Custom-Sized Koch Multi-Pleat XL8 Air Filter – MERV 8 Efficiency

Description

This is our custom-size Koch Multi-Pleat XL8 air filter, delivering MERV 8 filtration built to your exact dimensions. When your HVAC system has a non-standard filter opening — common in older homes, commercial rooftop units, and legacy air handlers — stock nominal sizes leave gaps that let unfiltered air bypass the filter. Custom sizing closes that gap so your system actually filters the air it handles.

When a custom size is the right call

• Legacy air handlers with non-standard filter openings
• Commercial rooftop units with manufacturer-specific filter slots
• Older residential returns that don’t match today’s nominal sizes
• Replacement for a filter you’ve been trimming or stacking to fit
• Built-in filter housings where the equipment was designed around the filter

How to order

Measure your existing filter (not the housing it sits in — filters are typically slightly smaller than the housing for installation clearance) to the nearest 1/8 inch in length, width, and depth. If you’re unsure about measurements or which filter spec is right for your system, contact us with a photo of your existing filter or housing and we’ll confirm before production. Our Filter Fit Guarantee means if you measure wrong, we’ll remake the filter at no additional cost.

MERV 8 — standard efficiency

MERV 8 is the baseline for good residential and light commercial filtration: effective against household dust, lint, larger pollens, and dust-mite debris — with low pressure drop so it protects airflow and coil performance. It’s the right choice when system protection and clean returns are the goal, not allergen-level filtration.

Construction

• Media: 100% synthetic blended fibers, engineered for high initial efficiency and low pressure drop. Mechanical capture — performance doesn’t fade.
• Frame: Recyclable beverage-board frame with double-wall construction for high-humidity durability. Expanded galvanized-steel grid bonded to the air-exiting side maintains pleat uniformity.
• Max operating temperature: 200°F (93°C) continuous
• Sizing tolerance: Built to 1/8 inch increments

Typical applications

Commercial office buildings, schools, retail, light industrial, and residential HVAC where extended-surface pleated filtration is specified. UL 900 and ULC-S111-07 certified.

Also worth considering

Shopping on price? Our house brand PrimeShield Essential (MERV 8) covers the same efficiency tier across common residential and commercial sizes and is usually the better value. Choose this branded option when your equipment spec sheet or facilities team calls for it specifically.

Questions on fit, quantity, or a commercial quote?

Need a size that isn’t listed, a different pack count, or a quote for a commercial order? Get in touch — we handle facilities and commercial orders daily and can usually match or beat distributor pricing.

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