Expert: Bruce E. Johnson - 3/11/2010

Question
After successfully tackling interior remodeling in our small 25-yr. old home, my husband and I wish to add additional living space by enclosing a large existing covered patio. We think we want to use 2-3 courses of block as the wall base, then finish with wood framing and windows.  How should we tie the block to the slab?  How should we tie the wood framing to the block? Once we get into the wood portion, my husband is pretty comfortable with code requirements and construction methods, but block construction is new to us (and we are eager to learn more.)  We are in Arizona, so moisture is not a serious problem.  

Thanks in advance for any input you can offer.

Answer
Hi Mary, The easiest way to attach block to concrete is to drill a hole and epoxy pieces of #4 or #5 rebar into the slab where your fill cells are located in the block 3-4" of penetration is all that is needed and you can find concrete anchor epoxy at most hardware or big box lumber yards.  Then you fill the fill cell up with concrete and that will lock the masonry to the slab.  CMU's or concrete masonry units (cinder block) can be purchased in a U-block as well.  This U-block is used as the top course of the knee wall, a piece of #4 or #5 rebar laid in the U and the U is filled with concrete.  While the u block concrete is wet you place 1/2" anchor bolts into the concrete for use in attaching your walls.I hope this information helps, please feel free to write again regarding this or other matters. Sincerely bruce e johnson..bejohnsonconsulting.com