b'Frame-Out, Kerfed Brickmold Method for OldMetalFinned Windows with 2-1/4 or 2-3/4 Frame DepthCare always needs to be taken to avoid damaging the weather barrier under the old siding. Prying out old windows candamage the building paper and substrate. These methods allow proper removal of the old window and proper installationand re-establishment of the weather barrier avoiding leaks and potential moisture damage under the siding.Both old single hung and old aluminum sliders, often installed in astructure with wood or other lapped siding, or even stucco, should bereplaced by removing the entire old window down to the rough opening.As shown in the figure at right, the old wood window is anchored to the Oldstructure by nails through the brick mould casing.The old aluminum Single Old window is anchored by nailing through the fin, and then having the fin Hung Aluminumcovered by the siding or wood casing. Window WindowUsing a new construction vinyl window (with an integral nailing fin), thisalternative method of installation makes use of a wood block (preferablycedar), typically 1-1/2 by 1-1/2 however, any size that makes the jobwork well is what to choose.This block is attached to the integral nailingfin around the perimeter of the vinyl window frame.This block, in Exterioressence, replaces the brick mould casing of the old wood window, or the Brickmold Wood Nailingnailing fin and wood casing of the old aluminum window. Casing Casing FinCare needs to be taken to make sure that the new window with the cedar blocking fills the same opening dimensions of the old window that is removed.If necessary, cut back the siding for a more perfect fit,but if there is sufficient room, accurate measurement prior to orderingthe replacement vinyl window may avoid cutting back any siding.It is also important to make sure that there is a proper drip cap along theheader of the vinyl window with the blocking and that the entire perime-ter of the new installation is properly caulked to avoid water penetration.Installations using the rough framing can be done from either the inside or the outside of the home, but the blocking method must be donefrom the exterior.Cut back the siding to install the blocked window.1. Draw a line on the siding, 1-1/2 from the edge of the rough opening at the head, sill and both jambs. This will be the edge that theblocking will butt up against.2. Use a circular saw or Window Fitter oscillating tool to cut along theline (to cut through the siding, but not the sheathing or studs below thesheathing) and remove the siding pieces within the cut.Under some circumstances, the existing window could have beenremoved.If the existing window is still in place, and there is no casingcovering the window nailing fin, removal of 1-1/2 of siding shouldexpose the nailing fin of the old window allowing it to be removed.3. Measure the depth of the rough opening pocket from the edge ofthe interior trim (extension jambs or drywall return) to the outside edgeof the wall substrate (sheathing or similar) against which the blockingwill be seated. The common measurement will be between 3/4 to 1.Whatever the dimension, it is the measurement that will determine thelocation of the slot to be cut in the blocking.Window Fitters Guide to Window Installation862020 AWDI, LLC Do not reproduce without permission'