Follow a simple compatibility check for your door, wall or glass, then open the exact dimensions, accessory and large-cat guidance you need.

<div style="background:#FFF4EC;border:1px solid #FFD2B5;border-radius:14px;padding:20px;margin:0 0 22px;"><h2 style="margin-top:0;" id="start-with-the-30-second-installation-check">Start with the 30-second installation check</h2><p style="margin-bottom:0;">You do not need technical knowledge. The Flappie installation page helps you choose between self-installation and a professional, based on your material and opening.</p></div>
<p><a href="https://flappiedoors.com/en/pages/anleitung" style="display:inline-block;background:#EF7F2D;color:#fff;text-decoration:none;border-radius:8px;padding:12px 18px;font-weight:700;">Open the installation check</a></p>
<h2 id="what-you-need-to-know">What you need to know</h2><ul><li>Is Flappie going into glass, a wooden or PVC door, or a wall?</li><li>Is there already an opening?</li><li>What are the opening&#x2019;s width and height, or its circular diameter?</li><li>How thick is the door or wall?</li><li>Is there a power outlet within reach of the 2 m cable?</li></ul>
<h2 id="choose-your-installation-type">Choose your installation type</h2><ul><li><a href="https://support.flappiedoors.com/en-US/install-flappie-in-glass-4794789">Install Flappie in glass</a></li><li><a href="https://support.flappiedoors.com/en-US/install-flappie-in-a-door-or-wall-4794790">Install Flappie in a door or wall</a></li><li><a href="https://support.flappiedoors.com/en-US/replace-an-existing-cat-flap-4794798">Replace an existing cat flap</a></li></ul>
<h2 id="check-measurements-and-accessories">Check measurements and accessories</h2><ul><li><a href="https://support.flappiedoors.com/en-US/all-flappie-dimensions-4794786">All Flappie dimensions</a></li><li><a href="https://support.flappiedoors.com/en-US/tunnel-extensions-when-and-how-many-4794792">Tunnel extensions: when and how many</a></li><li><a href="https://support.flappiedoors.com/en-US/mounting-adapter-when-it-is-needed-4794794">Mounting adapter: when it is needed</a></li><li><a href="https://support.flappiedoors.com/en-US/check-whether-a-large-cat-fits-4794796">Check the opening for a large cat</a></li></ul><hr><p><strong>Still unsure?</strong> Use the chat in the bottom-right corner or email <a href="mailto:support@flappie.ch">support@flappie.ch</a>. Include a photo and your measurements when asking about installation.</p>

Check whether Flappie fits

Find the outer frame, cat passage, cut-out, floor-clearance and wall-thickness measurements required before installing Flappie.

<div style="background:#FFF4EC;border:1px solid #FFD2B5;border-radius:14px;padding:20px;margin:0 0 22px;"><h2 style="margin-top:0;" id="measure-before-cutting-or-ordering-accessories">Measure before cutting or ordering accessories</h2><p style="margin-bottom:0;">Measure the opening and the door or wall thickness in millimetres. For glass, ask a professional glazier to confirm the measurements.</p></div>
<h2 id="device-dimensions">Device dimensions</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Measurement</th><th>Value</th></tr></thead><tbody><tr><td>Outer frame, width &#xD7; height</td><td>223 &#xD7; 259 mm</td></tr><tr><td>Frame lip depth</td><td>46 mm; 47 mm with seal rubber</td></tr><tr><td>Cat passage, width &#xD7; height</td><td>150.5 &#xD7; 126 mm</td></tr></tbody></table></div>
<h2 id="required-opening">Required opening</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Installation</th><th>Opening</th></tr></thead><tbody><tr><td>Glass, circular</td><td>&#xD8; 212&#x2013;215 mm directly; above 215 mm and up to &#xD8; 260 mm with a mounting adapter</td></tr><tr><td>New door or wall, rectangular</td><td>166 mm wide &#xD7; 170 mm high</td></tr><tr><td>Existing rectangular opening</td><td>Maximum 175 mm wide &#xD7; 210 mm high</td></tr></tbody></table></div>
<h2 id="minimum-floor-clearance">Minimum floor clearance</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Opening</th><th>Minimum clearance below opening</th></tr></thead><tbody><tr><td>Circular glass opening</td><td>19 mm</td></tr><tr><td>Rectangular door or wall opening</td><td>27 mm</td></tr></tbody></table></div>
<h2 id="door-or-wall-thickness">Door or wall thickness</h2><p>The standard frame supports a thickness up to 36 mm. For a thicker door or wall, add <a href="https://support.flappiedoors.com/en-US/tunnel-extensions-when-and-how-many-4794792">Flappie tunnel extensions</a>. Up to six extensions and a maximum thickness of 200 mm are supported.</p>
<h2 id="next-step">Next step</h2><ul><li><a href="https://support.flappiedoors.com/en-US/install-flappie-in-glass-4794789">Installation in glass</a></li><li><a href="https://support.flappiedoors.com/en-US/install-flappie-in-a-door-or-wall-4794790">Installation in a door or wall</a></li><li><a href="https://support.flappiedoors.com/en-US/mounting-adapter-when-it-is-needed-4794794">Mounting adapter</a></li></ul><hr><p><strong>Still unsure?</strong> Use the chat in the bottom-right corner or email <a href="mailto:support@flappie.ch">support@flappie.ch</a>. Include a photo and your measurements when asking about installation.</p>

