Home Improvement--General/Stove exhaust fan venting
QUESTION: I am in process of adding a basement suite to my son's home. It's time to put in the stove exhaust fan venting. The total length from above stove to outside is 22 feet, and its path is from unit up to space between floor joists (upstairs),covered with drywall,through the new kitchen, then through a bedroom to the outside wall. Above the vent pipe is my son's master bedroom upstairs. My questions are: 1) is it necessary to insulate the 6" metal venting re moisture? 2) if not, could I use Roxul Safe'n'Sound insulation for sound control due to my son's bedroom being right above the pipe? 3) if moisture control necessary, what insulation should I use? 4) Or...none? 5) Is 22 feet too long for the pipe? The exhaust fan is a medium quality (1.5 sones), medium price exhaust fan unit. I have nowhere else to install it without cutting through a door header and a floor joist and this way it's at least a completely straight run. I really appreciate your advice.I hope my questions make sense.
ANSWER: I would install a good quality ventless range hood that has a filter made of charcoal. Charcoal filters are excellent and are used from fish tank filter to medical device filters. A goodquality ductless fan is just a effective as a vented range hood fan. It must have a rating of at least an airflow rating of 200 cfm. An excellent ventless fan for the price, that I have installed in many homes, is the Whirlpool Model Model # UXT5230BDS. It has an airflow rating of almost double the minimim requirements. Home Depot has it on sale for $199 this week. regular price is $279. An effective ventless range hood usually start just over a hundred dollars and go as high as $600 for professional models. Stay away from the low price bargin fans.
If you still want to install a vented fan, I will answer those questions in detail. But if you want to save time and labor, I would go with a good quality ventless unit.
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QUESTION: Thanks for your very quick response. I'm in Canada so the Home Depot price is higher on this fan, and not on sale. However, I have already purchased a comparable one that apparently can be recirculating as well (which I can't return as bought too long ago - multiple delays on this project). Advice I was given previously said I should duct out the moisture etc due to it being in a basement suite and not wanting to keep it in the building and going to the upstairs. So, if possible, I would appreciate if you could answer my initial questions. Thank you so much.
ANSWER: There is a formula that is used by HVAC installers that should be followed to ensure any type of external vented fans to work properly. So I would need more information to give you the correct answer. Kitchen cubic feet, the amount of air in your kitchen space and the CFM rating of your exhaust fan. This will determine the size of the vent pipe (six inch duct work should be more than enough in your case) and if there is a need for replacement air flow into the kitchen to make sure the fan is exhausting cooking fumes properly to the outside.
I would need the length, wide and ceiling height of the kitchen to answer your question correctly. Also is the kitchen in an open floor plan or separated by walls from the other living space. I am assuming you are installing a regular 30 inch stove/range.
To give you quick answers to your questions...22ft fun of six vent pipe will work as long as the proper air flow is achieved, which means replacing the air that is being moved out of the room with air coming into the room. if there are no spots the vent pipe will be exposed to cold weather, the only insulation you would need is sound deafening insulation. The insulation you mention is fine. The only problem I see if cutting out parts of the joists to run the pipe through. I do not recommend doing that if it is near a bearing wall of the floor joist is say 12 ft in length. Door headers are required by most building codes on non bearing walls, so cutting through those should be ok if it is not a door in a load bearing wall.
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QUESTION: The kitchen is approx 850 cf (8'widex13'longx92"high). I don't have to cut into any joists as they run the right direction from the 30" stove/fan placement to fit the 6" pipe all the way to the outside wall (through bedroom which is next to kitchen). I would have to cut through a joist to put it through the door header which is why I wanted to go the distance through the bedroom ceiling to outside. The 36" entrance door that opens to fresh outside air is between living room and kitchen areas (open concept)so replacement air occurs every time door is opened, I would think. Living room area is 3' wider than kitchen area (11x14). The range hood is 220 cfm minimum (it's at my son's so can't check for sure now). So it sounds like this will work for us. Once I figure out how to get the soundproofing insulation into the channel without cutting out too much of the existing ceiling drywall (all of which is being covered with 2nd layer of 5/8" Fireguard drywall). If this sounds okay to you,thank you very much for your time and expertise.
I have another question: I have also put together a music studio in the basement, next to the suite kitchen. Entrance to it is at bottom of stairs from my son's living space upstairs. At bottom of stairs straight ahead is the door to suite kitchen, to left is door to (large) laundry room, to right is door to music studio. Because of the flooring requirements in studio for sound control, it appears that the entrance door to studio will have to open out into foyer. Are there door hinges that are "lockable" so no one besides my son could gain access to the studio and expensive equipment by taking the door off the hinges? If not,is it possible to trim the height of the door (solid wood)to accommodate the floor height?
You can buy door hinges that have a locking hinge pins. They can be removed only when the door is open. The screws are one way screws that can be tightened only. This will stop most thieves from being able to open the door. But some thieves carry 18 volt cordless drills with them. If someone were to buy the special bit to remove one way screws, then they can just unscrew the hinge off the door. An optional solution to that is to replace the screws with threaded round headed carriage bolts. Drill the proper size hole all the way through the door. On the inside, use a washer and nut. Measure the thickness of the door and buy the bolts an inch longer. Do the same where the hinges screw into the wall. The washer & nut on the inside of the door will make it almost impossible to remove the hinges. Also and the door handle part. Replace the screws for the striker plate that came with the door handle set with three inch drywall screws. A three inch screw is long enough to go into the 2"x4" studs behind the door frame making it a lot harder if someone tried using a pry bar to open the door.
Yes a solid wood door can be trimmed. To ensure you get a straight cut, I take a straight piece of 1"x4" wood, clamp it down to the door, and this creates a guide the edge of the circular saw can follow to get a straight cut. Before I clamp the 1"x4" to the door, I use it as a guide to score the pencil line showing how much of the door I am cutting with a utility knife. This will prevent the saw blade from possibly making small jagged edges on one side of the door.
I will answer the the fan question later this evening.
Insulate the exhaust duct pipe anywhere that it runs through an unheated area. I would use the sound insulation where the pipe runs through the bedroom wall. As long as the exhaust duct runs mostly straight up, with a few 45 degree bends, then a 220CF should be fine. Try to avoid
any 90 degree bends or turns in the exhaust duct work. I will answer the the fan question later this evening.