What LPC Actually Wants in a Brooklyn Brownstone Window Application

Brooklyn has more than 30 LPC-designated historic districts plus several hundred individual landmark sites. If you own a brownstone in Brooklyn Heights, Park Slope, Cobble Hill, Carroll Gardens, Fort Greene, DUMBO, Boerum Hill, or any of the other designated areas, replacing your windows almost certainly requires a Landmarks Preservation Commission permit.

What follows is the working knowledge a contractor brings into a Commission application — what reviewers actually look at, what kills an application, and what timeline a homeowner should plan for.

The "In-Kind Replacement" Standard

LPC’s primary test for a replacement window is whether it is "in-kind" — meaning the replacement matches the visual character of what's there. Three things drive that judgment:

• Profile and proportion. The width of the muntins (the bars that divide the panes), the depth and shadow line of the meeting rail, the proportion of glass to frame.
• Material. If the originals were wood, the replacements need to look like wood at the exterior. That usually means painted wood, wood-clad aluminum, or fiberglass with a wood-grain exterior. All-vinyl windows are almost never approved on a brownstone.
• Operation. If the originals were double-hung sash windows, the replacements should be too. Casements or sliders replacing double-hungs trigger an immediate rejection in most districts.

Materials That Get Approved (and Don't)

What reviewers will accept varies by district. Brooklyn Heights generally requires painted wood or wood-clad aluminum with thin sightlines. Park Slope is more flexible — fiberglass and high-quality aluminum with a wood-grain finish are routinely approved. The cast-iron districts in Manhattan (SoHo, Tribeca) require steel for the historic cast-iron buildings themselves.

The product lines we most often specify for designated brownstones:

• Marvin Signature wood-clad — the most-approved workhorse
• Kolbe Heritage Series — when reviewers want a true painted-wood exterior
• Andersen A-Series — for higher-budget all-wood projects
• Pella Architect Series — flexible profile options

The Application Package

A complete LPC permit application for a brownstone window replacement typically includes:

• Existing-condition photographs (each elevation, each opening, with scale reference)
• Dimensioned drawings of every opening
• Manufacturer product cut sheets and section details
• Site plan and elevation drawings showing all proposed changes
• A narrative description explaining how the proposal is in-kind
• Permit application form and filing fee

For multi-window projects in a historic district, a Certificate of No Effect (CNE) is the usual approval. For full-replacement projects involving any visible exterior change, a Permit for Minor Work (PMW) or a full Certificate of Appropriateness (C of A) may be required depending on scope.

Timeline Expectations

LPC review timelines depend on the application type:

• Certificate of No Effect (CNE): typically 4–6 weeks from a complete submission
• Permit for Minor Work (PMW): 6–10 weeks
• Certificate of Appropriateness (C of A): 12–20 weeks (requires a public hearing)

Add another 2–4 weeks for any incomplete-submission cycle. For a typical brownstone replacement that is in-kind and well-documented, plan on 8 weeks from filing to permit in hand.

The Three Reasons Applications Get Rejected

1. Wrong material. Proposing all-vinyl or solid-aluminum windows on a designated brownstone is almost always denied.
2. Wrong proportions. Wider muntins, different meeting-rail depth, larger frames eating into the glass area. The replacement needs to read as the original from the sidewalk.
3. Missing exterior detail. If the original had a specific muntin pattern (true-divided lights vs. simulated-divided), a sash horn, or a particular paint finish, the replacement needs to match.

What Kenemax Brings to a Brownstone Application

We’ve filed more than 150 LPC permits across NYC since 2010. For a Brooklyn brownstone window replacement, our scope typically includes:

• Site survey and existing-conditions documentation
• Product specification matched to your district’s typical requirements
• Full application package preparation, including shop drawings
• Filing and follow-through with the LPC examiner
• Response to any RFI cycles before approval
• Coordination with DOB for the building permit once LPC is approved

The homeowner provides the address, signs the application, and pays the filing fee. We handle the rest.