Creating an opening in existing masonry wall

[fromtherafters]

Putting a doorway in an existing 10" CMU wall. If this were new construction we would place reinforcement on either side of the opening, parallel to the jamb. What is typically done for placing a door in an existing wall?

Thank you in advance.

 

[KootK]

Depends on the size of the opening and the load demand. Options include:

1) Run some numbers and do nothing.

2) Cut some blocks vertically and install new bars (difficult).

3) Install some backup steel behind the jambs (ugly).

4) Over cut the opening and infill with reinforced blocks (pretty).



I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[Ingenuity]

5) external FRP.

 

[jayrod12]

Or steel lintels extending beyond the opening. Also ugly but sometimes the easiest and quickest solution

 

[MotorCity]

If its just a man door (not an overhead door) and you don't have any unusual or large loads near the opening, you probably don't need to do anything. See if you can take advantage of arching action.

 

[fromtherafters]

Thank you for all of the feedback. We are only talking man doors. I just wanted to make sure there weren't any standard practices I was missing.

As always, you all are very helpful.

 

[SLTA]

Hang on a second - how old is the masonry? That can make a big difference in what method of support is appropriate.

Please remember: we're not all guys!

 

[msquared48]

"We are only talking man doors"

If any major wall steel is cut for the door, as in column steel in the wall from a beam above, this is not "just a mandoor".

The cut steel will have to be compensated for...

Mike McCann, PE, SE (WA)

 

[fromtherafters]

SLTA - Building was constructed in 1980

msquared48 - I agree. If we were eliminating a major support such as a column, we would need to make other provisions. I do apologize for not provided enough information at the beginning of the post.

Please don't think that I am taking what is said here as gospel and running with it. I wanted to make sure there were no industry practices that I was missing. Calculations will be made and the load paths will be analyzed.

 

[KootK]

I wanted to make sure there were no industry practices that I was missing.

Amen. Half the battle is figuring out what "normal" looks like in any given situation.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[Ingenuity]

We are only talking man doors.

Please remember: we're not all guys!

Let's call them gender-free doors

 

[msquared48]

A reaction to that recommendation hinges on whether you view the opening from the right or from the left.

Mike McCann, PE, SE (WA)

 

[theonlynamenottaken]

Interesting spectrum of responses to the OP. Though the original post was a bit vague the statement,

place reinforcement on either side of the opening, parallel to the jamb

shows that the OP was referring to the wall's resistance to out-of-plane loads. Some people proceeded to give recommendations for that, some for in-plane gravity loads over the opening, then gender jokes. Vewy intwesting.

Food for thought on unvoiced concerns...
Does the masonry span vertically only for O-O-P loads? Horizontally only between pilasters, etc? Both? It matters...
Is it a shear wall for the overall LFRS of the building? If so this gets awfully tricky and may dictate where the door goes or it may culminate in deciding not to cut in a door at all.