How to Measure Your Fence Post (and Choose the Right Post Top Size)
Choosing the right post top starts with one simple but important step: accurately measuring your fence post. Whether you’re building a new fence or upgrading an existing one, correct measurements ensure a perfect fit—no gaps, no wobbling, and no sizing surprises on installation day.
At Ledro House, all our post tops are designed for a snug, secure fit, whether they sit directly on top of the post or fit over it. This guide explains how to measure your post properly and match it to the correct size post top—especially important for post tops with internal dimensions designed to slide over your post.
Why Accurate Measuring Matters
Fence posts rarely measure exactly what their label says. For example, a 90mm timber post may measure anywhere from 88mm to 92mm depending on moisture, age, and manufacturer. Metal posts can vary slightly too.
Accurate measuring ensures:
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Your post top fits securely
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Your chosen design sits correctly
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Installation is fast and frustration-free
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You achieve a professional, finished appearance
This step is essential for Ledro House’s carefully crafted post tops.
Step 1: Identify Your Post Type
Before measuring, determine what kind of post you have:
Timber post
Measure edge to edge. Variations are normal, especially on older or painted posts.
Steel or aluminium post
Measure the outside dimensions.
Custom, older, or non-standard posts
These may require a custom-sized post top.
Step 2: Use Accurate Tools
For best results use:
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A tape measure
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A ruler or calipers (for the highest accuracy)
Measure to the nearest millimetre.
Step 3: Measure the Width of Your Post
For post tops that FIT OVER the post: Internal size = your post size + 2mm
Ledro House post tops that slide over the post are manufactured with an internal dimension 2mm larger than the nominal post size.
This ensures the post top slides on easily while remaining snug once installed—without being too tight or too loose.
Example
If you are buying a 90mm post top, the internal measurement of the post top will be 92mm.
It is specifically designed to fit over a 90mm post.
This sizing rule applies across our over-post designs:
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70mm post → 72mm internal
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90mm post → 92mm internal
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100mm post → 102mm internal
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125mm post → 127mm internal
Always select the post top based on your post measurement, not the internal measurement.
For post tops that SIT ON TOP of the post
If the design sits on the top surface, you only need the exact width of the post.
Example:
A 100mm post requires a 100mm post top designed to sit on top.
Step 4: Check the Size Table on ledrohouse.com
Every post top on ledrohouse.com includes a simple sizing table showing:
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Whether the design fits over the post or on top
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The matching post size (e.g., 90mm post)
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The internal measurement for over-post designs (post size + 2mm)
This removes the guesswork and ensures you select the correct size.
If you're unsure, just email us at [email protected] and we’ll confirm it for you.
Step 5: If Your Post Isn’t Standard, Custom Sizes Are Available
Many older fences or custom-built fences have non-standard post sizes. To accommodate this, Ledro House offers custom fit options so your post tops sit perfectly—no wobble, no gaps.
Simply send us your precise measurement and we’ll take care of the rest.
Tips for Accurate Measuring
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Measure both directions (e.g., left–right and front–back).
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If your post varies slightly, use the largest measurement.
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Avoid measuring over thick paint—measure the actual timber or metal where possible.
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Double-check before ordering.
Choose the Perfect Fit at Ledro House
With accurate measurements and a clear understanding of how our sizing works—especially the +2mm internal allowance for post tops that fit over the post—you’ll be able to select the perfect product with confidence.
Browse Australia’s largest range of post tops at ledrohouse.com, or reach out to us at [email protected] for personalised sizing help or custom orders.
Your fence deserves a perfect finish—and it starts with choosing the right size post top.