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FatAlan

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In the day and age of ..how many downlights can we get into one house, I'm intrigued to know what tricks / techniques folks use to install multiple downlights into an existing ceiling in replacement of a central pendant. In particular, once having located the joists, how do you get the cables across or through the joists with minimal damage to the ceiling? Is it a case of just cutting an access hole in the ceiling across the bottom of the joist so that you can see both sides with enough space to drill a hole (building regs compliant). Does anyone cut small notches and protect with steel plates for instance?
 
With you dusty, if I can’t get the floors above up them it’s cut neat round holes (sharp holesaw) and timber across and reinstate the cutouts, bit of fine filler and all’s good :)

Edit.....unless it’s artex then it ain’t getting done..
 
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Do the job properly,

joking apart what access do you have from above, how many lights, in what direction are the joists layed out in etc etc?

Getting across ceiling joists from below - tricks of the trade. Screen Shot 2017-08-05 at 12.23.18 - EletriciansForums.net
 
New builds nearly always cut holes in ceiling and drill through joists them patch back in with batten and the plasterboard that has been cut .

Notching underneath joists is not permitted .
 
I always say “you gotta break eggs to make an omelette” - once I’ve explained this 3 or 4 times they let me holesaw loads of holes (I use 100mm so I can get my arm in there) to drill your joists.
It’s the careful planning of where the joists are so you can do as few holes as possible to route your cables.
It’s music to my ears when they state that the ceiling will be skimmed!
 
With you dusty, if I can’t get the floors above up them it’s cut neat round holes (sharp holesaw) and timber across and reinstate the cutouts, bit of fine filler and all’s good :)

Edit.....unless it’s artex then it ain’t getting done..


Artex is horrible to repair

I just done a small job a kitchen where the electrical job took about 25 mins after cutting a small hatch in the ceiling

The making good and applying a fresh splodge of artex to the new bit of boardi put in took about 3.5 hours in an attempt to make it look like the ceiling hadn’t been cut
 
Does anyone cut small notches and protect with steel plates for instance?

I'm pretty sure the building regs say that you can only put a notch in the top side of a joist, not the bottom, in the region that is between 0.07 and 0.25 of the span. Electrical regs then require you to protect the cables against penetration. Better to route your cables in the zone where you can drill holes through the joists.
 
I did the whole thing, even a complete narrow section of plasterboard down, then reinstate the board. I’d always have the customer pay to have it plastered & decorated afterwards, unless it was only a couple.
 
Drill 100mm holes between joists, with a sharp hole cutter, about 3inches from one side of the joist, if you can

Use a 400mm long wood spade bit to drill through joists at appropriate height (ALWAYS check the other side of the joist before you drill through for pipes and cables)

Cut up 8in lengths of 1x2in roof batten(keep an eye out in builders skips they usually discard loads of off cuts), or the bits that come in oven packaging!
keep it in your van always

Use drywall screws to fix batten across holes and fix your circular cut out back in hole after wiring(paying attention to which way round they go and what one went it what hole, this is important for the best making good job)

Buy a bag of easi-fill and get some decent making good tools and fill holes
I personally use a little squirty water bottle to wet the area first and prevents your filler from drying out, but generally even a child can make a good job with this stuff its excellent!

Job done!
 
Drill 100mm holes between joists, with a sharp hole cutter, about 3inches from one side of the joist, if you can

Use a 400mm long wood spade bit to drill through joists at appropriate height (ALWAYS check the other side of the joist before you drill through for pipes and cables)

Cut up 8in lengths of 1x2in roof batten(keep an eye out in builders skips they usually discard loads of off cuts), or the bits that come in oven packaging!
keep it in your van always

Use drywall screws to fix batten across holes and fix your circular cut out back in hole after wiring(paying attention to which way round they go and what one went it what hole, this is important for the best making good job)

Buy a bag of easi-fill and get some decent making good tools and fill holes
I personally use a little squirty water bottle to wet the area first and prevents your filler from drying out, but generally even a child can make a good job with this stuff its excellent!

Job done!
 
Lost count of number of customers in new builds who in the rush to move in decide to lay expensive carpet and decorate. Then call a electrician to fit downlights if only they waited a week or so.
The one that annoys me is when you feed a cable between two parallel joists and find theres a timber going between them!
I am a fan of the hole being made.good with a timber and use the disc method.
Did just that last week in a new apartment, the ceiling and walls are all metal stud work so easy to find but due to amount of insulation and the sprinkler system being in the gap, had to cut holes to move lights.
Customer will be getting it sorted by decorators afterwords.
 
Drill 100mm holes between joists, with a sharp hole cutter, about 3inches from one side of the joist, if you can

Use a 400mm long wood spade bit to drill through joists at appropriate height (ALWAYS check the other side of the joist before you drill through for pipes and cables)

Cut up 8in lengths of 1x2in roof batten(keep an eye out in builders skips they usually discard loads of off cuts), or the bits that come in oven packaging!
keep it in your van always

Use drywall screws to fix batten across holes and fix your circular cut out back in hole after wiring(paying attention to which way round they go and what one went it what hole, this is important for the best making good job)

Buy a bag of easi-fill and get some decent making good tools and fill holes
I personally use a little squirty water bottle to wet the area first and prevents your filler from drying out, but generally even a child can make a good job with this stuff its excellent!

Job done!
Good tips there. If you are drilling from one side of the joist through a 100mm hole how can you check to see if there’s anything on the other side without check via an access hole? Is that what you mean by 100mm holes between all joists that you’re routing between? :cool:
 

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