UKC

A question for the UKC collective's boundless knowledge & experience - surely I'm not the first person who's ever wanted to do this...

I need to fill the "triangular" spaces between the tops of existing bricks and some sloping roof supports. Ideally I'd like to fill these spaces with brick "wedges" - they don't have to be super-exact, just roughly right so that any remaining gap is small enough (either I'll fill with mortar or just leave).

Will I be able to use an angle grinder to cut down old bricks into these wedges or will they keep on breaking up as I try this?

And, if it is ok, is there a sort of minimum thickness of brick below which it's not even worth trying because it's always going to break up?

[These "triangles" will mainly be 4 sided, with a sloping top, but the low end may get pretty close to zero height (or actually be 0 - real triangle) in my plans - which don't yet take practicality into account]

In reply to Michael Hood:

Angle grinder with a diamond wheel cuts brick easily. A 4" grinder making a cut each side leaves you with a bit of hammer work to finish the job. 9" grinder would be better but the cost is much higher and I'm scared! A wet tile saw works equally well and makes less dust, I'd hesitate to say less mess.

jk

In reply to Michael Hood:

It's doable, but dusty and time consuming. It might be easier to either cut wooden wedges, or notch a few lengths of suitably sized wood with sloping notches at suitable spacings so they can be pushed into place to sit horizontally on the top course of brickwork.

Can I ask why you're doing this (I'm assuming this is on the inner course of brickwork)? The roof should be adequately supported on the outer leaf of brickwork, and it's good to have a bit of a gap to vent the cavity wall and get air into the loft.

In reply to Michael Hood:

Notch the roof supports, so more wood makes contact with the brick. If not, then just make wood wedges. 

In reply to summo:

An angle grinder with a stone cutting blade will do the job but a large (9"+) cutter will be much better, you can hire these and is worth it if you've a few to do.

Or you could do the easier thing of dusting the voids, spraying with water and filling with squirty foam... 

In reply to Ridge:

Thank you to everyone who's responded.

Brick (single layer) shed (maybe an anderson shelter originally) which I re-roofed over the winter (really, really stupid time to do it) with a sloped polycarbonate sheet roof - all ok. This is just filling the gaps on the ends.

Want to try filling the gaps with brick (because that will visually fit best with what's there now and be longer lasting), but if that fails the fall back plan would be to cut a wooden "board" (100-150mm deep) to run down the "slope" covering the gaps on the outside.

In response to other's thoughts:

• there will still be plenty of ventilation,
• these bits of brick aren't required to support anything (although they may share the miniscule load wherever the gap becomes zero),
• wooden wedges would be more complicated than using a "board" (as above) although easier to deal with than brick.
• foam filling won't look so good since this is external and probably not as long lasting
• functionally, I could probably ignore the gaps because rain hasn't come through the gaps yet (maybe I judged the size of overhang correctly)

In reply to Michael Hood:

My point was more if you have say a 6x2 common or principle rafter coming down, it shouldn't just sit on the very edge of the brick. Where they effectively only make a few mm of contact. One needs angling or notching to spread the load. 

In reply to Michael Hood:

genius! the sign of a master craftsman

only kidding, but I'm struggling to picture what you've got; didn't you do a normal bird-beak joint where the rafter sits on the wall?

anyhoo;

as above - angle-grinder with diamond blade; the more expensive blades are noticeably better but if you've only got a few wee cuts it's no issue. cut cleanly where it's visible, bosh the rest out with a hammer and cold chisel if need be.

min thickness of brick, depends on the brick really but I have seen modern brick cut diagonally through so....

if you're doing this: do it outside, preferably in a windy spot, away from the washing-line and close nearby doors and windows. and wear a well fitting mask !! . a diamond blade creates a LOT of very fine dust which gets everywhere.

In reply to daWalt:

Thanks for the dust warning, I was sort of expecting dust but I'll make extra sure to get it right.

Description, hope it makes sense...

The shed has 2 long walls, one is 3 brick courses higher (*). Both have a 95x45 timber along the top. There are 4 50x38 timbers sloping down across the shed supported by the "top" timbers which have angled cut-outs in them to semi-recess the sloping timbers.

The 4 sloping timbers have the polycarbonate roof attached to them. The two outer of the 4 are above the end walls.

(*) - I had to take everything above the level of the lower long wall off (tiled roof with masses of rotting timbers - weighed loads), then built up the brick on the higher long wall and all the complete bricks (plus a lintel above the door) on the end walls that would fit under the sloping timbers. The remaining gaps under the sloping timbers on the end walls are what need filling. The roof angle is very shallow (~10 deg), if it was more steeply pitched then this probably wouldn't be an issue.

I suppose I could have bird-beaked the sloping timbers (is that what you call it when you do a shaped notch) and screwed straight onto the long brick walls except that the middle section of the lower long wall is glass blocks rather than bricks, so it needed something on top of that anyway that could be attached to the brick bits on either side. Also, I think I would have needed deeper sloping timbers (than 38mm) to have bird-beaked them without introducing a significant weak-point (they extend about 150mm beyond the walls to support an overhang) and the new roof is light so doesn't need heavy timbers to support it.

