I need to cut a 42″w x18″h hole for a heating/AC unit in a concrete block wall with brick veneer on the outside. One story building, bar joists under a built up low slope roof.
I live where it is doubtful I could find a company that would cut this for me. I might have access to a diamond blade chainsaw, but that might not pan out.
How can I go about cutting the hole?
Any guidance on what sort of lintel needs to be installed?
How did I get talked into this?
Questions abound.
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Replies
well i would try to at least line with as many mortor joint as poss.
then fire up a quikie saw and diamond blade.
have fun
YOU ONLY NEED TWO TOOLS IN LIFE - WD-40 AND DUCT TAPE. IF IT DOESN'T
MOVE AND SHOULD, USE THE WD-40. IF IT SHOULDN'T MOVE AND DOES, USE THE
DUCT TAPE.
i see your in kansas,call kansas concrete here in wichita. they travel the whole state . when they are done it will look good.
YOU ONLY NEED TWO TOOLS IN LIFE - WD-40 AND DUCT TAPE. IF IT DOESN'T
MOVE AND SHOULD, USE THE WD-40. IF IT SHOULDN'T MOVE AND DOES, USE THE
DUCT TAPE.
What kind of equipment do they have? I saw a rig on TV where the saw would run on a track system. I've been asked about installing some basement egress windows and something like that might be the ticket.
yes,they have a track system that they fasten to the wall,then hook the saw on it and cut. the cut is very straight and true.
i had them cut a basement wall 3' x 7' for a door.seems like it was 250. then i paid them another 75 to knock it out of the hole. i thought that would be tough as it probably weighed 1800 lbs. took the guy about 5 minutes with a sledge,tapping it on each corner. turns out i should of done that part.YOU ONLY NEED TWO TOOLS IN LIFE - WD-40 AND DUCT TAPE. IF IT DOESN'TMOVE AND SHOULD, USE THE WD-40. IF IT SHOULDN'T MOVE AND DOES, USE THEDUCT TAPE.
I did something very similar only I rented the equipment and it cost me $65 dollars. took about 45 minutes..
Cool! Thanks.
Any guidance on what sort of lintel needs to be installed?
42" wide means you need at least 50" lintel (either precast or block lintel) in the block. That is 4" over size on each end of the cut, but 42" is not an even block break so you need to land at least 4" of lintel on the end of an uncut block, or half block. An 8" lintel bearing on each end would be better. Ideally the lintel should be transfering the load through full or half blocks, not cut blocks, to the foundation. Depending on how much building load is above your cut, you may be able to make do with less than the ideal.
The lintel for the brick will mean taking out two courses above your top cut line and installing attaching the steel lintel to the block lintel/wall and re laying the two courses back on it. The brick lintel is supporting the brick load only while the block lintel is supporting the building/roof loads.
I would adjust the placement of the block cut hole to make the extra 2" of the 18" cut land at the bottom of the opening. That will keep the top cuts on an estiting bed joint and make the lintel placement work out.
On a job like that I ussually start from inside the block wall. Make those cuts and lintel installation first using a block saw and angle grinder with diamond blades to clean everything up. I then knock out a few brick in the center of the block opening and move outside to cut or take out the remaining brick to match the hole.
Thanks Dave. Is there any way to sneak steel into this without removing the courses above?
Is there any way to sneak steel into this without removing the courses above?
Nope.
You have to get the "leg" of the angle up into the space somehow. And, you are making a pretty big opening into a block wall, which is largely hollow. Spanning four block wide usually wants for a lintel course, which would be hard to get concrete into without carving o nthe block courses above.
Which does not leave a lot holding the brick up outside. Now, you do have an advantge, you are going to have a surplus of brick exactly matching what is there in age, fading, color, texture, the works.
Now, you can go with a metal lintle angle on the inside of the block wall, but you'll need a welded-up T to carry both the block and the veneer brick on the outside face.