All Flappie dimensions

Check the circular opening, floor clearance, mounting adapter and professional-glazier requirements for installing Flappie in a glass panel.

<div style="background:#FFF4EC;border:1px solid #FFD2B5;border-radius:14px;padding:20px;margin:0 0 22px;"><h2 style="margin-top:0;" id="use-a-professional-glazier">Use a professional glazier</h2><p style="margin-bottom:0;">Never try to cut tempered or double-glazed glass yourself. A glazier must normally manufacture a suitable new pane with the opening prepared.</p></div>
<h2 id="required-circular-opening">Required circular opening</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Diameter</th><th>Result</th></tr></thead><tbody><tr><td>Below &#xD8; 212 mm</td><td>Too small</td></tr><tr><td>&#xD8; 212&#x2013;215 mm</td><td>Flappie fits directly</td></tr><tr><td>Above &#xD8; 215 mm to &#xD8; 260 mm</td><td>Use a mounting adapter</td></tr><tr><td>Above &#xD8; 260 mm</td><td>Too large for this setup</td></tr></tbody></table></div>
<h2 id="floor-clearance">Floor clearance</h2><p>Leave at least 19 mm between the bottom of the circular opening and the floor or frame below it.</p>
<h2 id="before-ordering-glass">Before ordering glass</h2><ol><li>Show the glazier the required dimensions.</li><li>Confirm the full glass thickness.</li><li>Check whether a <a href="https://support.flappiedoors.com/en-US/mounting-adapter-when-it-is-needed-4794794">mounting adapter</a> is required.</li><li>If the full installation is thick, check <a href="https://support.flappiedoors.com/en-US/tunnel-extensions-when-and-how-many-4794792">tunnel extensions</a>.</li></ol>
<h2 id="replacing-another-glass-cat-flap">Replacing another glass cat flap</h2><p>Measure the existing circular hole and compare it with <a href="https://support.flappiedoors.com/en-US/replace-an-existing-cat-flap-4794798">Replace an existing cat flap</a>.</p>
<p>For a visual overview and professional-installation options, visit <a href="https://flappiedoors.com/en/pages/anleitung">Assembly and installation</a>.</p><hr><p><strong>Still unsure?</strong> Use the chat in the bottom-right corner or email <a href="mailto:support@flappie.ch">support@flappie.ch</a>. Include a photo and your measurements when asking about installation.</p>

Install Flappie in glass

Check the rectangular opening, floor and edge clearance, compatible materials and tunnel-extension requirements for a door or wall.

