Questions covered in this guide
Tell the supplier where the windows will go
Include the property location and known installation elevation in the inquiry, alongside the opening list. If the elevation is uncertain, ask how the supplier wants it confirmed. Do not assume that a window stocked for one market is automatically suitable for another. Keep the destination details on the order rather than relying on a casual conversation.
Request the applicable manufacturer guidance
Marvin’s altitude supplement links glass conditions to its product guidelines. It identifies size, shape and configuration as relevant factors. Ask the dealer for the current requirements applying to your chosen product and location. Have the dealer explain any special order or glazing selection and identify the relevant warranty document. Avoid applying a single altitude threshold or generic tube instruction to every brand and glass unit.
Review the complete delivery plan
Use rows for opening, product series, size, glass package, installation elevation and supplier confirmation. Ask whether the planned transport route needs to be considered under the manufacturer’s guidance. Identify who confirms that the delivered product matches the elevation-specific order. If a substitution is proposed, require the same review before accepting it. Keep any handling or installation steps with the qualified supplier and installer; this worksheet is not a procedure for altering a sealed glass unit.
Price the approved configuration
Request an installed total for the confirmed specification and ask which delivery or handling items are included. Save the dealer’s written response with the order and final product identifiers. Use that supplied price for your project budget rather than assuming a national reference covers the special configuration. If suitability remains unresolved, leave the order pending clarification instead of treating the absence of a surcharge as evidence that no special requirement exists.
Sources and supported claims
Marvin’s altitude supplement links glass conditions to its product guidelines.
Source ↗ · national · Checked 2026-10-12
It identifies size, shape and configuration as relevant factors.
Source ↗ · national · Checked 2026-10-12
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