Exterior doors should be airtight. That's very important for home energy efficiency.
Pay attention to the gap at the bottom of your exterior doors (front, back and side doors). That gap is often a major air leakage area, and should be fixed.
Typically, the gaps at the sides and top of your doors aren't important sources of drafts and air leakage; but they can still be important for home energy efficiency.
Before replacing door seals
Damaged and misaligned weatherstrips can be an important cause of energy waste. Doors should be both airtight and watertight.
Extended use may cause door weatherstripping to fail, but there are factors that should be addressed before replacing the seal. Check for the following:
- Make sure that the door is not warped, with non-parallel jambs, or improperly installed, and see if the threshold is well adjusted. This type of problems should be fixed before the installation of a new weatherstrip.
- Fix possible problems with stripped hinge screws or loose screws; screws should be tightened, and stripped screw holes repaired. Otherwise, it will cause the top part of the door to lean away and be a source of problems, including wear and improper fit of the weatherstrip;
- Make sure that there isn’t problems related with the foundation settling, termites and rotting.
Also take into account that most modern door weatherstrips have compression and steel magnetic weatherstripping, and that it may not be possible to find an exact match to the weatherstrip of older doors (tack on vinyl, metal weatherstrip).
There are many cases – excessive wear, poor fit… - where replacing the entire door is the best option.
1- Door bottom weatherstrips
Types of weatherstrips for door bottoms
Basically there are two types of weatherstripps for door bottoms:
1) door sweeps and...
2) door bottom weatherstrips (door shoes, finned door bottoms, interlocking channels...).
Prior to weatherstripping your doors, fix any possible problems with them. Examine the doors, and tighten their screws, hinges and strike plates, if necessary.
Door bottom weatherstrips (and some door sweeps) require also a threshold; that's important to seal the gap, and to allow the door to swing without touching the floor covering.
Prefer a vinyl sweep. Avoid adhesive door sweeps.
Common door sweeps are made from aluminum or stainless steel and have a brush of vinyl, plastic, felt or sponge; some are retractable - to avoid dragging.
Typical door sweeps are easy to install. They just have to be mounted (using screws or nails) on the door's interior side (in the case of in-swinging doors) or on its exterior side.
Be careful not to have it too low; it will cause the door to drag which will wear down the sweep. Ideally, the sweep should rest lightly on the floor (or on the treshold) when it is in the closed position.
Follow the manufacturer's installation instructions.
Door Bottom weatherstrips
There are several types of door bottom weatherstrips, all with the same basic mechanism, shown in the image at left; once installed the bottom weatherstrip closes the gap between the threshold and the door.
Since they do not hang down like sweeps, properly installed door bottom weatherstrips will never drag on the floor covering, which increases their lifespan. Besides, their design is also much more effective at sealing.
There are anyway different types of door bottom weatherstrips, with different prices and different levels of effectiveness...
Door Shoe weatherstripping
Door shoe weatherstrips use a vinyl insert, or sponge rubber tubes. See image.
Prices are lower than those of interlocking weatherstrips, shown below. Vinyl inserts are replaceable.
Interlocking metal weatherstrips are perhaps the best bottom weatherstrip system (see image at left).
They are very durable and very effective at air sealing, but relatively expensive. The alignment of the interlocking channels is critical, and requires professional installation.
Finned door bottom weatherstrips
Finned door bottom weatherstrips are easy to install, and typically inexpensive.
It involves a vinyl strip with fins, designed to contact the threshold. Since it uses several fins, damages in a fin will not affect the sealing ability of the product.
Thresholds with Embedded weatherstripping
Door thresholds may have an embedded weatherstrip, which contacts the edge of the bottom of the door (image below).
This weatherstripping system operates without door bottoms and sweeps, but attracts more dirt and is more easily damaged by foot traffic and wear.
2 - top and side door Weatherstrips
We can distinguish two main types of weatherstrips for the top and sides of the doors:
1) stop-mounted weatherstrips, easy to install and inexpensive and...
2) jamb-mounted weatherstrips, often more expensive and difficult to install (and, in most cases, also the most effective).
Stop-mounted weatherstrips should be very flexible, to better respond to the seasonal expansion and contraction of doors, due to temperature and humidity changes.
They include silicone bulb, vinyl flap and fabric-covered polyurethane weatherstrips.
They are a lot better than foam and felt tapes, and self-adhesive plastic weatherstripping in general. Self-adhering weatherstripping are very simple to install, but tends to fail over time. And most of them may never seal well.
Jamb-mounted weatherstrips tend to last longer than stop-mounted weatherstrips.
Bronze V-seal weatherstrip is one of the most common jamb weatherstrips, and can be a very good choice. The only downside is that it isn't easy to install. It requires some skill, and experience - and a minimum space between the door and the door jamb (at least 1/8 inch/3 mm).
Typical self-stick V-strips are easy to install. Just clean the edge of the door, carefully, removing unwanted grease or residues of paint. Then, cut the V-trip to match the width and the height of the door. Peel off the backing of the V-strip at one end and press the material in place, peeling and pressing toward the other end. Follow the manufacturer’s instructions.
Other jamb-mounted weatherstrips
Magnetic weather-stripping is excellent for duration and effectiveness. These weather-strips are very common on new doors, but are difficult to install in existing ones.