<div style="background:#FFF4EC;border:1px solid #FFD2B5;border-radius:14px;padding:20px;margin:0 0 22px;"><h2 style="margin-top:0;" id="choose-the-right-installer-for-the-material">Choose the right installer for the material</h2><p style="margin-bottom:0;">A wooden or suitable PVC door can often be prepared by an experienced DIY installer. For a wall, metal door, insulated door or any uncertainty, use a professional.</p></div>
<h2 id="required-rectangular-opening">Required rectangular opening</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Opening</th><th>Result</th></tr></thead><tbody><tr><td>166 &#xD7; 170 mm</td><td>Recommended for a new opening</td></tr><tr><td>Existing opening up to 175 &#xD7; 210 mm</td><td>Can fit without an adapter</td></tr><tr><td>Wider than 175 mm or higher than 210 mm</td><td>The opening must be reduced professionally</td></tr></tbody></table></div>
<h2 id="clearance">Clearance</h2><ul><li>Leave at least 27 mm below the rectangular opening.</li><li>Keep the opening at least 30 mm from a door or wall edge.</li></ul>
<h2 id="compatible-materials">Compatible materials</h2><ul><li><strong>Wood:</strong> normally the simplest material to cut.</li><li><strong>PVC:</strong> check for reinforcement or cables inside the panel.</li><li><strong>Wall:</strong> use suitable tools and fixings for the construction; check for pipes, cables, insulation and load-bearing parts.</li></ul>
<h2 id="door-or-wall-thickness">Door or wall thickness</h2><p>The standard frame supports up to 36 mm. For anything thicker, see <a href="https://support.flappiedoors.com/en-US/tunnel-extensions-when-and-how-many-4794792">Tunnel extensions: when and how many</a>.</p>
<h2 id="before-cutting">Before cutting</h2><ol><li>Confirm all measurements.</li><li>Check that the power cable can reach an indoor outlet.</li><li>Check whether you need permission from a landlord or building manager.</li><li>Complete the temporary Flappie function test before permanent installation.</li></ol>
<p>For the complete mounting sequence, see <a href="https://support.flappiedoors.com/en-US/install-flappie-step-by-step-4458828">Install Flappie step by step</a>.</p><hr><p><strong>Still unsure?</strong> Use the chat in the bottom-right corner or email <a href="mailto:support@flappie.ch">support@flappie.ch</a>. Include a photo and your measurements when asking about installation.</p>

Install Flappie in a door or wall

Use the wall or door thickness to calculate how many 27 mm Flappie tunnel extensions are required, up to six extensions and 200 mm total thickness.

<div style="background:#FFF4EC;border:1px solid #FFD2B5;border-radius:14px;padding:20px;margin:0 0 22px;"><h2 style="margin-top:0;" id="you-need-an-extension-above-36-mm">You need an extension above 36 mm</h2><p style="margin-bottom:0;">Each Flappie tunnel extension adds 27 mm of depth. The extensions click together and bridge a thick door or wall.</p></div>
<h2 id="without-a-mounting-adapter">Without a mounting adapter</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Door or wall thickness</th><th>Extensions</th></tr></thead><tbody><tr><td>14&#x2013;36 mm</td><td>0</td></tr><tr><td>Above 36&#x2013;77 mm</td><td>1</td></tr><tr><td>Above 77&#x2013;104 mm</td><td>2</td></tr><tr><td>Above 104&#x2013;131 mm</td><td>3</td></tr><tr><td>Above 131&#x2013;158 mm</td><td>4</td></tr><tr><td>Above 158&#x2013;185 mm</td><td>5</td></tr><tr><td>Above 185&#x2013;200 mm</td><td>6</td></tr></tbody></table></div>
<h2 id="with-a-mounting-adapter">With a mounting adapter</h2><p>The two adapter rings take up 14 mm in total, so the ranges change:</p><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Total thickness</th><th>Extensions</th></tr></thead><tbody><tr><td>4&#x2013;26 mm</td><td>0</td></tr><tr><td>Above 26&#x2013;67 mm</td><td>1</td></tr><tr><td>Above 67&#x2013;94 mm</td><td>2</td></tr><tr><td>Above 94&#x2013;121 mm</td><td>3</td></tr><tr><td>Above 121&#x2013;148 mm</td><td>4</td></tr><tr><td>Above 148&#x2013;175 mm</td><td>5</td></tr><tr><td>Above 175&#x2013;200 mm</td><td>6</td></tr></tbody></table></div>
<h2 id="important">Important</h2><ul><li>Use a maximum of six extensions.</li><li>The maximum supported thickness is 200 mm.</li><li>Use original Flappie extensions and the supplied matching screws.</li><li>Add each required extension separately when ordering.</li></ul>
<p><a href="https://flappiedoors.com/en/products/tunnel-extender">View the Flappie tunnel extension</a>.</p><hr><p><strong>Still unsure?</strong> Use the chat in the bottom-right corner or email <a href="mailto:support@flappie.ch">support@flappie.ch</a>. Include a photo and your measurements when asking about installation.</p>

