Landmarks commission approves composite tile and copper gutters for 406 Windsor Drive with caveats

The City of Waukesha Landmarks Commission on July 9 approved a Certificate of Appropriateness (COA) for a composite tile roof and copper gutters at 406 Windsor Drive, a Colonial Revival house built in 1938, but added a formal caveat requiring the owner to notify the commission if the chosen materials change.

Commissioners spent the meeting’s longest period on the item, discussing material appearance, longevity, installation risk and potential impacts on state historic tax credits. John Rosenberg, the homeowner and applicant, described multiple contractor estimates ranging from about $42,000 to $90,000 for various replacement options and said he had recently received a written review that raised durability concerns about the proposed polymer/composite tile product.

Rosenberg said the contractor estimates varied depending on the approach; he told the commission about a recent Technical Review: "the polymer shingles were already beginning to warp and fade," he recounted from a reviewer’s field observation. Commissioners noted there is no local stock of matching clay tile and that replacement with an exact historic material would be costly and often infeasible.

Carmen Dela Paz, chair, explained the commission’s position that while historic materials are preferred, the body has in some cases allowed modern alternatives when necessary. A majority of commissioners said the proposed composite tile approximated the house’s appearance from the street and that the applicant had shown good-faith effort to find alternatives. Commissioners and staff urged the owner to buy spare tiles for future repairs and emphasized careful installation.

The commission’s motion approved the Bravo composite tile in a Tuscan clay color, copper case-style gutters and new copper chimney flashing and trim as presented. Approval included a specific direction that the owner must return to the commission if the material choice changes; staff and commissioners also recorded that choosing the composite product could jeopardize eligibility for Wisconsin state historic-preservation tax credits.

Commission discussion cited multiple contractors and options the homeowner reviewed (Renaissance Roofing, Bulldog, and others), the owner’s preferred contractor Bulldog (local), and industry alternatives such as DaVinci and other composite slate/ tile products. Commissioners recorded that warranty claims and long-term product performance are the owner’s responsibility; the commission recommended the owner obtain multiple written estimates and clarified the installation risks associated with using a newer composite product on a large roof.

The motion passed on a voice vote by the commissioners present. Staff will record the COA and the condition that the owner notify the commission if materials change. The owner said he would return with revised materials if needed and would proceed cautiously given the recent reviewer comments about polymer tile durability.