The investment in a new door can cross into the thousands. For such an amount, mistakes like having too much gap between the door and floor can be painful, but what is the standard gap to aim for during installations?
The standard gap between the floor and an interior door is 2 in (5.08 cm) for unfinished floors and ¾-½ of an inch (1.90-1.27 cm) for finished floors. The exact measurement will depend on your floor type. Exterior doors shouldn’t have any gaps from the floor to maintain a home’s energy efficiency and safety.
The rest of the article will look at all you need to know about maintaining the right floor height when mounting new doors. Watch out for tips on what to do when you inadvertently end up with too much gap post-installation.
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When it comes to installing interior doors, your focus should be on ensuring that the door opens without scraping past the floor material. This typically means maintaining a gap of no more than half an inch (1.27 cm) for such finished floors. Depending on the floor material, the gap can be smaller at ¾ of an inch (1.90 cm).
Any installation where the gap is up to an inch (2.54 cm) wide for a finished floor is a poor job from the installer. Similarly, the door will leave scuff marks on the floor when you swing it open.
Both situations are common mistakes you’ll find in unprofessional door installations. However, you’re more likely to find doors with gaps wider than necessary because doors that are too close to the floor are easier to catch.
For unfinished floors, the gap allowed can be as wide as 1.5-2 in (3.81-5.08 cm). There’s a bit more flexibility here because the flooring material installed will likely be designed around the door to ensure a perfect fit. Once the floor is finished (or cover installed), you’re still likely to end up with ¾-½ of an inch (1.90-1.27 cm) gap.
Exterior doors come with sills that must be fastened to the floor. The installation has to be airtight, so there’s no gap allowed. Unlike the interior variants, the bottom of an exterior door has to be flush on the sill. It doesn’t go directly to the floor as it’s the sill that has to be in contact with the floor.
Since the sill has to be fastened tightly to the floor, you can’t have any gaps. In the rare case that you buy an exterior door without a sill, the installation should only allow just enough gap to avoid scraping against the floor when the door swings open.
Exterior doors play a pivotal role in the energy efficiency of any home. Allowing gaps between the door and the floor increases the chances of losing warm or cool air to the outside. It also means insects, worms, and small snakes can crawl into the home undetected.
Interior doors need gaps (also known as undercuts) for a couple of reasons. First, the space makes opening the doors easier, as I’ve mentioned above. Secondly, the gap acts as a return air path for your heating system.
Most residential forced-air units have a designated supply route to each room, but there’s a central return. This means that the air from each room has to go back to the HVAC to recirculate properly. If that doesn’t happen, the result will be negative pressure at the unit and positive pressure in the room.
So, the gaps between interior doors and the floor make opening and closing the doors easy and help maintain your HVAC system’s efficiency.
If you’ve noticed that your door has too much gap between the bottom and the floor, there are a few things you can do:
If you’ve noticed the problem shortly after the installation, you can call back the installers and request a height adjustment. Of course, this only works if you have some sort of warranty agreement in place or if the installers are open to such adjustments even after collecting full payment.
If they agree to make the change, be sure to point out how much gap you want between the door and the floor and confirm it when they’re done.
If your arrangement with the installers is such that they can’t come back to work on the door, you can fix the gap by simply adjusting the alignment.
You’ll need a screwdriver to loosen the screws a bit for the adjustment. If you hung the door a long time ago, you might need to replace old screws with newer and larger ones to ensure the door won’t shift again after adjustment.
When adjusting the door is impractical, a door sweep is an easier way to fix the gap. These small attachments are affixed to the bottom part of the door to reduce or eliminate gaps.
When choosing door sweeps, you can go with the bristle sweeps or the rubber seals. The bristle sweeps come with a brush tip, while the rubber seals look like a rubber curtain without any bristles. Any of them can reduce the gap between your door and the floor, but the rubber curtain is usually more effective at keeping out pests.
Draft stoppers are also nifty attachments like door sweeps, but they serve the dual function of covering the gap between the door and the floor and keeping out cold or hot air.
The Suptikes Door Draft Stopper (available on Amazon.com) is a good example here. It can fit on both interior and exterior doors, and it’s fairly easy to install. The Holikme Twin Door Draft Stopper (available on Amazon.com) is an alternative worth mentioning. It’s great for interior doors and can keep out air from both directions. However, it’s a bit less flexible when it comes to managing the gap.
Whichever option you choose, you can be sure of reducing the gap between your door and the floor easily without fiddling with parts of the door.
Generally, you should consider the floor material when measuring the gap between the door and the floor. If you’ve got a carpet, laminate, or hardwood floor, your measurement should be from the bottom of the door down to the surface of the floor material.
So, you’re leaving a ¾-½ inch (1.90-1.27 cm) gap between the door and your carpet, laminate, tile, or hardwood floor. Remember, your focus should be on ensuring that the door can swing open or close without getting stuck.
Don’t hesitate to widen the gap if you think it’s necessary. For example, some heavy or fluffy carpets may need the gap to be as high as an inch (2.54 cm).
The standard gap between door and floor will come down to your floor type. However, the gap between the floor and most interior doors ranges from ¾-½ in (1.90-1.27 cm). It could be a bit higher if the floor type or cover demands it. Exterior doors typically don’t need any gaps because they are vital for maintaining your home’s temperature.
If you’re installing a new door as a DIY project, it’s best to go with pre-hung options as they’re easier to install. If the DIY process is too challenging for you, don’t hesitate to call in a professional.