Nudura - Air Brick Placement...

[Mulberry View]

I'm just planning my Periscope Vents. My design is very complex in terms of levels, so I'm having to really engage my brain to get the heights right on each face of the building.

 

I started wondering if I should be positioning the external vents to line up not only with the coursing of the brick slips, but the horizontal spacing too? Is that too ambitious? What have others done?

[Russell griffiths]

Nobody else having a go so I will stick my oar in. 

I would put your periscope in but make up the opening part that takes the airbrick larger than needed. 

If you do some sums you can work out the difference between a full brick and halfbond. 

So your opening letter box will be a brick and a half long, then when you put the slips on you can get the position right and cut a blank plug of eps and glue it in and put your slips over the top. 

[Mulberry View]

Thanks @Russell griffiths. I've since started placing the vents according to measurements. Here's what I've done.

 

I took an overall measurement of the wall, allowing 30mm 'overspill' on the length of the wall to account for the return on the slip (23-25mm + 5mm adhesive), then 195mm for the first brick. From there I was able to use 225mm brick gauge to decide on the vent position. I've opted for a vent every 10 bricks, roughly. There are many thoughts on how many vents, but I have several locations where vents are impossible, so I think this placement leaves around 2m between vents and I'm fairly happy with it.

 

Some of my walls were designed with perfect brick gauge spacing (taking into account) the 'overspill', but some aren't quite right, so in those cases, I'm going to gauge from the corners and allow for any cuts to be within a door/window opening so that later on we can decide how to make up the discrepancy. The majority of the visible vents will be nicely spaced, but honestly, the level of thought needed for these in our design is boggling.

 

I was able to space the majority of the vents so as only to need one set of webs cutting, but to make the above spacing miss all the Sleeper walls (essential) and avoid only cutting one set of webs (ideal, but not essential) is just too much.

 

Leaving this here in case it helps someone else.

 

Now I just have to figure out how to plug the vents to stop them collapsing, but with something that can be removed afterwards if we decide to lay the B&B floor before the first pour. Answers on a postcard.