Masonry walls are solid, but only when solid; start making holes in them and it's Jenga only in stone-hard materials.Occupational hazard of my occupation not being around (sorry Bubba)
The guy installing the units is going to get back to me with what the sleeves look like. He says they list a "trim" kit but was unsure of what it consisted of.I'm thinking that the up part of the angle wouldn't matter if it showed on the inside or possibly the trim kit might hide it. Not sure about the outside.Thanks
Thanks
Almost said "no sweat" but masonry is a sweaty job <g>
Still one of my favorite materials to build with and work on. Detailing can be a pain, but, hey there it is.
I'm really picky about drawings with masonry, too--comes from having used carstock and plastic brickscales one too many years of my life. Little things like dimensioning column bases to be 30" instead of 28" or 32" (doubly so with CMU).
Getting it right is really pretty easy. Which is why seeing it wrong bugs me so.Occupational hazard of my occupation not being around (sorry Bubba)
It's funny how a job changes someone's perspective. I knew a guy who tooled block joints for a mason for awhile. He said for months afterward every time he saw a block wall he inspected the joints and was upset if he saw a bad one.
>>Getting it right is really pretty easy. Which is why seeing it wrong bugs me so.
Amen.
I hired a couple guys to lay the block on DW's kennel building. It is a T shaped building and I set 1/4 pins at all the inside/outside corners. Small building and only 4 courses of block, so they layed it up in less than a day before I got home from work. Something didn't look right on the down leg of the T side. The block was crowding the edge of the footing on one side and dead center on the other. They layed up the squarley looking side on the wrong side of the layout pins.
Try to idiot proof something for some people and they still find a way to screw it up. I got 8" by 15' more floor space out othe mistake, but if the trusses had already been ordered I would have had a mess to deal with.
That's one of the reasons I DIY everything.. mistakes are my fault and I try not to make any. ICF's make foundation work so simple and easy it's something a guy can do himself and save money plus get it done the way he wants it!
Frenchy, you assume to much sometimes.
Installing an ICF foundation and then burying all but the top 8" for a slab on grade would have been a major waste of resources in both material and money.
I normally do small foundations like that myself. In fact I added another course to the foundation and my work was better than the guys I paid to lay block, but that is not the point.
No matter what you think you are saving, there are times when it makes sense to sub some work out. I might have saved the $400-$500 I paid those guys, but it would mean a two weekend delay in pouring the slab and starting to frame the building. While you might think of that time as no significan delay, I did. There where six dogs being kenneled in my shop and they needed to be in the new building asap.
Giving advice based soley on you personal experience is fine in some cases, when the details of a project are given. But, applying your expeience to someone elses situation that you don't know a thing about comes off as a "look at me" brag. I don't mean that to offend you. It is just my point of view.
I'm sorry. Somehow I answered another post here. My error.
We weren't talking about slab on grade we were originally taking about cutting a hole in concrete. I answered that with my experiance with rental equipment and what it cost me earlier..
"I'm really picky about drawings with masonry, too"
I wish more people were. In a previous life I worked for an architectural precast concrete outfit and I was surprised by the lack of detail and outright errors in drawings from big A/E firms. Had a batch of wall panels, made to the specs on the prints they, the GC, supplied. Got a call from the GC screaming the weld plates were on the wrong side of the wall- who ever drew the prints used a solid line instead of a dashed indicating the weld plates. On another job (a small hospital) we were to supply lintels and sills. The lack of detail was stunning- the window schedule was a joke and the A/E firm (located 2000 miles away) was next to useless in supplying missing information. Finally sat down with the masonry contractor and contacted the window manufacturer and got the job done.
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CapnMac gave you the answer and explanation.
Thanks again for your help.
Hilti makes a concrete cutting blade that goes in a recip saw.
Tu stultus es
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Look, just send me to my drawer. This whole talking-to-you thing is like double punishment.
Thanks. I'll look it up.