BEFORE THE ARCHITECT – CUSTOM HOME DESIGNING BACKGROUND – HOUSE DESIGN ARTICLES

ALL ABOUT HOUSE FOUNDATION PROBLEMS and YOUR HOME DESIGN FOUNDATION PLAN FOR A MASONRY LEDGE OR MASONRY SHELF OR BRICK LEDGE OR MASONRY WYTHE WALL SHELF  OR LEDGE

By Before The Architect  Copyright 2009

YOU MAY FREELY QUOTE THE AG WITH PROPER ATTRIBUTION

MASONRY OR STONE OR BRICK SHELF OR LEDGE HOME FOUNDATION PLAN GUIDE DETAIL

Introduction

          A home foundation masonry shelf or masonry ledge holds up the weight of the masonry piled on top of it, or at least, makes for that appearance.  For full-depth masonry clad - these days, about 4 linear inches thick for either natural stone or brick - a masonry shelf or masonry ledge is functional - it supports the veneer of the masonry clad.  For thin-cut or thin stone and for thin brick - these days, about 3/4 linear inch to, say, 1 1/4 linear inches thick - a masonry shelf or masonry ledge is decorative - the faux wythe is adhered to exterior wall.

What's in a wythe? 

A single wythe, i.e., a single width masonry wall of any masonry material, shall be supported along the entirety of its footprint by foundation as a masonry shelf or ledge.  The masonry shelf is in wall and footing not less in construct than the structure to which it is attached and is contiguous with the foundation of the structure to which it is attached either. 

A masonry shelf can be a monolithic placement, or it can be a retro, brick or block layup durably fastened to existing concrete block or other masonry wall buildup and durably fastened to existing the footing. 

A masonry shelf shall extend not less than evenly revealed on the horizontal on both sides of the foundation walls. 

The footing shall be in thickness not less than foundation wall width and in width shall be not less than twice footing thickness or twice foundation wall width.

The masonry shelf itself shall be reinforced by not less than 2-#5 Grade 50 deformed rebar continuously on the horizontal with not less than ¾ linear inch and not greater than 3 linear inches plus maximum aggregate diameter cover whether as tie beam or bond beam. 

A masonry shelf shall be at the top of its face not less than 6 linear inches above finish grade level and not less than 1-2 linear inches below interior slab-on-grade top of face, or, less preferentially, not less than 1-2 linear inches below concrete curb on which would rest a framing mudsill atop a slab-on-grade, the latter being potentially less resistant to moisture intrusion.