Measuring windows for blinds sounds simple. It almost never is — especially in Vancouver, where older character homes have non-standard window dimensions, new condos have floor-to-ceiling glass with unusual proportions, and strata buildings have exterior-facing requirements that affect how blinds must be mounted.
This guide walks through exactly how to measure your windows for blinds — covering inside mount, outside mount, bay windows, and the specific considerations that come up frequently in Vancouver homes. Get the measurements right, and the rest of the process is straightforward.
The First Decision: Inside Mount vs. Outside Mount
Before you take a single measurement, you need to decide how your blinds will be mounted. This decision affects how you measure, what you order, and how the finished result looks.
Inside Mount
An inside mount blind sits within the window frame recess. The hardware attaches to the inside of the frame, and the blind drops down inside the opening.
Inside mount is generally the preferred aesthetic in Vancouver homes — it looks clean and architectural, doesn’t cover the window trim, and suits the minimal design language common in newer condos and renovated character homes.
Requirements for inside mount:
- Minimum frame depth of 1.5 inches (some blinds require more — up to 3.5 inches for deeper products)
- The frame must be level and square — significantly out-of-square frames will show gaps
- The opening must be free of obstructions like handles or cranks that would block the blind
Outside Mount
An outside mount blind attaches to the wall or window trim above the opening, and hangs in front of the glass rather than inside the frame.
Outside mount is the right choice when:
- The frame is too shallow for inside mount
- The frame is significantly out of square (common in older East Vancouver and Kitsilano homes)
- You want the blind to cover more than just the glass — overlapping the trim creates a larger visual field and can make windows appear taller or wider
- You want maximum light blockage — outside mount allows wider overlap on all sides
How to Measure for Inside Mount Blinds
You’ll need a metal tape measure (fabric tapes can stretch and give inaccurate readings), a notepad, and ideally a helper for large windows.
Step 1: Measure the Width
Measure the inside width of the window frame at three points: top, middle, and bottom. Window frames in Vancouver — particularly in homes built before 1980 — are often not perfectly parallel. Record all three measurements and use the smallest of the three. This ensures the blind will fit at the narrowest point.
Do not round up. Measure in fractions of an inch (eighths or sixteenths). When you order a custom blind, the manufacturer will typically deduct a small clearance amount (usually 1/4 inch to 3/8 inch) from your width measurement to ensure the blind fits and operates without binding.
Step 2: Measure the Height
Measure from the top of the inside frame to the window sill at three points: left side, centre, and right side. Again, use the smallest measurement. For blinds without a sill (pass-through windows or windows flush to the floor), measure to where you want the blind to end.
Step 3: Check Frame Depth
Measure the depth of the frame from the front face to the glass (or to any obstruction like a window crank). Compare this to the minimum depth requirement for the blind type you’re considering. Most roller shades need 2–3 inches. Faux wood blinds typically need 1.5–2 inches. Honeycomb blinds vary by product.
How to Measure for Outside Mount Blinds
Outside mount measurements are more flexible because you control the coverage area — but they require a few additional decisions.
Step 1: Decide Your Overlap
For outside mount, you typically want the blind to extend beyond the window opening on all sides to block light gaps and create a finished look. Standard practice is:
- Width: extend 1.5–3 inches beyond the frame on each side (so add 3–6 inches total to the frame width)
- Height: extend 2–4 inches above the frame (to allow mounting hardware above the window), and reach to the sill or 1–2 inches below it
For rooms where light blockage is critical — bedrooms facing east, or rooms on Vancouver’s frequently overcast but occasionally bright winter mornings — err toward more overlap on all sides.
Step 2: Measure the Mounting Area
Confirm there’s enough flat wall or trim surface above the window for your mounting brackets. Most brackets need at least 2 inches of surface. Check for obstacles like picture rails (common in character homes across Vancouver’s West Side), electrical boxes, or deep window trim.
Step 3: Record Your Finished Size
Unlike inside mount, outside mount measurements represent the actual finished size of the blind — there’s no deduction. What you measure and order is what you get.
Not confident in your measurements? Passion Blinds offers free in-home measurement across Vancouver — we handle the measuring so you don’t have to. Call 604-727-7037
Measuring Specific Window Types Common in Vancouver
Condo Floor-to-Ceiling Windows
Floor-to-ceiling windows in Vancouver condos present two specific challenges: height and levelness. Many concrete high-rises have floors that aren’t perfectly level, which means a blind hung from ceiling-height may show a visible gap at one end of the sill.