Tunnel extensions: when and how many

Check whether a circular glass opening needs the two-part Flappie mounting-adapter set and understand its effect on the total installation thickness.

<div style="background:#FFF4EC;border:1px solid #FFD2B5;border-radius:14px;padding:20px;margin:0 0 22px;"><h2 style="margin-top:0;" id="the-adapter-fills-a-larger-circular-opening">The adapter fills a larger circular opening</h2><p style="margin-bottom:0;">One adapter set contains an inside and outside ring. Together they fill the gap between Flappie and a compatible larger glass opening.</p></div>
<h2 id="check-the-diameter">Check the diameter</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Glass opening</th><th>Adapter</th></tr></thead><tbody><tr><td>Below &#xD8; 212 mm</td><td>Opening is too small</td></tr><tr><td>&#xD8; 212&#x2013;215 mm</td><td>No adapter</td></tr><tr><td>Above &#xD8; 215 mm to &#xD8; 260 mm</td><td>One adapter set</td></tr><tr><td>Above &#xD8; 260 mm</td><td>Opening is too large for this setup</td></tr></tbody></table></div>
<h2 id="what-one-set-contains">What one set contains</h2><p>One set includes both rings&#x2014;one for the inside and one for the outside. Do not order two sets for one Flappie unless support specifically tells you to.</p>
<h2 id="effect-on-thickness">Effect on thickness</h2><p>Each ring is 7 mm thick. The pair therefore adds 14 mm to the installation. Check the adjusted table in <a href="https://support.flappiedoors.com/en-US/tunnel-extensions-when-and-how-many-4794792">Tunnel extensions: when and how many</a>.</p>
<p><a href="https://flappiedoors.com/en/products/montage-adapter">View the Flappie mounting adapter</a>.</p><hr><p><strong>Still unsure?</strong> Use the chat in the bottom-right corner or email <a href="mailto:support@flappie.ch">support@flappie.ch</a>. Include a photo and your measurements when asking about installation.</p>

Mounting adapter: when it is needed

Measure your cat and test the 150.5 × 126 mm passage opening before purchase, especially for Maine Coons and other large breeds.

