Block up cinder block window.


Old 10-17-15, 06:34 AM
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Block up cinder block window.


I want to block up a cinder block wall old window opening. I am trying to find out the best way to attach the top block to my wooden sill. Do i put mortor on top of the blocks to fill the space or is there another product that should be used to make contact to the wood.

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Old 10-17-15, 06:41 AM
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Post a picture.
Is there a steel lintel of some kind over that opening at the top?
Old 10-17-15, 06:54 AM
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No steel.Name:  image.jpg
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Losy picture tough light. Window is 24x24. Want to use top cap blocking. Rotate picture 90 degrees
Old 10-17-15, 08:13 AM
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The top block usually will have a sill sealer gasket so that the joint between the wood framing and the cement block doesn't create a draft. Old construction will be like a thin 1/4" thick fiberglass/kraft paper ribbon... newer construction most often uses a white 1/4" thick foam gasket. You can pick up a roll of that at the box store and staple a piece of that to the bottom of the sill plate (above the window).

Probably the easiest way to mortar them in for a novice block layer like you or I might be... would be to set a few small pieces of plastic shims on the centers of the cement opening... then set the cement blocks on those shims. You would shim the 2nd course of block the same way... but you will want to shim that top block tight up to your sill sealer gasket that you stapled up on top. The shims should leave about 3/8"-1/2" of space for you to tuck point mortar all around the edges of all the blocks, inside and out.

You would want a tuck pointing trowel, and also a brick jointer tool in order to pack your mortar into the joints and to smooth the surface.
Old 10-22-15, 01:48 PM
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i'd use backer rod & sealant rather than mortar

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