WINDOW REPLACEMENT Prperty wners and develpers undertaking rehabilitatin prjects fr bth Tax Act Certificatin and Sectin 106 Cmpliance are encuraged t repair and retain existing histric windws. Hwever, in sme cases, the windws may have deterirated and may need t be replaced. In rder t shw a need fr ttal windw replacement, the cnditin f the existing windws must be dcumented and their replacements must cnfrm t the Secretary f Interir's Standards fr Rehabilitatin. Survey Befre windws can be replaced in a rehabilitatin prject, the existing cnditin f each windw shuld be dcumented. This shuld be undertaken in the frm f a windw survey. The survey is intended t identify the extent f deteriratin in each windw and t prvide a decisin base as t whether the windws shuld be repaired r replaced. It is recmmended that the survey be cnducted and cmpleted by smene wh is knwledgeable in the field f architectural cnservatin r building cnservatin. In rder t cmplete a windw survey the fllwing infrmatin is needed: Drawings Clear, clr, detailed, phtgraphs r representative windws (all majr windw types, all elevatins, and windws in varying cnditins f deteriratin), numbered t cincide with the elevatin drawings. Including the fllwing: 1. full frame phtgraphs f individual windws f the exterir. 2. clse-up views f intersectins f sills and frames (exterir) 3. clse up views f sash fcusing n bttm rail and muntins (if existing) 4. full frame phtgraphs f individual windws frm the interir 5. clse-up views f sills and bttm rails frm the interir. A cmpleted survey frm. (see enclsed) The survey frm dcuments the existing cnditin f the windws and identifies which windws will be repaired, which windws will pssibly be replaced, and what the prpsed new windw treatment will be. The frm indicates what the number n the drawing is and its crrespnding phtgraph number. The existing type dentes the material f the windw/dr and the type f windw/dr that it is. Fr example, WD DH wuld be wden, duble hung and MTL CASE wuld indicate that the windw wuld b a metal casement. The cnfiguratin wuld be the number f lights in the sash. Pssible examples culd include, twelve ver twelve (12/12), six ver six (6/6, r ne ver ne (1/1). There is als space fr additinal remarks when necessary. A fur level classificatin system is used t dcument the existing cnditin f each f the windws. This classificatin is based upn the system identified in the Natinal Park Service publicatin, Preservatin Brief #9, "The Repair f Histric Wden Windws." Class One,
"Rutine Maintenance," is assciated with small repairs, which are usually perfrmed as a part f a building's annual maintenance prgram. This may include paint remval, reglazing, weatherstripping, caulking, and repainting. Class Tw, "Stabilizatin, shws a small degree f physical deteriratin but can be repaired in place by patching, waterprfing, cnslidating, and regluing the existing material. Class Three, "Partial Replacement," has lcalized deteriratin in specific areas. These members are ttally remved and new nes are spliced int the existing fabric. In Class Fur, "Ttal Replacement," if the entire fabric f the windw has deterirated, then the nly feasible alternative is ttal replacement. On the survey frm under "Existing Cnditins," each sill, frame and sash is rated as t whether it is Class I, II, III, r IV. After all the windws have been rated, they are ttaled by class fr each f the windw elements: sill, frame, and sash are cmpared. Thse windws in Class I, II, and III, shuld be repaired and thse in Class IV shuld be repaired with exact duplicates. If the number f Class IV windws exceeds 75%, then ttal replacement may be apprved. Replacement The selectin f replacement windws shuld nt begin with what is cmmercially available, but rather with what is being replaced. A majr cncern with mst replacement windws is that they d nt accurately replicate the histric appearance f the existing windws. Replacement sash shuld match the histric sash in pane size and cnfiguratin, glazing, muntin detailing and prfile and histric clr and trim. Frequently, the prfiles f replacement elements, such as muntins, sash, frames, and mldings, are flatter and wider r narrwer and thinner than the histric prfiles. A stck windw may duplicate the exact number f riginal panes, but a change in relief affects the character f the histric windw, which in turn alters the verall appearance f the entire building. Therefre, windw sectins will be required fr all prjects invlving ttal windw replacement. In rder t cmpare the riginal and new prfiles, the fllwing infrmatin is needed: Full hrizntal and vertical sectins f the existing windws (3"=1'0") Full hrizntal and vertical sectins f the prpsed replacement windws (3'=1'0"). If histric windws d nt exist in the building and n evidence f the histric appearance can be lcated, then nly prpsed sectins are required. Windw sectins must be carefully detailed s that all parts f the windw are shwn and materials are specified. A sectin must shw the prfiles f muntins, meeting rails, sash, frames, and mldings. It shuld als shw the windw's relatinship t the existing wall. Belw are examples f vertical windw sectins f bth a histric and a replacement windw. The new windw's prfile clsely resembles that f the existing windw and therefre meets the Secretary f Interir's Standards fr Rehabilitatin.
