Blinds are a great investment for homeowners because they provide so many benefits. Not only do they provide protection from the sun, but they also add to the aesthetic, increase efficiency, and offer more privacy. In order to get the most out of a new blinds installation, homeowners need to make sure that they are installing the right size.
If they are too small, they may let in too much light or make it more difficult to heat and cool the room. If they are too large, they may end up looking awkward and bring down the appearance of the room. For those reasons and more, it’s important that homeowners know the best way to measure for their new blinds.
Fortunately, the process doesn’t have to be difficult. Instead, homeowners can follow a few simple steps to find the perfect fit for their windows. In this guide from BlindQuest, homeowners will learn the best methods for measuring two different types of blinds: inside mounts and outside mounts. Keep reading to learn more.
Not sure what type of blinds you’re even shopping for yet? Our post on different types of blinds is a great place to start before you pull out the tape measure.
Getting the width right is the first step to a clean, seamless blind fit.
Why Getting Your Measurements Right Matters More Than You’d Think
It’s easy to assume that blinds are forgiving on fit. They’re not. Even being off by a quarter inch can mean gaps around the frame that let in light or, on the flip side, blinds that simply won’t close all the way. For homeowners in the Troy and Edwardsville area, where summer sun can be intense, that matters.
Beyond light control, the U.S. Department of Energy notes that windows account for 25 to 30 percent of residential heating and cooling energy use. Well-fitted window coverings help offset that significantly, but only when they actually cover the window properly. A gap on either side is basically a gap in your insulation.
Getting measurements right also means fewer returns, no rushed re-orders, and a finished look that actually looks finished. That’s the goal.
Measuring for Inside Mount Blinds
As the name would imply, an inside mount blinds installation takes place within the window frame or casing. Many people love this style of blind mount because it is very sleek. It can give any space a clean look, and it also allows the details of the window frames to shine through because it won’t cover any moldings.
Since the size is limited by the size of the frame, it’s important to make sure the blinds aren’t too big, especially if they are custom-made. In order to make sure that the blinds fit perfectly for a seamless installation, homeowners should follow these steps:
- Measure the window frame’s depth. Measuring for a blind installation isn’t just about making sure the blinds fit within the frame. It’s equally as important that the frame be deep enough to accommodate the mount itself. Homeowners can refer to their mounting requirements to see the minimum depth needed for their preferred blind style.
- Measure the width of the window opening. Homeowners should take three measurements: the top, middle, and bottom. From there, they will need to select the narrowest point as this will dictate the maximum width of the blinds. If vertical or solar shades are being installed, only the top measurement is needed.
- Measure the height of the window opening. Measurements for the height should be taken in three places as well to get the best fit for roller shades, vertical blinds, solar shades, and sheer shades. Homeowners will select the smallest number from the left, center, and right. For any other style of blind, the longest number should be used.
- Order the exact opening size. It’s not necessary to make deductions from those measurements. The factory will take their own deductions during the manufacturing process.
- Double-check the measurement format. It’s important that the measurements be given in width-by-height format. If the numbers are reversed, the blinds won’t fit!
Height measurements should be taken at three points: left, center, and right: to account for any unevenness in older window frames.
Measuring for Outside Mount Blinds
Some homeowners prefer the look of blinds that are mounted outside of the window molding. This can make windows look longer or wider, and they provide exceptional light control and privacy. They are also a good alternative if the depth of a window casing won’t allow for an inside mount.
Follow these steps to get the measurements for an outside mount blinds installation:
- Measure above the window. There should be at least 2 inches of flat space above the window to accommodate the mount.
- Choose the location for the headrail. The mount can be installed directly on the wall or molding if there is enough flat space.
- Measure the width. The amount of space to be covered is ultimately up to the homeowner, but it’s recommended that there be at least 1.5 inches of overlap on either side of the window.
- Measure the height. To determine the height, measure from the location of the headrail to where the bottom of the blinds will be. Homeowners can choose to measure to the sill or beyond, but if the window sill protrudes, that should be the lowest point.
- Don’t take deductions. Again, this is something the manufacturer will account for.
- Use proper format. Measurements should always be given in width by height.
Inside Mount vs. Outside Mount: A Quick Comparison
Not sure which direction to go? Here’s a side-by-side look at how the two mount types compare across the factors homeowners usually care most about.
| Factor | Inside Mount | Outside Mount |
|---|---|---|
| Look | Clean, built-in appearance | Larger, more dramatic look |
| Light Control | Good, with some edge gap | Better, with overlap on all sides |
| Frame Visibility | Moldings stay visible | Moldings covered |
| Depth Requirement | Frame must meet minimum depth | No depth requirement |
| Window Size Appearance | True to actual size | Can make windows look larger |
If your windows have beautiful trim or craftsman-style detailing, inside mount is almost always the better call. For shallow frames or rooms where you want to maximize the sense of height or width, outside mount gives you more flexibility. Our post on shades vs. blinds for your Edwardsville home also covers how the style of window treatment plays into fit decisions.
Common Measuring Mistakes (and How to Avoid Them)
Even careful homeowners run into a few of the same pitfalls. Here are the ones we see most often, and exactly what to do instead.
| The Mistake | The Fix |
|---|---|
| Only measuring once | Windows aren’t always perfectly square, especially in older homes throughout the Metro East area. Always take three measurements for both width and height, then use the narrowest or shortest as your guide for inside mounts. |
| Skipping the depth check | For inside mounts, the headrail needs room to sit inside the frame without sticking out. Different blind styles have different depth requirements, so check those specs before ordering anything. |
| Using the wrong measurement format | Width always comes before height. Swapping those numbers is one of the most common errors and one of the most costly: the blinds still get made, just wrong. Double-check before you submit. |
| Measuring the old blinds instead of the window | Old blinds might have been measured incorrectly the first time around. Always measure the actual window opening, not whatever is hanging there now. |
Want to go deeper on a specific product type? Our guide on how to measure for mini blinds walks through the details for that particular style.
Learn More About Getting the Perfect Fit for a Blinds Installation
Homeowners who are worried they won’t get the right measurements don’t have to stress. The professionals of BlindQuest can come and measure windows to ensure the best fit for their products. To request a design consultation, simply call or submit their online form. Customers can also schedule an appointment to see their showroom!
Our team serves Troy, Edwardsville, Glen Carbon, Maryville, O’Fallon, Highland, and the surrounding Metro East communities. If you’d like help selecting the right window treatments for your space, contact our team to get started.
Ready for a Perfect Fit?
BlindQuest offers on-site consultations across the Metro East area. We’ll measure your windows, walk you through your options, and handle the installation from start to finish.