In hindsight, I might have done things slightly differently, but I didn't have loads of experience to know how these things are normally done, just enough ability to know that I could put something solid together that would work.

In reply to Michael Hood:

sounds like you're planning to cut quite a few bricks, I originally thought you were you were only looking at 4 corners.

from what I can picture, it would have possibly been easier to build the wall up fully, draw a chalk-line across it and cut to the line in-situ (but that's possibly no real help at this moment in time..)

I'm sure what you're trying to do is possible, but if you need to have one cut line up with the previous etc, it might get a tad fiddly.

personally, I'd wack a timber edging board up to cover it - much quicker. (or a combination thereof - some brick to cover the deepest gaps and minimise the depth of edging board)

this applies to very near everything, if it works it works - it's a shed

on masks: I was cutting a lot of concrete the other week and got myself a GVS elipse 1/2 mask (other brands are available). this type, rubber mask with replaceable filters, are infinitely better than any disposable type. with a clean shave, good seal, all day in the dusts and it won't even tickle you're nose-hair. 

In reply to daWalt:

I'm going to jump on the mask thing. Brick dust is nasty stuff and very fine, invest in a rubber seal mask with a cartridge filter. I favour the JSP press to test myself. You can press on the filters to close the airway and when you can't breath you know its sealing well. 

In reply to Michael Hood:

What type of brick? If they don't have a frog (scoop bit) and they are strong, maybe you can hire a block splitter if you have a lot to do

In reply to daWalt:

Yep in hindsight this sounds like a good idea but the urgency was to at least get the roof on. Technically, I could dismantle the roof and do that because it's all basically just screwed together but I can't see that happening.

Doesn't have to be too precise - have you seen my bricklaying 😁 - they're all old bricks so the rows aren't level in the way you'd expect on a new build house (another lesson I learned, old irregular bricks are not the best place to take your first steps in bricklaying).

I may very well end up doing the combination if the smaller brick wedges end up being to difficult or fiddly to get right.

Thanks for the advice.

In reply to CantClimbTom:

Most of them haven't got "scoops" but they're old bricks so the strength is unknown, and I would guess quite variable since the bricks have a range of appearance/colour, etc.

I worked out I need at most 5 wedges on one end and 6 on the other end - that's if the thinnest ones are doable, otherwise it's probably 3 & 4.

In reply to Michael Hood:

You could hire a whizzer with a diamond blade for the day. 

In reply to Dax H:

aye, without a good seal any mask is duff - it's all the excuse I need to go for the handlebar mustache look

In reply to Michael Hood:

Could you perhaps fill in the gaps with wood (or something else), and then paint a black stripe under the roof line to hide the difference in materials?

In my mind's eye, black wouldn't look to odd against brickwork. If you can't sort it - hide it.

In reply to jkarran:

A 9” grinder is about 10x more scary than a 4” one! I recently gave away mine to my (younger and stronger) nextdoor neighbour because I didn’t feel safe using it!

In reply to Michael Hood:

Hang on... we're talking making 11 cuts at most, 7 cuts at least

Not sure we need to go to hire shop and call in the cavalry. You could just get a tct tile cutting blade for a hacksaw (hacksaw, not junior!) and saw the first 1/8th way through then use a bolster and lump hammer to finish the cut with a sharp strike. For this few number you could probably sacrifice/ruin an ordinary hacksaw blade if you have a spare and not even bother to get the tct one

For only so few wedges we've been over complicating this!

In reply to CantClimbTom: I was wondering about hand sawing while going to sleep. If the job was spread out over a few weeks, it'd not become as irritating as it might do if approached all at once.

In reply to Rog Wilko:

Yeah, the 9 inch grinders can be a bit scary, especially with a 1mm cutting disc in them.

I much prefer my 4 1/2" grinder

In reply to Michael Hood:

You need a 9" grinder with a general purpose diamond cutting disc in it.

In reply to Rog Wilko:

I used to have a 350mm petrol disc cutter. You learn very quickly not to move it around while the disc is spinning due to the centrifugal forces - almost fell over!

In reply to scratcher:

I remember a family friend cutting up some thick slate with one of those on our lawn while wearing trainers, and my Dad mentioning thinking 'One slip, and you lose your toes'. 

In reply to CantClimbTom:

Thanks, hadn't thought of that - sounds like the first thing to try - I can nick my dad's full size hacksaw - I've been borrowing his tools for years if it's something I don't have - and at nearly 98 I can't see him using (or being allowed to use) that again 😁

I presume if I do parallel cuts on both sides of the brick, then it's much more likely to shear how I want when I give it a whack with the bolster.

In reply to mwr72:

That's not your Mrs says ...

In reply to Maggot:

I'm wondering why your Mrs gave you your username?...

In reply to Michael Hood:

If it's just a shed, fix a board to the roof timber to cover the holes then forget about it.

jk