Wood frames & “wood-outs.”

Find the original frame

Start with the construction you can actually see. Older double-hung windows may have weights and pulleys, spring balances, jamb liners, parting stops, interior stops and exterior blind stops. A previous replacement can hide the original wood frame behind another frame and metal capping.

“Wood-out” identifies a trade category, not a complete measuring instruction. Write down whether the scope retains the old wood jambs, head and sill or removes them. A window from the same nominal family can need a different new size when the removal boundary changes.

Inspect accessible wood for deterioration, loose joints, previous repairs and attachment. If the retained sill or frame needs reconstruction, the measurement must account for the planned repair rather than a damaged edge that will disappear.

Measure the retained pocket

For a wood-frame insert application, use the contact surfaces illustrated by the chosen product’s measuring guide. Typical wood-pocket guides distinguish the wood frame surfaces from stops, liners, pulleys and weatherstrip. Do not include removable obstructions in one reading and exclude them in another.

1. Establish the head and both side-jamb reference faces.
2. Record widths at top, middle and bottom at the same depth.
3. Locate the specified sill contact before recording left, center and right heights.
4. Measure the available pocket depth and any stop or hardware projections.
5. Check diagonals, plumb, level, bow and accessible attachment material.

If a liner or sash hides the reference, use an authorized access procedure. Do not force a sash, remove loaded balance components without a service procedure, or guess the thickness behind the obstruction.

The stool is not the sill

A sloping sill produces different heights at different front-to-back positions. Match the guide’s specified contact point, and record the sill angle when required. The stool, sill stop, existing sill and proposed support surface are distinct references.

Some product families offer particular sill bevels; others require a minimum existing slope or specific support. Marvin’s Elevate instructions, for example, discuss its own 8-degree bevel and pocket conditions. Those details explain why “all inserts fit a standard pocket” is not an adequate order rule.

When the true sill is hidden by a picture sash or previous insert, plan access and document the uncertainty. Do not add another window’s stool thickness to a hidden height and release the order as verified.

Separate a sash kit from an insert

A replacement sash or conversion kit must match a specific existing product. It may be selected using product identification and visible glass dimensions, as in Andersen’s Narroline conversion-kit guide. That does not make visible glass a valid ordering reference for an unrelated complete window.

Record brand, series, labels, configuration, sash dimensions requested by the supplier and photographs of the existing profile. Confirm that the frame is eligible for the kit. A kit is not a generic way to avoid measuring the opening.

Release checklist for a wood opening

• Every retained and removed layer is named.
• The true width and height contacts are visible or otherwise reliably established.
• Sill angle, depth and stop projections match the proposed series.
• Repair, support and water-management scope are resolved.
• The supplier’s entry mode is identified; any automatic deduction is documented.
• Similar-looking openings have individual measurements and IDs.