How To Install Soffit Vents | Do It Yourself

Recent Articles

Should I Add Additional
 Insulation To My Walls?

Should I Insulate
 The Wall Plates?

Blowing Insulation Over 
Recessed Lights

Ventilated Attic 
Access Covers

Insulating An Attic 
With No Access Hole

Adding Additional Attic 
Insulation Over Fiberglass Batts

Skylight Covers To
 Reduce Air Infiltration

Do I need a vapor barrier?

Insulating Over Knob and
Tube Wiring

Vapor Barriers On
Basement Concrete Walls

Insulating The Ridge Of
Cathedral Ceilings

Adding Insulation 
Over Vermiculite

How To Install Soffit Vents

Jeremy N. of Plano, TX wrote:

Hey Itchy,

My house has no lower ventilation. How do ya'all install soffit vents?

Soffit vents are used for lower ventilation of the attic. These are simple to install and I will guide you through it.

First you need to measure your attic to determine the square footage. Generally speaking you will need one foot of lower ventilation for every 150 square feet of attic floor (check with your local building department). Next, you will need to select the type of soffit vent you wish to install. These come various sizes and can be painted to match your home's exterior once installed.

Before installing the soffit vents you need to make sure all insulation has been moved from the area. A soffit vent clogged with insulation serves no purpose. Grab a light, a dust mask, goggles and climb on into the attic. Inspect the area from the exterior wall plate to the fascia. If you find any insulation on the soffit overhang it needs to be removed.

Installing Soffit Vents:

OK. You have determined how much ventilation you need and have selected the soffit vents you'll be installing. Use a chalk line and make two parallel lines on the soffit overhang. They should be set to be in the middle of the overhang with a distance between the lines equal to the width of the soffit opening. Don't set the chalk lines to the width of the entire soffit vent or you won't have anything to attach the vent to after you make your cut. Choose locations for the vents to be placed, making sure they are between the rafters. Measure the length of the soffit vent opening. Using a carpenter's square mark the holes to be cut using the length and width of the soffit vent opening.

Now you have the areas marked. Next you need to cut the holes. I prefer using a reciprocating saw but you could use a circular saw. When cutting the holes make sure you are careful around any windows and be sure to wear a dust mask and goggles.

Soffit vents come factory made with screw holes. Apply a thin bead of caulk to the flange area of the soffit vent. Attach the vent to the soffit using a drill and screws.

That's all there is to it. Paint can be applied to the soffit vents to match the home's exterior if you desire.

Related Tips and Advice:

How To Install Roof Vents

How To Install Gable Vents

How To Install Insulation Baffles

New Page 1