26 votes
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What is this tube sticking out of my roof?

Almost certainly a vent for plumbing. It connects to the sewer, so it doesn't need a cap. It's highly likely there's a sink or other fixture nearly below it.
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19 votes

Vent kitchen hood vent to roof turbine vent?

TL;DR: It is explicitly not to code to exhaust into the attic or to use foil pipe It's a bad idea anyway because it puts smoke, grease and warm humid air into your attic which can cause mold growth ...
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  • 28.3k
19 votes
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How does ventilation help in a detached garage

You ask how ventilation helps with reducing humidity. Here's how: An enclosed space, such as a garage, holds the air inside it fairly still. At the same time, it's warmed from the outside by the sun ...
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  • 374
13 votes

Bathroom fan fluctuates in power when using countdown timer switch

There are actually two problems, and they are related: Low Power Fan First I found a customer review on the Lowes web site that said: I gave this only three stars as no where on packaging or ...
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13 votes
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Insulating a wooden shed to provide strong heat rejection

Insulation works both ways, so it'll reduce the heat coming in from the sunlit outer walls as well. Small windows are also favourable in these conditions. For warm but not over the top situations, you ...
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  • 594
10 votes

Vent kitchen hood vent to roof turbine vent?

I don't know where you live, but something to consider is that you're dumping warm, moist air into a potentially cold zone. So some of that air can/will condense in there in winter. Since attics tend ...
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  • 19.8k
10 votes

What is this tube sticking out of my roof?

It's a vent pipe for the plumbing it connects eventually to the sewer. It will catch a small amount of rain but the rain will stay inside the pipe and eventually reach the sewer. You're probably not ...
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  • 13.2k
9 votes
Accepted

Bathroom fan fluctuates in power when using countdown timer switch

Take it back and get a different timer The stock Lutron MA-T51 does not need neutral; however, it accomplishes this by trickling power through the load. This is fine for large loads, but for low ...
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8 votes
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How to fit portable air conditioner hoses through a too small wall vent

You could investigate the rectangular panel that holds the two holes in the wall. Perhaps it can be removed, then you can replace it with a new panel with a suitable hole cut out. You could search ...
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  • 17.1k
8 votes
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Should I install soffit or gable venting with a 3:12 pitch roof?

Code only determines how much ventilation, not what kind. There are different specifications of how much ventilation for the 2 most popular kinds which are considering. With soffit and ridge vents, ...
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  • 31.2k
8 votes

How does ventilation help in a detached garage

Vents at top and bottom (you need both) will help. How much? That varies a bit. But even without any mechanical ventilation, air will flow naturally, particularly as it warms up. However, this is ...
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6 votes
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Bathroom fan with no outside vent

IMO, and IME, bathroom fans should always be vented outside. Bathrooms are one of the biggest (if not the biggest) producer or water vapor in your home. When water vapor is trapped is can cause things ...
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  • 1,958
6 votes

Ventilating a cat box through the dryer exhaust duct

Sharing ducts in that way usually isn't allowed by code for health, comfort, energy efficiency, and fire reasons, among others. It's not a good idea, as you won't balance venting force without a ...
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  • 104k
6 votes
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CFM Required to Ventilate Room to Maintain Temperature

1 BTU is the amount of heat to raise 1 pound of water 1 °F (definition) Specific heat of air is 0.24 (takes 0.24 BTU to raise 1 pound of air 1 °F) A pound of air is about 13.9 cubic feet (at some ...
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  • 133k
5 votes
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Everything in my house vents into the ceiling cavity. Should I change this?

In an apartment building they may have deliberately designed that area to function as a plenum space. That design would -- one hopes -- include selecting/arranging building materials that could ...
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  • 16k
5 votes
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Can we capture the hot, humid air from a gas-powered clothes dryer during winter?

The dryer vent and the combustion vent are one and the same. If you try to use the dryer vent for heating you will have two issues, first excess moisture and second carbon monoxide. Gas dryers get ...
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  • 4,356
5 votes
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Do I need a vent fan in an interior laundry room?

No, this is not a code requirement for laundry rooms in dwelling units (at least in the 2012 IBC). In fact, most dryers are essentially acting as exhaust fans when they run because they take air from ...
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  • 1,042
5 votes
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Will I have trouble running a bathroom fan 10 CFM (25%) stronger than needed?

An extra 10 CFM won't hurt you at all.... If anything, it will get rid of the unwanted moisture faster. I'd wager that article was meant for much larger bathroom fans.
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  • 53.5k
5 votes

Should I install soffit or gable venting with a 3:12 pitch roof?

You want soffit / ridge vents. One of the main purposes of the attic ventilation on asphalt shingle roofs is to allow the roof sheathing to cool such that the shingles are not subjected to ...
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5 votes

CFM Required to Ventilate Room to Maintain Temperature

Excellent answer by Ecnerwal, who besides being one of the top experts on this site, knows more physics than I realized. This question piqued my interest, so I worked through it myself. I get a ...
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  • 1,769
5 votes
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Do I need a new roof to install ridge vents?

Ridge vent requires a channel to be cut down the ridge. With plywood or OSB this usually isn't a problem. With shiplap it may result in very narrow strips being left behind, which could leave the ...
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  • 104k
4 votes
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Can I vent my dryer 'up'?

It really doesn't make any difference when it comes to lint build up. But you might consider putting a secondary lint trap near the dryer to help reduce the amount of lint trapped in the line.
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  • 4,356
4 votes

What's the minimum safe distance from the back of a dryer to a wall?

The minimum recommended distance is one inch: Additional spacing of 1" (25 mm) on all sides of the dryer is recommended to reduce noise transfer. The allowable distance seems to be zero inches.
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  • 12.7k
4 votes

Should I add venting to my solid soffit, and how?

Most roofs have intake and exhaust vents. Soffit vents can be used for intake, but they are not the only means of intake. If you have a vented roof and already have adequate intake venting, you don't ...
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  • 1,669
4 votes
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Tips for building a soundproof room with ventilation

"Insulation" (in the ordinary construction sense) is essentially worthless for blocking sound. But if you need it for the conventional thermal reasons, then certainly go for it. When it comes down to ...
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4 votes
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Reason to Add A Soffit to a Shower

I think you would want the shower ceiling to be the same height as the rest of the bathroom especially with 8 ft ceilings. An average height man with raised arms would touch a 7 ft ceiling. Who wants ...
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  • 19.6k
4 votes

Reason to Add A Soffit to a Shower

No. In fact I removed the one in my previous home after years of dealing with peeling paint. I'm honestly not sure whether it was a fashion trend or whether folks felt like it kept the shower bay ...
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  • 104k
4 votes
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6" Ducting straight to in-wall rectangular ducting

I'd just get a length of rectangular 3-1/4 x 10 duct, capped on both ends, and connect to it low and high with starting collars. Seal things up nicely with silicone caulk or foil tape. ...
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  • 104k
4 votes
Accepted

Is the ventilation in my utility closet a construction mistake?

The furnace has the intake and exhaust of a sealed unit but the water heater is an old style open burner. The water heater requires the outside vent. The size of the vent is based on the BTU rating of ...
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  • 95.8k
4 votes
Accepted

Can I ventilate attic space using wall vents?

Gable end vents were a common approach to attic ventilation decades ago, but those aren't nearly large enough. Gable vents don't provide the airflow that a soffit-to-ridge system does (via convection ...
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  • 104k

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