Improving the Energy Efficiency of Your Historic Building's Exterior Doors
You can improve the energy efficiency of your historic house or building by weatherizing your exterior doors. Exterior doors cause a lot of energy loss because they are opened and shut often. Weatherizing an exterior door is an easy procedure with one main objective: to stop air infiltration.
You have three options for weatherstripping an exterior door. All three options are effective, so you should choose the one that best matches your skillset.
Strip-Style Weatherstripping
In this photo a rubber edged, strip-style weather stripping is secured to the side of a door jamb. Source: Bob Yapp
The simplest and most effective way to weatherize an exterior door is to install strip-style weatherstripping. This type of weatherstripping is a long strip of either extruded aluminum or wood with a rubber-like tube gasket material attached along the edge of the strip. The strip is screwed to the jamb next to the door with the gasket edge touching the door on the top and both sides. In Wisconsin’s cold climate, rubber is not the best material for the gasket because it can get stiff in cold weather. The best gasket material for the Wisconsin climate is neoprene.
Aluminum strips are available in multiple colors to blend in with the color of your door. If you buy wood strips for weatherstripping, you should paint them to match your door. Paint the wood strips before you install them and touch up the paint as necessary after installing them.
Follow these steps to install strip-style weatherstripping:
- Measure the width of your door frame inside of the door jamb at the head (top) of the door jamb. This is the measurement you will use for the head piece of weatherstripping that you will install at the top of the door frame.
- Cut the strip of aluminum or wood to the length you need for the head piece. You can cut aluminum strips with either a carbide blade in a power miter box or a hack saw. You can cut wood strips with a power miter box, hand miter box or even a saber saw. Cut the head piece to fit snuggly inside the jamb.
- Set the head strip in place and screw it to the jamb so the gasket edge is just touching the door when the door is closed and latched.
- Measure the two side pieces from the threshold to the head piece you just installed. The threshold is the floor beneath the bottom edge of the door. Cut both strips to the correct length. Screw each piece to the jamb so the gasket edge is just touching the door when it is closed and latched.
Spring copper weather stripping is sold in a coil such as seen in this photo. Source: Bob Yapp
Installing spring-style weather stripping to the side of a door jamb is done in the same manner as strip-style weather stripping. Source: Bob Yapp
Spring-style metal weather stripping installed. Source: Bob Yapp
Spring Metal Weatherstripping
Spring metal weatherstripping consists of coils or rolls made of brass, bronze, stainless steel or copper. The basic spring style is available at most hardware stores and lumber yards.
The spring strips are nailed or screwed into the door bed where the door rests when closed.
When the door is closed, the metal coil or roll bends slightly and flexes against the edges of the door.
Follow these steps to install spring metal weatherstripping:
- Measure the width of the inside of the door frame at the head (top) of the jamb.
- Cut the strip of metal to the length you need for the head piece. Use tin snips to cut spring weatherstripping to the correct length. Cut the head piece to fit snuggly inside the jamb.
- Set the head strip in place. Attach the head piece to the head jamb using the nails or screws that came with the strip. Attach the head piece with the bent flexible edge facing toward the door stop molding.
- Measure the two side pieces from the threshold to the head strip you just installed.
Cut both strips to the correct length. Attach each piece to the door bed with the bent flexible edge facing toward the door stop molding.
Threshold Weatherstripping
There are many variations on the door sweep as seen in this photo. Remember for Wisconsin weather the best sweep material is neoprene. Source: Bob Yapp
There are many types of threshold weatherstripping products on the market. The easiest type to install is the door sweep.
A door sweep installed and painted to match the door. Source: Bob Yapp
A door sweep is a metal strip with a rubber-like or plastic fin attached to the edge. In Wisconsin’s cold climate, neoprene is the best material for the fin. The door sweep is attached just above the bottom edge of the door so the fin just touches the threshold. When the door is shut, the fin prevents air from entering under the door.
If the door swings in, you should attach the door sweep to the interior side of the door. Do the opposite if the door swings out.
Door sweeps are available in multiple colors to blend in with the color of your door. To install a door sweep, you should follow the instructions for cutting and installing strip-style weatherstripping.
The information presented here is not intended to provide comprehensive technical advice or instructions on solving historic preservation issues. Any information contained or referenced is meant to provide a basic understanding of historic preservation practices. Read full disclaimer.