Baltimore window permit rules — the basics
Like-for-like insert replacement at the same rough opening: no DHCD permit needed. New openings or enlargements: DHCD permit required for structural framing work. The same framework as every other city in this series. What makes Baltimore distinctive is the breadth and rigor of CHAP's historic district review for windows in designated neighborhoods.
CHAP's approach to Baltimore window replacement in historic districts is among the most detailed in this series. The Commission's design guidelines — available at baltimorecity.gov/chap — specify acceptable window materials, divided light configurations, frame profiles, and colors for each of the city's historic districts, which often reflect the architectural character of the specific period when the neighborhood was built. Federal Hill's late-19th century rowhouses have characteristic 2-over-2 double-hung windows; Bolton Hill's earlier Victorian stock often retains 6-over-6 configurations. Replacing these with modern 1-over-1 single-lite vinyl windows — even insert replacements at the same rough opening — is not approvable in CHAP historic districts.
The window types that CHAP approves for Baltimore historic rowhouses vary by district and building era, but consistently favor wood or aluminum-clad wood with true divided lights replicating the historic configuration, fiberglass with flush-glazed divided light profiles, or in some cases high-quality vinyl with simulated divided lights that convincingly replicate the historic sash configuration and profile depth. Snap-in grilles applied to the interior of a flat sash are not acceptable in CHAP historic districts — the divided light must be expressed in the window's actual profile, not simulated with applied grilles. Pre-application consultation with CHAP staff at (410) 396-4866 before selecting window products for any Baltimore historic district property is essential.
Maryland's IECC for Climate Zone 4A requires replacement windows to meet U-factor ≤ 0.35. This applies to both permitted new openings and, when CHAP Certificate of Approval is required, to the replacement products being reviewed. Wood and aluminum-clad wood windows from major manufacturers (Andersen, Marvin, Pella, Lincoln) can meet U-factor ≤ 0.35 while also meeting CHAP's historic character requirements for divided light configurations and frame profiles. Confirm the specific product's U-factor from the NFRC label before purchase. Lead paint EPA RRP certification applies to virtually all of Baltimore's pre-war housing stock — confirm RRP certification for any Baltimore window contractor before signing.
Three Baltimore window replacement scenarios
| Variable | How it affects your Baltimore window project |
|---|---|
| No DHCD permit for insert replacement | Like-for-like insert replacement at same rough opening: no permit. New or enlarged openings in masonry rowhouse walls require DHCD permit plus engineering — more complex than wood-frame. CHAP review still applies for appearance changes in historic districts regardless of permit status. |
| CHAP — extensive Baltimore coverage | Fells Point, Federal Hill, Bolton Hill, Roland Park, Mount Vernon, and many more require CHAP Certificate of Approval for window replacements that alter appearance (material, divided light, profile, color). Even permit-exempt insert replacements trigger CHAP review in designated districts when they change the window's character. Call CHAP (410) 396-4866 before selecting products. |
| Divided light authenticity — CHAP standard | CHAP requires true divided lights (separate glass lites in individual frames), not snap-in interior grilles applied to flat sash. Wood or aluminum-clad wood with true divided lights, or fiberglass with flush-glazed simulated divided lights of appropriate profile depth, are approvable. Flat sash with adhesive grille strips are not acceptable in CHAP historic districts. |
| Masonry window openings — engineering required | Creating new window openings or enlarging existing ones in Baltimore's brick rowhouse walls requires a licensed Maryland structural engineer's lintel specification and masonry cutting plan. More complex and more expensive than equivalent work in wood-frame construction. Budget $800–$1,800 for engineering plus $1,000–$2,500 for masonry work. |
| Maryland IECC U-factor ≤ 0.35 | Climate Zone 4A standard. Less demanding than Boston/Detroit (≤ 0.30) but meaningful for Baltimore's 4,654 HDD winters. Standard double-pane low-E vinyl and wood/aluminum-clad products from major manufacturers easily meet ≤ 0.35. Confirm NFRC label before purchasing for any CHAP-required submission. |
| Lead paint EPA RRP — virtually universal in Baltimore | Baltimore's pre-war rowhouse stock (most of the city) has lead-painted windows. EPA RRP certification required for contractors. Pre-1978 construction means virtually every original Baltimore rowhouse triggers RRP requirements. Verify before signing any Baltimore window contract. |
Baltimore's rowhouse window character — why CHAP reviews matter
Baltimore's historic rowhouse neighborhoods survive because their building fabric has maintained continuity across 150 years. The windows are among the most visible and character-defining elements of that fabric. Federal Hill's uniform streetscapes of late-19th century brick rowhouses with their 2-over-2 double-hung windows create a visual coherence that would be disrupted by sporadic vinyl window replacements with flat sash and snap-in grilles. CHAP's review of window replacements is not bureaucratic interference — it's the mechanism that maintains the visual integrity of neighborhoods that Baltimore's property values, tourism, and quality of life depend on.
