Replaced an outside light, what is best to seal it with?
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In the main best not to seal it, but have a drain hole. If the lamp seal fails as it warms up and cools down it can suck in water, even a hole which seems in a place which should not get wet, capillary action can result in water getting there, so in the main better if the lamp is allowed to breathe.
Clearly a problem if the globe is glass, if plastic then drill a hole in the bottom, I find petroleum jelly works well, but sealing may result in the reverse to what is wanted. I have filled junction boxes with petroleum jelly if no room for air, it can't draw in water, and petroleum jelly is re-enter-able.
Clearly a problem if the globe is glass, if plastic then drill a hole in the bottom, I find petroleum jelly works well, but sealing may result in the reverse to what is wanted. I have filled junction boxes with petroleum jelly if no room for air, it can't draw in water, and petroleum jelly is re-enter-able.
If you need to seal round the cable entry, you can use waterproof compound - which no doubt will come in handy for other outdoor jobs as the years go by.
Read the manufacturer's instructions.
It's all there.
Some fittings require a bead of silicone between the bricks and 2 grooves at the back of it.
Some others have spongy washers.
All of them I fitted have weeping holes somewhere at the bottom.
Manufacturer might know best, not always, but often.
It's all there.
Some fittings require a bead of silicone between the bricks and 2 grooves at the back of it.
Some others have spongy washers.
All of them I fitted have weeping holes somewhere at the bottom.
Manufacturer might know best, not always, but often.
No it won’t. It might stop a draught for a short while, but not water. Blue-tak starts off solid and becomes pliable if you work it.
Left outside in sun and frost it will harden.
Silicone sealant is the kiddie.
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I know I'm an old fuddy-duddy but I used to use R 39 sealing compound. Don't know if it's still around though.
Surprisingly nothing on the paperwork supplied relating to dealing to the wall. All it mentions is about wrapping insulation tape twice around the cable connectors.
Is it good practice to leave without any seal or gasket?
It’s not good practice. You need to seal the box to thd wall and seal the cable entry. Also (if there isn’t one) drill a 6mm drain hole in the bottom.
If you don’t do these things then your connection box will fill with water, and pop!
And using insulation tape round connectors is bad practice. The box itself is the containment. Sticky tape adds nothing but sticky.
Where on earth did you buy this thing?
Do you have a link to the product?
If you don’t do these things then your connection box will fill with water, and pop!
And using insulation tape round connectors is bad practice. The box itself is the containment. Sticky tape adds nothing but sticky.
Where on earth did you buy this thing?
Do you have a link to the product?
R391? Still around and also quite a few other makes of very similar compound, I dont know if BICC had a patent that expired at some point or similar.
Always ask for it as "Dog s**** compound"
Typical incorrect manufactures instructions that you can ignore. So called insulation tape is crap that dries off over the years and leaves a mess.
Seal around the top and sides with silicon sealant and leave the bottom so any condensation can run out.
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Yes! R 391. Knew R39 was familiar but didn't sound quite right...
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Mmm, maybe.
Memory failing you, SS? What’s it like up in an airship?