Went to 2nd fix a fan today ..............

[phil d]

We're all grumpy when it comes to things like that . 

A right argument on one job some years ago ,  wiring a new build doctor's surgery  under the control of  B,ham City Council  .  

Part of the spec was the alarms ,installed by one of the big well known companies whose name escapes me now , were our sub-contractor .             Near to finishing my 1st fix we get them in for their 1st fix. 

I go to another job for two days , on return  the City Clerk of Works is there , doing his nut .        Alarm wires are through the same ceiling joist holes as my wiring ..but .. the annoying part....  the Clerk says you better get your wiring  moved , you can't have it enclosed with low voltage    ( At the time Low Voltage meant below 110 v ) . Like I didn't know that !

I phone my boss , who phones the alarm firm , who say we only make one call to fix , you'll have to move  your wiring   :C    We are specialists  and we work to BS  whatever !   Not your Regs .  

So bloody annoying that once again  we get it in the  neck ...I just dug my heels in and  refused ...it was tantamount to rewiring the whole job again for us .  In the end they had to come back & do it . 

Exactly, it's always our problem, us that has to move kit, you have no idea how delighted I was when I got my first cordless grinder, it makes removing things so much easier. 

 

[kerching]

Plagiarism anyone?   If it is a standard axial wall fan being fitted, (i.e. where the fan body and motor basically blocks nearly half the duct area anyway), your probably not far off enough volume even with half the hole covered by the car-port support. It may not need much more cut out to still allow 100% extract rate.

Doc H.

I was suggesting an angle so that it eliminated a possible 90° bend

 

[phil d]

Thinking logically about the problem I reckon I could solve it without any patching, I'd just need a lump of plywood about 3/4 inch thick. Drill a hole in it the same size as the core, and then screw the wood to the wall, now you'd have it over the half of the hole that's visible, so using the board as a guide, with no centre bit you'd be able to drill using part of the existing hole, the flexi duct would then line up no problem, with no making good. I hope you understand what I mean, I'm much better at doing it and showing how it's done than explaining it all.lol