Remington CroftBlackout Curtain Measuring for Full Light Coverage
Last updated: September 16, 2026 — rechecked against Dunelm and M&S measuring guides plus Jane Clayton hardware specs and updated where details changed.
Reviewed by Emily Holmes, General Reviewer, following our test method.
A practical walkthrough for how to measure for blackout curtains: blackout overlap width, side light gaps, top light leak in plain order, the main options compared side by side, and the mistakes that cause redos flagged up front. Pick one option from the table and work it fully.
Quick answer: compare paths first using the table below. Confirm fit against blackout overlap width, side light gaps, top light leak, wraparound rod seal. Check the mistakes section before you commit. Details and FAQs below.
Quick Comparison Table Standard vs Blackout Overlap Needs
Pick one path first — that choice matters more than any single tip below. The table maps the main options; the sections below resolve fit and failure modes.
Illustrative stock photo via Pexels.
| Method | Key Points | Best For |
|---|---|---|
| Quick Comparison Table Standard vs Blackout Overlap Needs | Main checks for quick comparison table standard vs blackout overlap needs — full detail in the section below | See whether this matches your case below |
| How Much Extra Width Blocks Side Light | Main checks for how much extra width blocks side light — full detail in the section below | See whether this matches your case below |
| Height Tricks to Stop Top Glow | Main checks for height tricks to stop top glow — full detail in the section below | See whether this matches your case below |
Related: How to Measure for Curtains in 2026 (Width, Drop, Fullness).
Heads-up: blackout overlap width, side light gaps, top light leak, wraparound rod seal differ from case to case, so use the steps here as the reliable core and confirm current specifics in Sources before you decide.
How Much Extra Width Blocks Side Light
Work through blackout overlap width, side light gaps, top light leak in order: confirm the starting point, run the steps once without skipping, then verify the result before moving on.
- Use it when: your case matches this option.
- Skip it when: another option below fits better.
- Spec to confirm: the one detail readers get wrong here — check it in Sources.
Height Tricks to Stop Top Glow
For height tricks to stop top glow, define the goal, try the smallest complete version first, and check it against blackout overlap width, side light gaps, top light leak before continuing. Where details vary, verify specifics in Sources.
Illustrative stock photo via Pexels.
Layering With Shades for Nurseries
For layering with shades for nurseries, define the goal, try the smallest complete version first, and check it against blackout overlap width, side light gaps, top light leak before continuing. Where details vary, verify specifics in Sources.
Wraparound Rod Light Seal Data
Measure the hardware, not the window — that's the whole game. Width multiplies by header: pencil pleat wants about one pole-width per panel (two for the pair), eyelet about double, tab tops around one-and-a-half — window width alone always undershoots (Dunelm, M&S guides). Drop starts somewhere different on every heading: track top, pole top, ring eye, eyelet top plus three centimetres, tab top — measure from your hardware's origin or you'll finish an inch or two short (Jane Clayton specs).
Setup Tips to Get Better Results Faster
Prep beats rework here: gather what you need once, note your starting point, keep blackout overlap width, side light gaps, top light leak in mind while you work, and stop at the first unexpected result to re-check fit.
FAQs Blackout Coverage
What is the fastest way to handle this?
Start with the comparison table, pick one path, and finish its checks fully. Switching mid-way is slower than one clean pass.
What do most guides miss here?
Most short guides skip the fit checks — blackout overlap width, side light gaps, top light leak. The sections above cover them so you don't have to piece it together from five tabs.
When should I choose a different option here?
When your situation points to another option below — use the related guide for that option instead of forcing this one to fit.
Where can I verify current details?
Use the primary sources in Sources below — provider pages and official references change faster than any guide.
How much wider than the window should curtains be?
Roughly double the pole width for eyelets, less for pencil pleats — the header sets the multiplier, not the glass.
Bottom Line
Compare the options first, confirm fit against blackout overlap width, side light gaps, top light leak, then check the mistakes section. Use the related guides below for background and nearby options.
Related Guides
- How to Measure for Curtains in 2026 (Width, Drop, Fullness)
- How to Measure Curtain Width and Fullness Ratio
- Inside vs Outside Mount Curtain Measuring Compared
- Curtain Rod Size Chart and Length Picker Guide
Sources: verify current details in primary references for how to measure for blackout curtains — Sleep foundation darkening guides + retailer blackout charts + parent forums. Evidence is thin where providers differ; prefer official pages over aggregators.