b'Once a curved masonry header member is created, the installation steps are basically the same as for rectangular windowsFree Foam CellularCellular PVC archedpvc can be arched Header bucksmoothly to make thebest curved buckSmoothly ArchedCellular PVCHeader BuckSeal JointKerfing - cutting multigrooves in wood tofacilitate bendingAlternate wood frame methodWherepoured header, with curved inner surface, is not Wood Constructed provided, a wooden section is built within the rectangular Header Openingopening, having a curved surface to which the window with arched woodbuck is mounted. This method is often used toblocksmatch CMU walls with wood frame walls. Because bending a wood buck is difficult, this method is Kerfed Curvedbetter suited to flush mount, finned windows. BuckBlocks are fastenedin a rough arc towhich the kerfedbuck is to be nailedIt is difficult to kerf wood whichoften creates a poor header buckWindow Fitters Guide to Window Installation133 2020 AWDI, LLC Do not reproduce without permission'