Example: Histric Windw Vertical Sectin Replacement Windw Verticle Sectin Figure Figure 2 T summarize, wners are encuraged t repair the existing windws rather than replace them. If they existing cnditin f the windw, as dcumented by a windw survey, indicates that the windw has deterirated, then the windws may be replaced. All replacement windws will match the riginals as clsely as pssible and must cnfnn t the Secretary f Interir's Standard fr Rehabilitatin.
Replacements where there are n histric windws Histric windws make a significant cntributin t the character f mst histric buildings, but many rehabilitatin prjects begin with a building that has n histric windws. Whether new windws will replace nes that have been previusly replaced r will fill penings where windws are entirely missing, the new windws must be cnsistent with the histric character f the building. The existence f inapprpriate replacement windws des nt justify further replacements that are nt cmpatible with the building. The ideal basis fr the design f a replacement windw is the riginal histric windw. Infrmatin n the appearance f the histric windw can cme frm physical evidence that survives in the building r frm histric phtgraphs. Evidence f missing histric windws can be misinterpreted, hwever, and can lead t an inapprpriate chice f replacement windws. Especially when wrking frm infrmatin n a limited prtin f the building, it is imprtant t understand that all windws in a building may histrically nt have been the same. Just as the quality and refinement f masnry may differ between the façade and the rear r side elevatin, reflecting a hierarchy in the design f the building, the details f the windws may als vary, similarly reflecting issues f cst and appearance. It is bvius that refined face brick with tled, tinted mrtar is mre cstly masnry than cmmn brick with carse jints f plain mrtar. It may be less bvius that until the 1920 s a large-paned, 1/1 windw was mre cstly than a 2/2 r 6/6 windw. Prir t the mechanizatin f glass manufacturing, the added cst f a large piece f glass exceeded the cst f the wden muntin structure that supprted multiple smaller pieces f glass. Thus, a large, mid-19 th century huse might have 2/2 windws n majr elevatins yet have 6/6 windws n a rear wing; r a turn-f-the-century ffice blck might have 1/1 plate glass windws n street facades, but 2/2 windws n an alley elevatin. Glass size is nt the nly aspect f windws that may differ frm ne part f the building t anther. In urban areas where the spread f fire was a cncern, windws in clse prximity t ther buildings such as thse that faced a narrw alley were ften metal, instead f wd as wuld be typical n the primary façade. Thugh a single surviving histric windw can prvide the basis fr replacement windws that can significantly imprve the verall histric character f a building, such evidence must be evaluated in the cntext f the design f the building itself. The mre that is understd abut the factrs affecting the chice f windws, the mre likely limited histrical evidence can be crrectly interpreted.
"S U j Q) '2 "' 0 g. '2 "'1 0. Cf\ 01: j u. "'. t1j "' 0. YJ:. -..=,.. " u = '"0 =. "::1 "' " '#: '8