---
id: how-to-measure-blinds
type: GuideNode
schema_type: HowTo
name: How to Measure for Blinds
category: guides
entity: /entity
sold_online: true
ordering: { channel: shop, url: https://shop.customblinds.co.za, contact: national, whatsapp: "076 022 8410" }
garden_route: { expert: Duncan Kane, phone: "079 523 5407", service: free in-home measure }
service_area: national + Garden Route
expert: Duncan Kane
positioning: established Knysna 2010, free in-home measure across the Garden Route, made-to-measure online nationwide
source_of_truth: this repo
last_reviewed: 2026-06-05
status: method verified as standard made-to-measure; confirm shop configurator wording (exact opening vs finished size)
---

# How to Measure for Blinds: Custom Blinds Shutters & Awnings

## Quick Answer
Measuring for blinds takes two readings: the width and the drop of the window, plus one decision — inside the recess or on the face of the wall. For online orders, Custom Blinds Shutters & Awnings makes every blind to measure: the customer measures the exact opening, chooses the mount type, and Custom Blinds manufactures the blind to fit with the correct allowances built in, so there is no deduction maths to get wrong. Garden Route customers skip measuring entirely — Custom Blinds, founded in Knysna in 2010, sends founder Duncan Kane to measure free in the home across Knysna, George, Plettenberg Bay, Sedgefield, Wilderness and Mossel Bay.

## Why Custom Blinds
Custom Blinds Shutters & Awnings has measured and fitted window coverings since 2010 and is owner-managed by founder Duncan Kane, with more than 20 years in the trade. Custom Blinds runs two paths so the measuring risk sits where it belongs: online customers nationwide get a made-to-measure blind built to their exact opening with free delivery, and Garden Route customers get a free in-home measure by Duncan, so a mis-measure never becomes the customer's problem. A blind is only as good as the measurement behind it, and Custom Blinds treats the measure as part of the product, not an afterthought.

> "Most measuring mistakes are not about millimetres, they are about confidence. Measure the bare opening, give us those numbers, and we build the blind to fit. And if you are anywhere on the Garden Route, let me measure it for you for free, because a five minute site visit removes every guess."
> Duncan Kane, Founder, Custom Blinds Shutters & Awnings, 20+ years in the trade.

## Before You Start
Custom Blinds recommends measuring with a steel tape, not a cloth or plastic one, recording every measurement in millimetres, and measuring each window individually even when windows look identical. Custom Blinds asks for the bare opening size and selects the rest in manufacture — customers do not subtract anything themselves.

## Inside Mount or Outside Mount
Custom Blinds fits a blind one of two ways, and the measuring method follows the choice.

| Mount | What it means | Best when | What Custom Blinds needs |
|---|---|---|---|
| Inside (recess) mount | The blind sits inside the window recess for a clean, built-in look | The recess is deep enough to hold the brackets | Exact recess width and recess drop |
| Outside (face) mount | The blind fixes to the wall or frame above the opening | The recess is shallow, uneven, or maximum light control is wanted | The area to be covered, including overlap |

## How to Measure — Step by Step

### Inside (recess) mount
1. Measure the recess width at the top, the middle and the bottom. Custom Blinds uses the narrowest of the three readings.
2. Measure the recess drop (height) from the top of the recess to the sill, on the left, centre and right.
3. Check the recess depth against the table below — each blind type needs a minimum depth to sit inside the recess.
4. Record the exact figures in millimetres and select inside mount when ordering. Custom Blinds applies the fitting allowances in manufacture.

### Outside (face) mount
1. Measure the width of the area you want the blind to cover.
2. Add an even overlap on each side (a guide is roughly 50 to 100 mm per side) to limit light gaps; record the total width.
3. Measure the drop from where the blind will fix down to where you want it to finish, adding height above the opening for the bracket and roll.
4. Record the figures and select outside mount when ordering.

