Expert: Bruce E. Johnson - 2/19/2009

Question

I'm wanting to cut a opening in a cinder block wall  block to install a standard hollow metal door. How should I start and what tools will I need?

Answer
Hi Robert, you will need a concrete cut saw of some sort.  You can rent one that is gas powered or electric.  Make sure your rough opening dimensions are good and double checked before beginning the cut.  If your wall has a bond beam or header beam at the top of it then you might not need to add a reinforced header over the door.  If you need to reinforce your header over the door you can do it with a steel angle iron 6x6x 1/8" x the width of your rough opening plus eight inches.  Overcut your horizontal header cut 6" past the width of the vertical cuts on each side and then slip the angle into this cut and attach the angle with tapcons prior to removing the masonry.  Don't overcut your vertical cuts as this will weaken the header material.  You may need to take a grinder after the bulk of the masonry is removed and get that last little bit of block cut out underneath the header.  You will need a drill and a concrete bit do drill for the door anchors and generally a 5"-6"x 3/8" sleeve anchor is what you use to attach the door frame to the masonry.  In some cases you may need to open up the fill cells on each side of the door at the top and pump concrete or grout into each fill cell prior to installing the door frame for added stability.  I hope this information helps feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com