Cables through the roof

[Jake Royd]

I'm about to fit solar panels to the roof of my MH.
I'm familiar with the system I will fit having had a boat for many years with a similar set of parts.

However, the cables for the panels will of course have to go through the roof and into a cupboard etc. inside. I will use an external cable gland.

My concern is the construction of a typical roof?
What layers are there and how thick is it?
I have not removed any interior finishers yet to have a look.

The MH is a Chausson Welcome 85 , 2008 vintage.

TIA

 

[Stealaway]

Mine is about 20mm. I would drill up from the inside to sure you are where you want to be in the cupboards.

 

[138go]

Roof construction varies depending on manufacturer. Ours has cloth covering with foam then a hard surface followed by an insulating layer then gps roof.

I would drill a 1mm hole from the inside first and make sure where it comes out. If you use one of the standard type roof outlets you then have the opportunity to move it slightly before you drill the larger hole for the cable. You can then glue The roof outlet into position using something like Sikaflex adhesive.

Fit a double one while you are about it you never know you might need it in the future

 

[scotjimland]

In addition to using the gland box,

after pushing cable through the hole, fill hole up with Sika or silicon adhesive.. pump it in around the cable until it oozes out the other side.. .. then glue down the gland box.

This will not only guarantee a watertight roof, but act as a grommet and prevent any possible chaffing of the cable on the sharp edge of the hole.

 

[Mikeco]

I once drilled a 20mm diameter hole in a Chausson roof and cut a cable in half. As mentioned drill a small hole first and work up to the size you need. You could test for cables first if you have a tester.

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[Jake Royd]

Good advice everybody, thank you.

 

[pappajohn]

Roof construction varies depending on manufacturer. Ours has cloth covering with foam then a hard surface followed by an insulating layer then gps roof.

I would drill a 1mm hole from the inside first and make sure where it comes out. If you use one of the standard type roof outlets you then have the opportunity to move it slightly before you drill the larger hole for the cable. You can then glue The roof outlet into position using something like Sikaflex adhesive.

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Fit a double one while you are about it you never know you might need it in the future

Fitting solar panels requires a double anyway, one gland for each cable.
Never put both cables through one gland, it will never be 100% waterproof due to the figure 8 shape.

 

[Phantomphixer]

Depending on the roof construction I would try and use a cable detector first to check there is nothing running through the roof layers at that point. I also use a magnet tester (used to detect magnetic field of solenoids) and place a strong magnet on the roof to pinpoint on the inside where your expecting the hole to be. Manufacturers run all sorts of cabling in the roof layers in some vans. Better get it right first time than pepper your roof in unwanted holes.

 

[Jake Royd]

Good point.