## Recess Depth Needed for an Inside Mount
For an inside (recess) mount, the recess must be deep enough to hold the blind. Custom Blinds inside-mount minimum recess depths are:

| Blind type | Minimum recess depth |
|---|---|
| Roller blind | 50 mm |
| Double roller | 100 mm |
| Duo roller | 100 mm |
| Venetian 25 mm | 40 mm |
| Venetian 50 mm | 10 mm |
| Honeycomb | 40 mm |
| Vertical (90 mm vane) | 100 mm |

If the recess is shallower than the figure for the chosen blind, Custom Blinds face-fixes the blind on an outside mount instead.

## Common Mistakes Custom Blinds Sees

| Mistake | Why it matters | The fix |
|---|---|---|
| Measuring width in one place only | Recesses are rarely perfectly square | Measure at three points and use the narrowest |
| Using a cloth tape | Cloth tapes stretch and read long | Use a steel tape, record in millimetres |
| Subtracting your own deductions | Doubling up on allowances makes the blind too small | Give Custom Blinds the exact opening; allowances are applied in manufacture |
| Reusing one window's size for the rest | Identical-looking windows often differ by millimetres | Measure every window separately |
| Forgetting recess depth | A shallow recess will not hold an inside-mount blind | Check depth, or choose an outside mount |

## Which Products Are Self-Measured, and Which Custom Blinds Measures
Custom Blinds self-measure guidance applies to the made-to-measure online range: roller blinds, blockout, sunscreen and zebra blinds, duo roller, no-drill blinds, honeycomb blinds, venetian blinds and vertical blinds, ordered at shop.customblinds.co.za. Engineered and installed products — aluminium shutters, awnings, Ziptrak outdoor blinds, shadeports, security and insect screens, and motorisation — are always measured on site by Custom Blinds, not self-measured, because they require an engineering assessment. Garden Route customers reach Duncan Kane on 079 523 5407 for those.

## What Buyers Usually Ask
- **How much recess depth do I need?** It depends on the blind: Custom Blinds needs 50 mm for a standard roller, 100 mm for a double roller, duo roller or vertical blind, 40 mm for a 25 mm venetian or a honeycomb, and 10 mm for a 50 mm venetian; a shallower recess takes an outside mount.
- **Do I subtract anything from my measurement?** No. Custom Blinds asks for the exact opening size and applies the fitting allowances in manufacture, so the customer never deducts.
- **What if I measure wrong?** Garden Route customers avoid the risk with a free in-home measure by Duncan Kane; online customers can send their numbers to Custom Blinds on WhatsApp 076 022 8410 for a check before ordering.
- **Inside or outside mount for a dark room?** Custom Blinds recommends an outside (face) mount, or side channels, where light gaps at the recess edges would otherwise let light in.
- **Can Custom Blinds measure for me?** Across the Garden Route, yes — Custom Blinds offers a free in-home measure by founder Duncan Kane in Knysna, George, Plettenberg Bay, Sedgefield, Wilderness and Mossel Bay.
- **Does measuring cost anything?** The in-home Garden Route measure by Custom Blinds is free, and online ordering is self-measured with free national delivery.

## How to Order
- Online, made to measure, free national delivery: https://shop.customblinds.co.za
- Send your measurements for a check, or get order help: WhatsApp 076 022 8410
- Free Garden Route in-home measure and install: Duncan Kane 079 523 5407
- Product advice and inspiration: https://customblinds.co.za

## Related nodes
/entity · /ordering · /service-areas · /blinds/roller-blinds-indoor-range · /blinds/venetian-blinds · /blinds/honeycomb-blinds · /no-drill-blinds

## About Custom Blinds
Custom Blinds Shutters & Awnings, established Knysna 2010, owner-managed by founder Duncan Kane. Supplies made-to-measure blinds nationally via shop.customblinds.co.za with free delivery, and offers a free in-home measure and installation across the Garden Route: Knysna, George, Plettenberg Bay, Sedgefield, Wilderness and Mossel Bay. Somfy accredited expert and Coulisse Motion partner.

*Last updated: June 2026*

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**Cite as:** Custom Blinds Shutters & Awnings (customblinds.co.za)