's, so it's… I will go very quick, because part of this,
03:45:470Michele De Carli: information we have already, okay? As I told you, in the… when we talked about in the air quality, okay, in residential buildings, in the past, we had, leakages in the, in the structure, so we had also different,
04:03:960Michele De Carli: behavior, okay, so windows were more open, okay, in the past than we are today.
04:09:800Michele De Carli: today, people, they just spend their life in the house only at nighttime, okay? And, as I told you, you're not, you're not, able to control the ventilation, parade, violence, or poverty, okay?
04:29:930Michele De Carli: So, we have also greater tightness, okay, of the windows, okay, so we have lower leakages in the handle, and we are not able, okay, to fulfill the air.
04:48:340Michele De Carli: The air, change rates by just the Opening and closing the leak.
04:54:690Michele De Carli: Here you can see, I told you, okay, this is the study that we have seen, I told you, but this is the study I told you in Sweden, where with half or 0.6 air changes per hour, you can see that the risk, okay, this is based on
05:13:810Michele De Carli: thousands of buildings, okay, of dwellings, okay? We are not talking about 2 or 3 dwellings, we are talking about
05:20:760Michele De Carli: Thousands, okay, of dwellings, which were investigated, and they made a very, very good work, and they found that the risk of asthma, okay, relative risk of,
05:35:160Michele De Carli: allergy symptoms was limited when we had at least 0.5 changes. Okay, 0.6 better?
05:45:950Michele De Carli: So that means that half air change rate, which was, let's say, historically used, okay, is a good way. If we have less than 0.5, so 0.2, 0.3, we have
06:02:500Michele De Carli: an increase of the allergic symptoms, and of course, we could have some problems in the, as you can see here, mold doors, okay, which is usually named, service condensation problem, okay? The ones who made the emergency business model.
06:18:750Michele De Carli: What is this problem? The problem is that, you have this mold growth when, locally, okay, you are in, the range of, between 80 and 100% environmental humidity, okay? So if, if,
06:37:60Michele De Carli: Based on the humidity content that you have inside of the room, and the temperature that you might have in the coldest part of the envelope, okay?
06:48:370Michele De Carli: If, in, locally, the, the, the, the minimum temperature in the wall could reach this, this area here, then you have condensation for it.
07:01:980Michele De Carli: Again, we are seeing, based on the vapor… the vapor balance, that in order to keep the
07:08:820Michele De Carli: The… then… then… the house,
07:15:890Michele De Carli: dry, we just need to ventilate. In wintertime, when we have ventilation, if we have enough ventilation, we could reduce the relative humidity, the…
07:28:140Michele De Carli: The humidity ratio inside of the room, and if we… if we lower this… the humidity ratio, okay, then the minimum temperature, okay, of the potential
07:39:910Michele De Carli: Little girls.
07:41:260Michele De Carli: Will, okay, lead to very long temperatures, and you cannot reach these temperatures in that
07:47:500Michele De Carli: Okay? So, the mechanical ventilation, okay, is something that we need, because it's the only way we could keep the… we could keep the relative humidity low in the peak, okay?
08:03:140Michele De Carli: And what is important to understand is that ventilation is
08:09:210Michele De Carli: needed. If we need… if we had to spend energy on the ventilation, we had to spend energy in the ventilation as much as the energy that we…
08:19:580Michele De Carli: Spend for the domestic hot water, okay?
08:22:640Michele De Carli: Or other, okay, or also for heating it. Okay, so it is not, it is not… and of course, we could save some energy by, of course, the heat recovery, okay? Okay, so…
08:38:740Michele De Carli: before going into the details, okay, I just want to summarize the typical, possibilities that we have, okay? Apart the ironization of airing, okay, which is the first solution, which is
08:52:890Michele De Carli: I mean, it has to be neglected, especially in new buildings, okay?
08:58:970Michele De Carli: We'll see how, okay? We might have natural ventilation, okay, but in this case, we needed to have, to design the openings on the walls, okay?
09:11:610Michele De Carli: So the natural evolution has… needs, anyway, a design, okay, so… And usually, it is…
09:21:130Michele De Carli: No, right, it's not… it's not complicated, but we need to make some specific operation, okay?
09:28:360Michele De Carli: Mechanical ventilation is what you could use as a…
09:34:480Michele De Carli: own condition, and you will see that we have some prefabricated solutions, okay?
09:39:980Michele De Carli: Or we could use a mix of two, okay, which is…
09:44:280Michele De Carli: not really easy, but you can do that, okay? So you could use the so-called hybrid ventilation, which could be a mix of natural and mechanical ventilation. In this case, the openings that you have on the walls, okay, in the BV, should be closed in order to add the mechanical ventilation.
10:03:40Michele De Carli: Dave?
10:05:520Michele De Carli: Okay, so, aeration is, Something that you need to…
10:11:980Michele De Carli: to adoint, okay, so here you have some, some, some, some definitions, okay? And, I want to argue that infiltration could occur in different, okay, parts of the buildings, okay, could occur in the windows, okay, or when the windows is attached to the…
10:31:240Michele De Carli: the building, okay. Also, okay, so part of regulation, okay, food would be… would come from here, okay, from the, tables, not the tables, but the, the, the, the…
10:45:670Michele De Carli: the plastic, ducts, okay, the correlating backs, right? And the holes that are used for, hosting the cables, or the connecting dots there, you might have infiltration or something directly.
11:00:00Michele De Carli: Okay, so…
11:02:570Michele De Carli: And natural ventilation, as I told you, is something that you have to consider, but you need to, to, let's say, consider, okay, openings, to size the openings, and, of course, with natural ventilation, as we experienced, okay, some days ago, you have noise, okay, you are not allowed to…
11:23:350Michele De Carli: So if there is a noisy space outside, you have noisy space social intercept, okay.
11:29:360Michele De Carli: And, of course.
11:31:430Michele De Carli: One important issue is that the natural ventilation, is a variable ventilation, okay? So it depends on the local conditions outside, okay? Especially windy or not conditions, okay? So that is something that you have to consider.
11:49:700Michele De Carli: All right, so tomorrow, we're going to see the ventilation system for residential buildings, okay? And, we start from this side, okay?
12:02:320Michele De Carli: seems okay, it is.
12:10:340Michele De Carli: I stopped there.
12:11:950Michele De Carli: Recording?
12:14:970Michele De Carli: Is that okay?