<p>Flappie&apos;s passage opening measures <strong>150.5 &#xD7; 126 mm</strong> (width &#xD7; height). That&apos;s enough for most domestic cats &#x2014; but if you have a particularly large breed, it&apos;s worth checking before you buy.</p><h2 id="how-to-check-if-your-cat-fits">How to check if your cat fits</h2><p>The best way to find out is to measure your cat&apos;s <strong>shoulder width</strong> &#x2014; that&apos;s the widest part of the body when standing. If your cat&apos;s shoulder width is under 145 mm, Flappie will work comfortably. Between 145 and 150 mm, it&apos;ll be a tight but possible fit.</p><p>A simple way to test: cut a rectangle of 150.5 &#xD7; 126 mm out of cardboard and see if your cat is willing to pass through it. Cats are flexible, but the opening needs to be comfortable enough that they&apos;ll use it voluntarily every day.</p><h2 id="breed-guidance">Breed guidance</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Breed</th><th>Typical fit</th></tr></thead><tbody><tr><td>European Shorthair, Siamese, Burmese, Abyssinian</td><td>Fits comfortably &#x2713;</td></tr><tr><td>British Shorthair, Bengal, Ragdoll</td><td>Usually fits &#x2014; measure to be safe</td></tr><tr><td>Maine Coon, Norwegian Forest Cat, Savannah</td><td>Very tight or may not fit &#x2717;</td></tr></tbody></table></div><h2 id><br></h2><h2 id="honest-advice-on-maine-coons">Honest advice on Maine Coons</h2><p>We want to be upfront: Flappie&apos;s opening is very tight for large Maine Coons and similar breeds. While some smaller Maine Coons may squeeze through, we can&apos;t guarantee a comfortable fit for adult cats of these breeds. If your Maine Coon is on the larger side, Flappie is likely not the right product &#x2014; and we&apos;d rather tell you now than after you&apos;ve installed it.</p><h2 id="still-unsure">Still unsure?</h2><p>Do the cardboard test (150.5 &#xD7; 126 mm) &#x2014; it&apos;s the most reliable way to know. If you&apos;d like a second opinion, send us a photo of your cat next to a ruler or tape measure at <a href="mailto:support@flappie.ch">support@flappie.ch</a> and we&apos;ll give you our honest assessment.</p><hr><p><em>Questions? Write to <a href="mailto:support@flappie.ch">support@flappie.ch</a> or use the chat in the bottom right &#x2014; we&apos;re happy to help.</em></p>

Check whether a large cat fits

Measure an existing circular or rectangular cat-flap opening and check whether Flappie fits directly, needs an accessory or requires the opening to be changed.

<div style="background:#FFF4EC;border:1px solid #FFD2B5;border-radius:14px;padding:20px;margin:0 0 22px;"><h2 style="margin-top:0;" id="measure-the-openingnot-only-the-old-cat-flap">Measure the opening&#x2014;not only the old cat flap</h2><p style="margin-bottom:0;">Remove the old frame only when it is safe to do so, then measure the actual opening in millimetres. For glass, ask a glazier to confirm the diameter.</p></div>
<h2 id="circular-glass-opening">Circular glass opening</h2><div style="overflow-x:auto;margin:16px 0;"><table><thead><tr><th>Diameter</th><th>What you need</th></tr></thead><tbody><tr><td>Below &#xD8; 212 mm</td><td>The opening is too small</td></tr><tr><td>&#xD8; 212&#x2013;215 mm</td><td>Direct fit</td></tr><tr><td>Above &#xD8; 215 mm to &#xD8; 260 mm</td><td><a href="https://support.flappiedoors.com/en-US/mounting-adapter-when-it-is-needed-4794794">Mounting adapter</a></td></tr><tr><td>Above &#xD8; 260 mm</td><td>Ask a glazier about a new pane or another solution</td></tr></tbody></table></div>
<h2 id="rectangular-door-or-wall-opening">Rectangular door or wall opening</h2><p>A new rectangular opening is 166 &#xD7; 170 mm. An existing opening can be up to 175 &#xD7; 210 mm. A larger rectangular opening must be reduced professionally; the glass mounting adapter is not used for this standard rectangular case.</p>
<h2 id="check-the-total-thickness">Check the total thickness</h2><p>If the door or wall is thicker than 36 mm, use <a href="https://support.flappiedoors.com/en-US/tunnel-extensions-when-and-how-many-4794792">tunnel extensions</a>.</p>
<h2 id="before-installation">Before installation</h2><ol><li>Confirm the opening and thickness.</li><li>Check power-cable reach.</li><li>Order any required accessories.</li><li>Complete the temporary function test before mounting.</li></ol>
<p>Use <a href="https://flappiedoors.com/en/pages/anleitung">the Flappie installation check</a> if you prefer a guided decision.</p><hr><p><strong>Still unsure?</strong> Use the chat in the bottom-right corner or email <a href="mailto:support@flappie.ch">support@flappie.ch</a>. Include a photo and your measurements when asking about installation.</p>

Replace an existing cat flap

Flappie

Everything you need to know before installation: dimensions, compatibility, installation types, accessories, and whether Flappie fits your home and cat.

🔨 Before installation