A bathroom vent is necessary and it makes your bathroom fresh and hygienic. Most of the bathrooms have bathroom fans installed and they are vented through the wall because it is the easiest option.
But, if your bathroom is placed in the middle of your house or you don’t have the scope to vent through the wall, then you can vent the bathroom fan through the roof of the house.
Therefore, if you want to know how to vent a bathroom fan through the roof then you are at the right place. In this article, I am going to discuss the simple process so that you can follow them easily.
Table Of Content
- Venting A Bathroom Exhaust Fan Through The Roof with 5 Easy Steps
- Final words
Venting A Bathroom Exhaust Fan Through The Roof with 5 Easy Steps
Bathroom fan venting isn’t a new concept and managing the moisture generated in the bathroom is necessary to keep your bathroom’s wall mold-free. Many people allow the duct to emit into the attic. But, it can cause various problems in your attic’s surface and wall. So, let’s begin our windowless bathroom ventilation setting process…
You may also read this review: Best Exhaust Fan for Kitchen
Preparation Phase: Buying the necessary things
Before starting your journey, you need to buy or manage everything that you’re going to use. First of all, you need to purchase a dominant fan. I mean a fan that is ideal for your bathroom. To get the most appropriate fan for your bathroom you need to do some calculation.
Just multiply the area of the bathroom by 1.1. For instance, a 10 ft by 10 ft or a 100 sq.ft room need a 1.1 X 100 = 110 CFM(cubic feet minute) fan. Also, get a quiet fan. A sone rating below or equal to 0.5 will be perfect. You can easily find both the CFM and sone ratings on the fan box.
Also, you have to buy a 4-in flexible duct line or hose with insulation and a durable rust-resistant roof cap. Make sure that the cap has a little door inside it to keep the cold air blowing back into the bathroom when the fan is off. You may also buy foil duct tape and nails.
Step 01: Installing the fan inside your bathroom
If you successfully finish this step, you will complete 60 percent work of venting a bathroom fan. So, let’s start…
At first, you need to cut a hole inside the most suitable place of your bathroom ceiling. I would suggest that you make the hole in the exact middle part of the bathroom. To do that, measure the perimeter of the fan and draw a square or rectangle on that spot using these measurements.
After marking the area, get a jigsaw and begin your cutting process. Follow the previously drawn line to cut more precisely. After the first round of cutting, use a hammer and chisel to take out the waste materials from the hole.
Clean the hole carefully and make sure that you have made the hole through the attic of your house. Now, take the metal fan housing box and insert it inside the hole to check whether everything is okay. You can secure the fan housing on that spot by using some screws.
Step 2: Connect duct hose with fan housing
At this stage, go to the attic and grab the insulated flexible duct hose for connecting with fan housing. But before that, you should attach a 4-inch 90-degree elbow-shape hose to the fan housing’s outer port. It will give more stability to the setting and your duct line will have good support. Use the foil duct to adhere to it firmly.
Also, fix the cable connector part by removing the knockout hole. Finally, insert the fan into the fan housing and center it properly. Use a screw to fasten the fan on its position tightly and connect the flexible hose or duct line with the elbow.
Some people prefer to add while standing inside the bathroom. If you are a beginner, you should insert the fan from above. Yes, it is relatively hard but much safer compare to other options. Because, if anything goes wrong then the fan, fan housing, or the full setting can fall on your head causing serious injury.
Step 03: Making a roof vent hole
Now it’s time to make the bathroom exhaust fan roof vent hole. To do that, you need to reach the top of the roof.
Hold on! Before reaching there, you need to determine the position of the roof vent hole while staying inside the attic. Just insert a nail on your selected spot. Make sure that the nail is long enough and visible from above so that you can easily identify that position from the roof. Remember, you should not make the roof vent far from the fan.
After marking the position with a nail, use a good condition extension ladder to reach the top of the roof. Go near to the place where the nail came through and make a 4-inch round hole around the nail. You have to make the hole 4-in because the duct line is 4-inch wide. So, a bigger or smaller hole will create various problems.
For making the hole, you need to remove some roof sheets. If your roof has shingles covering, you should use a utility knife to get rid of them. Pry up the seal of nearby roof covering sheets to slide the vent hood with a flat pry bar.
Now, use a 4-inch round-shaped hole saw or hole cutter to cut the wood of the roof. If your roof is made of concrete, you need to use a diamond blade saw to do the task.
Step 4: Insert & Secure duct hose with roof vent hole
Once you make the hole properly, return to the attic and add a 4-inch metal sleeve to the edge of the insulated duct line. Use a crimping tool to crimp the sleeve to fit inside the duct line edge. Secure the connection with a foil duct tape. Now, insert this duct pipe into the roof hole.
Step 05: Placing the roof vent hood or roof vent cap
Again, climb the rooftop and hold the sleeve on its position and cut a couple of tabs on each side of the sleeve with snips or shears so that you can nail it to the roof. After nailing down the duct line, get the vent cap and add some bead underneath the cap and slide it under the shingles just above the hole.
Make sure the hole stays in the center position of the vent hood. Insert some roof nails to secure the vent cap on its place more firmly using a hammer. Lastly, add another layer of bead (sealer) over the edge of the hood and press the shingles to adhere to the vent cap strongly.
Here is the Best Visual Guide for Bath Fan Venting Through the Roof