Cable fishing advice please

[Jupiter01]

I have a garage conversion that has an apex roof. There is no hatch to access the roof space. This has loft insulation laid across the joists but there is an empty void above this.

I would like to install spotlights in this room. I will figure out the direction of the joists and drill some pilot holes for the spotlights and then use the "steel wire" trick to make sure that I am not striking a joist. Once happy with these measurements, I can cut out the spotlight holes.

I have a set of cable fishing rods and wanted some advice and tips on how I fish them through given the rockwool insulation that will need to be penetrated. My holes are likely to be around 1.3 metres apart.

The room currently has two pendants in the centre. I will wago these and box them up as they will need to be maintenance free and extend the cable to the first spotlight.

Any suggestions will be gratefully received.

 

[Jupiter01]

Good morning, can I please ask for any advice re. the above please. Im sure you seasoned pros have done this many times.

Thanks again.

 

[Taylortwocities]

Very shortly. The insulation is there to keep the room warm. If you dig holes in the insulation then you will lose heat.
And heat costs ££££
Also any moisture will be drawn up from the room into the cold area above the insulation. There it will condense causing damp.

If you had wanted downlights the roof should have been a warm roof construction where the void is below the insulation, not on top.

Untitled

• Taylortwocities
• 20 Apr 2015
• 1
• cold roof warm roof

Can’t help on how to use the cable rods. Any void is full of road blocks. It’s a matter of suck it and see.

Better not to start.

 

[SUNRAY]

Even better advice would be to use fittings which give a better/usable light rather than silly things where one has to dodge around the room to find appropriate illumination for the task in hand.

 

[Jackrae]

In answer to your question : In the first light hole push a fish rod through the insulation with a length of cord tied to the end and drive the rod at as shallow an angle as possible towards the location of the second light hole. At the second hole push a rod, fitted with a hook-end through the insulation and angle it towards the first hole. Then work the second rod to try and catch the cord attached to the first rod. This cord then acts as your cable pull.
No doubt the professionals will poo-poo this but .....
Or, alternatively cut an inspection hatch big enough to provide required access, cut out that section of insulation, install wires to desired locations then replace cut-out section with insulation on top and fit suitable trim to cover cuts.

 

[Taylortwocities]

Poo poo

 

[davelx]

But don't poo poo the poo poo!
cf. General Melchett

 

[FrodoOne]

I have a garage conversion that has an apex roof. There is no hatch to access the roof space. This has loft insulation laid across the joists but there is an empty void above this.
Any suggestions will be gratefully received.

You have a "a garage conversion"- with "an empty void" above but no "access".

Why not make "access" by installing a "manhole hatch" somewhere (appropriate) in the ceiling?
(i.e. Between two joists.)

In my opinion, any "roof space void" should have "access".

I had a vaguely similar situation in a house where the only "manhole hatch" access was over the "walk-in wardrobe" - meaning that dust etc. would be brought down into that area whenever access to the Roof Space was required.
At the other end of the house under the same roof was an attached garage with no Roof Access.
The "solution" was to cut a new "manhole hatch" access in the garage ceiling, with a hinged "cover" with "cement sheet" cladding - to make it relatively "fire-resistant" - which is not a particular consideration in your case

 

[Taylortwocities]

You have a "a garage conversion"- with "an empty void" above but no "access".

I think you misunderstand. The garage has a pitched roof. I guess that celotex has been stuffed between the joists and plasterboarded over.

So no practical way of accessing any void which, I assume is between the top of the celotext and the roof tiles.

@Jupiter01 actually, removing the ridge tiles and doing the wiring from outside might be your option. Better not to do it at all.

 

[Jackrae]

He mentioned "rockwool insulation", which could be anything. So best option is probably what was mentioned in #5 and #8 cut manhole access

 

[Taylortwocities]

As the roof joists run down from ridge to wall plate, where EXACTLY do you expect him to cut this manhole access??
The joist set up means he would need an access somewhere on every joist run.

 

[Jupiter01]

I think you misunderstand. The garage has a pitched roof. I guess that celotex has been stuffed between the joists and plasterboarded over.

So no practical way of accessing any void which, I assume is between the top of the celotext and the roof tiles.

@Jupiter01 actually, removing the ridge tiles and doing the wiring from outside might be your option. Better not to do it at all.

I have rockwool type insulation laid on top of the joists. Not cellotex. I am hoping that the fishing rods will pierce through this and allow me to loop cables through the holes for the spotlights

 

[Jupiter01]

As the roof joists run down from ridge to wall plate, where EXACTLY do you expect him to cut this manhole access??
The joist set up means he would need an access somewhere on every joist run.

I have trusses in the roof. I could cut a manhole in between joists but it will be an eye sore on this otherwise plain ceiling. I could do one temporarily and then fill it up once the lighting is done. Will consider that if the cable fishing suggestion above does not work.

 

[FrodoOne]

actually, removing the ridge tiles and doing the wiring from outside might be your option.

Since it was a garage it would be single story only.

If it is a Marseilles Pattern (or similar) tile roof, it would be possible to remove the "edge" tiles (rather than the "ridge" tiles) to get down between outside walls and
removing four tiles (plus cutting one bittern - and, later, replacing it) should allow access to the ceiling space proper.

 

[Why Not Indeed]

I could cut a manhole in between joists but it will be an eye sore on this otherwise plain ceiling

You're worried what your garage ceiling looks like? Really? Even in not-garages, access hatches in the ceiling aren't exactly unusual.