For Baltimore homeowners in historic districts, the CHAP process is most effective when approached proactively. The CHAP staff are knowledgeable, approachable, and invested in helping homeowners find workable solutions that meet both their performance needs and the historic district's character standards. A 15-minute pre-application call with CHAP staff to describe the specific building, existing window configuration, and proposed replacement products provides guidance that saves far more time than proceeding without consultation and discovering a product is not approvable after it's already been ordered.
What window replacement costs in Baltimore, MD
Standard vinyl insert replacement: $400–$650/window installed. Aluminum-clad wood (CHAP-compatible): $900–$1,700/window. Fiberglass with flush-glazed divided lights: $700–$1,200/window. New masonry opening (engineering plus masonry plus window): $4,500–$8,500. Lead paint preparation (RRP): $45–$100/window location. CHAP Certificate of Approval fee: $75–$175. DHCD permit for new masonry opening: $100–$175. Baltimore window costs are above Memphis and Louisville, competitive with Portland.
Phone: (410) 396-3000 | baltimorecity.gov/permits CHAP (Commission for Historical and Architectural Preservation) Phone: (410) 396-4866 | baltimorecity.gov/chap
MD HIC: dllr.state.md.us
Common questions about Baltimore window replacement permits
Do I need a permit to replace windows in my Baltimore rowhouse?
Not for insert replacement at the same rough opening. New openings in masonry walls require a DHCD permit plus engineering. For CHAP-designated historic district properties — which covers much of Baltimore's older neighborhoods — a CHAP Certificate of Approval is required for window replacements that alter appearance, even for permit-exempt insert replacements. Call DHCD at (410) 396-3000 to confirm permit requirements and CHAP at (410) 396-4866 to confirm historic district designation for your address before selecting window products.
What window types does CHAP approve for Baltimore historic rowhouses?
CHAP approves window products that replicate the historic window's divided light configuration, frame profile, and visual character. Wood double-hung with true divided lights is the most historically authentic choice. Aluminum-clad wood provides wood's dimensional stability with a moisture-resistant exterior — common in CHAP-approved Federal Hill and Bolton Hill projects. High-quality fiberglass with flush-glazed divided lights of appropriate profile depth is approvable in most Baltimore historic districts. Vinyl with snap-in interior grilles — which produce flat sash with applied grid patterns rather than true divided lights — is generally not approvable in CHAP historic districts. Confirm with CHAP staff before ordering.
How long does CHAP window review take in Baltimore?
Staff-level review (for straightforward replacements in clearly compatible products): 1–2 weeks. Full board review (for products or configurations requiring more evaluation): 3–5 weeks. Staff at (410) 396-4866 can advise which track applies to your proposed project. Most window replacements with historically appropriate products go through staff review. Submitting the NFRC performance data, product literature, and photos of the existing windows along with your application speeds the review process.
General guidance based on publicly available sources as of April 2026. CHAP historic district boundaries and guidelines may be updated. Verify current requirements with DHCD at (410) 396-3000 and CHAP designation at baltimorecity.gov/chap before starting. For a personalized report, use our permit research tool.