# Forum Home Renovation Brickwork  Cutting an opening into a single brick wall

## villageidiot

In the rear wall of my garage there is a single brick wall with a small opening in it, which is just big enough to crawl through. When I crawl through the opening I am in another small 'room', about 2m deep x 2.5m, which holds a few pipes for the laundry, floor and toilet wastes upstairs. 
The ceiling of my garage/this 'room' is the underside of the concrete floor slab from upstairs. 
I was thinking that rather than wasting this space, I could cut a doorway sized opening into the wall and use the extra space for storage etc. 
Would there be any issues/problems in doing this? The wall where I want to cut the doorway used to be load bearing but no longer is due to a wall which was once directly above being removed and a lintel installed. 
I thought I could hire an electric masonry/demolition saw and remove the mortar by cutting a horizontal line between 2 course of bricks at the height I wanted the opening, then insert a flat bar lintel, then make two vertical cuts at the width I want from the underside of the flat bar lintel to the floor where I want the door, then remove the bricks. I was thinking of making the opening about 1200-1500mm wide. 
It sounds quite easy! Would this be the easiest way to do it, or can anyone think of a better way or of any problems that could occur? 
Also is installing the flat bar lintel absolutely necessary? If not, how many courses of bricks should I leave between the top of the opening and the underside of the slab so as not to compromise anything? 
Thanks in advance to any suggestions!

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## terrance essex

if you can I,d leave 4 to 5 bricks above the door way & rather than flat bar
use one heafty angle type the thickness of the bricks (5" or so) I,ve
done similar to accomodate fridges but had a third of the wall still above
(better to much than to little !...regards Terry

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## villageidiot

Thanks for the advice. 
Has anyone any experience with using one of these for such a job? You can get hire them from Kennards.  http://icsbestway.com/en/documents/I..._Datasheet.pdf

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## Bloss

They work well, but just as are the most commonly used alternative 9" angle grinders are a dangerous piece of kit! I reckon that the grinder with diamond blade is a more controllable device, but great care is needed and full protective gear - so mask and face shield leather gloves at a minimum.

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## villageidiot

Thanks Bloss, but when you say 'commonly used 9" angle grinder' and 'grinder with diamond blade is a more controllable device' do you mean a normal angle grinder with a diamond blade, such as this   
or a demolition saw such as this which uses water to cool the blade and prevent dust?   
If I use just a normal grinder with the diamond blade, wouldn't that be extremely dusty (not to mention  quite a bit slower), or does the diamond blade reduce the dust compared with using a normal stone/masonry blade? 
Also the Arbotech saw you mentioned in the other post, can that be used for actually cutting through the bricks, as my understanding was that it is designed for cuttiing through mortar only? - to remove whole bricks from a wall for example.  AS170 Product Info

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## Craigoss

I've had to cut many brick openings in my place (generally to widen doorways). 
You have a few options how to cut it: 
1) If the wall is single brick and you have a 9" angle grinder (with a diamond blade), run a cut up the wall. But seeing as though a 9" blade will only go about 2/3 through the brick, you will need to get on the other side of the wall and finish off the cut. Bit over $200 for a good makita 9" grinder, then add $50+ for a basic diamond blade. 
2) Otherwise you can use a 12" wet saw, which will just rip through the wall in one go and make alot of mess. Hire these from kennards etc. I've had to borrow a 12" wet saw when cutting through a cavity wall when I couldn't get to the back of the bricks to use the 9".

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## autogenous

100mmx150mm x 8mm Lintel with at least 150mm bearing either side.  Put the lintel in from the back so you don't see the spine.  Make the opening no bigger than 850.  Check the Slab above isn't supporting any walls over the opening? 
Do you have a picture for us?

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## villageidiot

Thanks for the suggestions so far. Here are some pics.  In the first 2 pictures/attachments you can see the wall in my garage which I have discussed in earlier posts - the wall I want to remove. (I couldnt stand back far enough to get the whole wall in, but it gives you an idea) The red line shows where I was going to make the cuts, and the black line shows where I was planning to insert the lintel.  The 3rd picture/attachment is directly upstairs in my kitchen, showing where a wall once was, that has obviously since been removed. (It sat on the slab directly above the wall downstairs in the garage in the first picture). You can see that a lintel has been installed to hold up the ceiling ( the floor of the unit above). There is another wall directly above the lintel in the unit upstairs.  Given that the wall which was removed in my kitchen is no longer there, can I assume that the wall I now want to remove in my garage (pictures 1 and 2) is now NOT load bearing, with the weight above being taken by the lintel? (picture 3)  If this wall is NOT load bearing, would I be able to remove the wall completely to the ceiling and not need a lintel? Or should I use the lintel and keep three courses of bricks above it just to be safe?  Also would there be any issues with inserting the lintel into the inside course of bricks of the outer wall as shown by the dotted line in Picture/attachment 1, given that the weight of the unit upstairs from me would now be pushing down through that wall as a result of the lintel being installed in my kitchen? (Picture/attachment 3)   The width of the opening as shown by the red lines would be about 1.6 metres.

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## Bloss

mmm - unless I am missing something that wall has a concrete slab sitting on it? Sorry to disappoint you, but that makes it load-bearing. Autogenous is probably right, but I'd be getting specific advice from someone who has a look onsite, not just the friendly folks on here, before I started cutting anything.  :Frown:   
And I meant a regular 9" grinder as in the 1st pic - with diamond saw. You can buy an Ozito or equivalent el cheapo that'd do that job for under $100.

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## villageidiot

Yes, there is a concrete slab on it, what you see in the picture is the underside of that slab which is my kitchen floor, which is directly upstairs. But I am confused as to how the wall may be load bearing (apart from just the weight of the slab) given that there is no wall/load above it now, only empty space? In picture 3 you can see where a lintel now replaces where the wall directly above the wall to be removed once was.  
I thought that the load would now be only at each end of that lintel, pushing down through the inside course of bricks of the external wall on the left hand side, and down on another wall on the right hand side which has not been removed, and has a wall directly under it in the garage which is also not being removed.

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## villageidiot

I have attached some floor plan photos which I hope will make it easier for you to determine whether the wall I want to remove is load bearing or not, and what sort of lintel (if any) etc it would require. The first photo shows the garage and storeroom with the wall I hope to remove, shown in gray. The 2nd photo shows the floorplan directly above.

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## Bloss

> (apart from just the weight of the slab

  Que?  :Eek:  What do you reckon is holding up the slab? How light do you reckon the slab is? This is not a wall I would be cutting into without first getting an engineer telling me after a site inspection what I need to do to get it done safely.  :2thumbsup:  It is quite possible they would tell you that the slab is sufficiently supported and reinforced through to the other walls and all is ok, but that's not to be assumed.

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## villageidiot

Thanks Bloss for the advice which I will take. The slab is obviously being held up by the walls! 
But note that the same slab continues across and also forms the ceiling of my garage, where the unsupported area/span is much bigger, (5.5m x 3.75m = 20.65sq metres), than the unsupported area/span above the storeroom ( {2.85m + 1.45m} x 2.35m = 10.105 sq metres when the wall is removed), so I would be surprised if removing this wall would cause a problem to the support of the slab there.

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## Bloss

You might well be be right as I said - in any case you will probably be able to support the slab on one side and remove the wall from the other. But check it out 1st.  :2thumbsup:

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