Introduction / Preface
Hello!
My name is Christian, and I am 27 years old. This year, I completed my bachelor’s degree in Energy and Environmental Engineering and am now pursuing a master’s in Renewable Energies. I am an enthusiastic DIYer, if you can still call it that with my own lathe, milling machine, welding equipment, and so on.
Recently, I became the "owner" of a single-family house and am currently renovating it. Being a self-proclaimed "tech geek," I want to equip the house with some nice gadgets. I’m doing the renovation myself, and so far, the work is progressing well. As part of the refurbishment, a central ventilation system with heat recovery is planned to be installed (or at least the ductwork pre-installed).
The planned system
The house has approximately 140m² (1507 ft²) of living space plus a full basement. My plan is to install a central system in the heating basement. This system will be completely self-built as a low-budget solution.
The ductwork
Supply air will be delivered to the bedroom and living room (which is combined with the dining area and open kitchen).
Exhaust air will be extracted from the shower bathroom in the basement and the bathroom with a bathtub upstairs.
Since I am still at the "shell construction" phase, I want to lay all necessary ducts now. Due to structural reasons, I plan to use DN70 HT pipes (drainage pipes) for both supply and exhaust ducts.
QUESTIONS
1. Is there any reason not to use HT pipes (wastewater pipes) for the air ducts?
2. The internal diameter of the pipes is 70mm (2.75 inches). At an air velocity of 2 m/s (6.6 ft/s) in the main duct, I achieve about 28 m³/h (16.5 cfm), which means approximately 14 m³/h (8.2 cfm) each for the living room and the bedroom. Will an air velocity of 2 m/s already cause noticeable airflow noise?
3. The system is intended to provide “supportive” ventilation. Do you think it’s feasible to achieve effective ventilation support with the 70mm diameter ducts?
4. The air must of course flow from the “supply air rooms” to the “exhaust air rooms.” In the living room, I plan to install a ventilation grille in the door for this purpose. However, I want to avoid this in the bedroom for noise reasons and to prevent shortcut airflow. I have heard about sound-insulated wall connectors but don’t really know where to get them. Does anyone have tips?
5. Does anyone with experience in this area feel like visiting my construction site (in 21217 Seevetal near Hamburg) to offer helpful advice? I’m diving into this project completely on my own and would really appreciate the chance to exchange experiences.
Many thanks in advance!!
Hello!
My name is Christian, and I am 27 years old. This year, I completed my bachelor’s degree in Energy and Environmental Engineering and am now pursuing a master’s in Renewable Energies. I am an enthusiastic DIYer, if you can still call it that with my own lathe, milling machine, welding equipment, and so on.
Recently, I became the "owner" of a single-family house and am currently renovating it. Being a self-proclaimed "tech geek," I want to equip the house with some nice gadgets. I’m doing the renovation myself, and so far, the work is progressing well. As part of the refurbishment, a central ventilation system with heat recovery is planned to be installed (or at least the ductwork pre-installed).
The planned system
The house has approximately 140m² (1507 ft²) of living space plus a full basement. My plan is to install a central system in the heating basement. This system will be completely self-built as a low-budget solution.
The ductwork
Supply air will be delivered to the bedroom and living room (which is combined with the dining area and open kitchen).
Exhaust air will be extracted from the shower bathroom in the basement and the bathroom with a bathtub upstairs.
Since I am still at the "shell construction" phase, I want to lay all necessary ducts now. Due to structural reasons, I plan to use DN70 HT pipes (drainage pipes) for both supply and exhaust ducts.
QUESTIONS
1. Is there any reason not to use HT pipes (wastewater pipes) for the air ducts?
2. The internal diameter of the pipes is 70mm (2.75 inches). At an air velocity of 2 m/s (6.6 ft/s) in the main duct, I achieve about 28 m³/h (16.5 cfm), which means approximately 14 m³/h (8.2 cfm) each for the living room and the bedroom. Will an air velocity of 2 m/s already cause noticeable airflow noise?
3. The system is intended to provide “supportive” ventilation. Do you think it’s feasible to achieve effective ventilation support with the 70mm diameter ducts?
4. The air must of course flow from the “supply air rooms” to the “exhaust air rooms.” In the living room, I plan to install a ventilation grille in the door for this purpose. However, I want to avoid this in the bedroom for noise reasons and to prevent shortcut airflow. I have heard about sound-insulated wall connectors but don’t really know where to get them. Does anyone have tips?
5. Does anyone with experience in this area feel like visiting my construction site (in 21217 Seevetal near Hamburg) to offer helpful advice? I’m diving into this project completely on my own and would really appreciate the chance to exchange experiences.
Many thanks in advance!!
S
Sebastian7918 Feb 2015 11:01Uh, no... telephone noise spreads through the wiring – you didn’t consider that. The other issue normally has no impact on sound transmission through the ventilation system.
You can feel the airflow if you stand right in front of the door – but who does that? It’s certainly not a storm...
You can feel the airflow if you stand right in front of the door – but who does that? It’s certainly not a storm...
The airflow rates depend on the size of the house and how quickly you want the air to be exchanged...
180 is already quite low for a "typical" single-family home... you can imagine that the system would basically be running at full capacity continuously, which unnecessarily consumes electricity. That’s why such systems usually have some reserve capacity and operate more often at partial load, for example.
As mentioned before, the ventilation ducts are smooth on the inside... they are only corrugated on the outside for kink protection, etc.
Why not simply run the intake duct through the wall? The shorter, the better...
180 is already quite low for a "typical" single-family home... you can imagine that the system would basically be running at full capacity continuously, which unnecessarily consumes electricity. That’s why such systems usually have some reserve capacity and operate more often at partial load, for example.
As mentioned before, the ventilation ducts are smooth on the inside... they are only corrugated on the outside for kink protection, etc.
Why not simply run the intake duct through the wall? The shorter, the better...
Z
Zip-Freak18 Feb 2015 15:50Okay... so it’s better to slightly increase the door gap rather than install shafts in the walls?
Now I understand what is meant by telephone noise! Yes, I don’t think that will be a problem. I planned to install a silencer in front of the air supply in the bedroom (vent connection in the ceiling)... for the other pipes, it’s not a big issue if some noise is transmitted.
Now I understand what is meant by telephone noise! Yes, I don’t think that will be a problem. I planned to install a silencer in front of the air supply in the bedroom (vent connection in the ceiling)... for the other pipes, it’s not a big issue if some noise is transmitted.
S
Sebastian791 Mar 2015 09:58Which plastic pipes?