For these windows, professional measurement matters more than for any other window type. We use a laser level to account for floor variation and ensure the blind, when installed, sits visually level even if the floor isn’t. This is a step that DIY measurement frequently misses.
Bay Windows
Bay windows require each angled section to be measured independently. The three (or more) panels of a bay window are rarely identical in width or square, and the angle between them affects how the blinds will look when open.
Bay windows typically look best with inside mount blinds in each individual section, with the blinds raised to a consistent height when open. Attempting to treat a bay window as a single wide blind is almost always a mistake — the mechanics don’t work cleanly across the angle.
Older Character Home Windows
Vancouver character homes — particularly in Strathcona, Mount Pleasant, Grandview-Woodland, and along the Broadway corridor — often have original windows that are significantly out of square. Sills may slope inward or outward. Frame widths vary top to bottom by half an inch or more.
For these windows, outside mount is often the cleaner solution — it bypasses the out-of-square frame entirely and creates a consistent, flat presentation. Inside mount on severely out-of-square frames almost always shows light gaps that no amount of deduction can fix.
Arched and Specialty Windows
Arched windows, round-top windows, and other specialty shapes in Vancouver heritage homes require either custom-shaped blinds or a combination of a standard blind for the rectangular lower section and a fixed (non-operating) fabric or cellular shade for the arch above. These applications require an in-person assessment — there’s no reliable way to measure for these remotely.
Common Measuring Mistakes — and How to Avoid Them
| Mistake | What Goes Wrong — and the Fix |
|---|---|
| Measuring only once per dimension | Windows aren’t perfectly parallel — always measure width and height at three points each and use the smallest reading |
| Using a fabric tape measure | Fabric stretches — always use a rigid metal tape measure for accurate readings to the nearest 1/8 inch |
| Forgetting frame depth for inside mount | The blind won’t fit or won’t operate — check minimum depth requirements for your chosen blind type before committing to inside mount |
| Not accounting for handles or cranks | Crank-operated windows are common in Vancouver condos and character homes — ensure there’s clearance for the blind to operate without hitting the mechanism |
| Measuring in centimetres for a Canadian-market product | Most blind manufacturers in Canada work in inches — confirm the unit of measurement expected before ordering |
| Assuming all windows in a room are the same size | Even windows that look identical in the same room often differ by 1/4 to 1/2 inch — measure every window individually |
When to Skip the DIY Measuring
For most standard windows in newer Vancouver homes and condos, following the steps above will give you accurate measurements you can order from confidently.
Book a professional measurement instead if:
- You have floor-to-ceiling windows where levelness matters
- Your windows are significantly out of square (older character homes)
- You’re dealing with bay windows, arched windows, or any specialty shape
- You’re ordering motorized blinds — where a misfitted blind means the motor has to work against the frame
- You have strata requirements that specify exact coverage dimensions or clearances
A professional measurement takes 30–45 minutes for a typical Vancouver home and eliminates the risk of ordering a blind that doesn’t fit — which means you’re not waiting through a second production and delivery cycle.
Frequently Asked Questions
Q: Do I need to provide measurements when booking a consultation with Passion Blinds?
A: No — that’s what the consultation is for. We come to you, measure every window precisely with professional tools, and provide a quote based on accurate numbers. You don’t need to measure anything in advance.
Q: What if I measure wrong and the blind doesn’t fit?
A: If you’re ordering through a professional installer using their measurements, fitting errors are their responsibility to resolve. If you’re self-measuring and ordering direct, most custom blind manufacturers have specific policies on remakes — check before ordering. This is one of the clearest advantages of using a local installer: measurement accuracy is guaranteed.
Q: My Vancouver condo windows have an aluminum frame and no real wood sill. How does this affect measuring?
A: Aluminum-framed windows in Vancouver condos are typically more consistent and square than wood-framed windows in older homes, which makes measuring easier. However, the frame depth on aluminum windows is often very shallow — sometimes only 1 inch — which may rule out inside mount for certain blind types. We’ll confirm depth requirements when we assess your windows.
Q: Can I measure windows I want to cover with different blind types the same way?
A: The measuring process is the same, but the deductions and clearance calculations differ by blind type. When in doubt, take the raw measurements and let your supplier or installer calculate the order dimensions — they’ll apply the correct deductions for the specific product.
Get Your Measurements Done Right — for Free
Passion Blinds provides free in-home measurement and consultation across Vancouver, Burnaby, North Vancouver, Coquitlam, New Westminster, and surrounding areas. We bring samples, measure every window, and give you a complete quote on the spot — with no obligation to purchase.
Book your free measurement consultation → passionblinds.com | 604-727-7037