How To Install B Vent Through Walls? [Instrallation Instructions]

Want to decorate your new house or want to re-design the house by installing new systems to your house? In this case, a fireplace is always an exclusive choice to have. 

And if you have already selected the b vent as your one, you need to follow proper rules of “how to install B vent through walls” to avoid any type of damage, leakage, or slippage in your wall, roof, or at any corner of the ceiling.

B vents being a natural vent system absorb air from inside to combust and vents it outside. While searching for realistic, large flames, B vent is a better choice. This is how it maintains a good ambient in your room also.Though it needs some techniques to follow while installing, which are described here step to step. So let’s follow-

How To Install B Vent Through Walls

How To Install B Vent Through Walls –

The Procedure

The Procedure of Installing B Vent Through Walls

Estimated cost: $80-$150 (though it may vary according to your house designation or length varieties)

Total time required: approximately 1.5-3 hr. ( depending on size, number of support, labor investment)

Tools required: 

alongside the pipe and chimney, you need – 

  • Screw
  • Cutter
  • Drilling machine
  • Circular saw

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Plan your installation by drawing a sketch of the area that you will be working on. Make sure to include the size and shape of the vent, as well as the location of any electrical wiring or other obstructions.



Placement is critical, and must be done correctly to ensure efficient air combustion. Vent placement should be sloped so that the air is directed downwards and away from surrounding surfaces.

Draw Sketch

To ensure correct placement, use a sketch to follow the contours of the area. Remember that you want the vent to be sloped and positioned so that air is directed downwards and away from other surfaces.

Ensure Air combustion

Ensure air combustion by setting up an apparatus that will generate heat and smoke. This can be done using a stove, fireplace, or open flame.

Make a Slope

Make a slope by cutting a piece of wood that is the same size as the vent and attaching it to the side of the vent. This will help direct air downwards and towards the vent

Termination of Area

When installing an area vent, make sure to terminate it by cutting the wire or tubing. This will prevent debris from entering the vent and blocking its operation.


Lastly, you’ll need to make sure that the area around the vent is enclosed so that airborne debris doesn’t get in the way.

Steps On Installing B Vent Through Walls

Steps on Installing B Vent Through Walls

Local Regulations

Local Regulations

First, do acknowledge the local code and venting practices of your area. As if the placement requires more appliances, then you may need proper adjustable places.



Read through the manufacturer’s instructions to have a clear view of the correct positioning of the unit. This will also let you know if you need some connectors or venting materials only.

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How to Mark Your Tools – A Complete Guide

Sketch your plan. It will help you to adjust the system on point without making errors while positioning.

Support Assembly

SketchingSupport Asembly

Frame a 4 sided hole in the floor with a dimension of 2 inches larger than the vent’s outer diameter. Place the support assembly on the upper side of the hole and support band on top. Spacers ensure complete clearance of combustibles.

Nail the support assembly to the floor with 3 three-inch nails on each side.

Lower the first vent section through the support band and clamp the band to hold the vent at the desired height. Also, secure the band to the vent’s casing with four 8*3/8 inch long sheet metal screws.

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The support assembly will support up to 60 inches of the vent. If the vent exceeds this height, then use additional support assemblies.

Assemble Vent Section-

Assemble Vent Section

Install the additional vent length above the first one. Fit the female end over the male collar and give it a clockwise twist to fasten.

Firestop Spacers

Firestop Spacers

Where your vent passes through a floor or roof, there a firestop is required. Place the spacer around the vent with the spacer brackets towards the framed hole.

Push the firestop flat and fasten it by four nails to the framing. You should seal the vapor barrier to the firestop or the ceiling using an appropriate caulking compound.

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Attic Insulation Shield

Attic Insulation Shield

It is needed where the vent passes into an attic space.

Where there is the height for this shield, it is permissible to construct an enclosure with a 1-inch air space clearance to the outer pipe.

The opening must be framed at 1 inch of clearance to the outside casin of pipe with framing material of the same dimension as the ceiling.



Assemble the support and bolt it to the wall with 4-inch anchors adjustable to the wall material.

Lower the length of the vent through the support and twist it to lock to the tee. Do tighten the support’s clamp band and further secure the vent with four 8*3/8 sheet metal screws into the vent case.

Continue with additional vent lengths as necessary. Install wall bands at least at every 6 inches of vent rise.

Roof Assembly

Roof Assembly

While the vent protrudes through, slide the flashing down until its base sits on the roof.

Place the upper side of the base under the shingles and the lower side over the shingles.

Slide a storm collar down to the flashing top and seal with silicone

off the top of the vent with a rain cap.

Wall Penetration

Wall Penetration

Cut a hole in your wall where you intend to pass the vent. Frame the square hole dimensions 2 inches larger than the outside diameter of your vent.

Now install firestop spacers inside and outside both of the openings. Fasten them with 1-inch nails at each corner. It should be a minimum of 1 inch.

Now, through the firestop spacers, place a length of the vent. 

From the outside of the building, connect a 90-degree elbow or a tee to the horizontal vent.



The vent must be enclosed by a chase at least to the roofline. Also, the enclosure must consist of a 28 gauge sheet metal box spacing 2 inches from the vent.

The chase must be caulked to prevent moisture entrance. 

Final words

Even after learning the steps, you must first learn and execute whatever your local authority regulations show about how to install B vent through walls.

It is a tricky procedure, and you should not make any blunders while installing this. So if you are unable or not comfortable with the installing process, please seek professional help to have a secure setting.


Is It Possible To Install The B Vent Horizontally?

No. it is not compatible with the appliances to place horizontally.

The only thing you can do horizontally with this is to terminate the vent pipe in a horizontal position.

Are Fireboxes Necessary?

No, it is not actually. But if an owner wants, he can use it to combust more air from the corners of the room. It will be a helpful addition indeed.

Can I Use This With Oil Or Coal-Fired Equipment?

Not. you should use a wood-burning vent system for this case

Can B Vent Touch Drywall?

Cannot. Vent should not come into contact with drywall as this can cause damage and impede the vent’s operation.

Do You Screw B Vent Together?

This can be a difficult question to answer, as it largely depends on the type of B vent you are using and how it was installed. In general, however, it is generally recommended that B vents be screwed together in a tight seal to protect the duct from the surrounding environment.


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