Standard Size of a GU10 LED Bulb

[toxictoad]

Hey,

I'm having all the wiring in my house redone and having lots of spotlights put in. I bought the bulbs without thinking to much about it but they were pretty cheap (£35 for 12, 7w)

The electrician fitted 5 in the loft but tried to get me to use the ones he would supply that were more expensive and had more lumens but I would rather have cheap bulbs that I can replace over time due to money restrictions and having a lot of work still to be done.

Anyhow, we've just spoken and he's told me that the bulbs I have are too deep. The bulbs are to go in the landing and bathroom and he said because they are ceiling joists not floor joists, I don't have enough clearance.

This is fair enough and could we be right. I was told that they needed to be the standard depth. I asked what this is and he didn't know, which seemed to me to be very odd.

So, I've looked at a variety of GU10 bulbs on screwfix and 50mm seems to be the most common. Is this the standard size? If not does anyone know what the standard size is?

Does anyone else think it's odd that an electrician would say they're not the standard size and then not be able to tell you what the standard size is?

Thanks

 

[PrenticeBoyofDerry]

What type/model of downlight fittings do you have?

 

[toxictoad]

I only have the bulbs. They are 72mm deep including the pins

 

[EFLImpudence]

50mm. - 2 inches - is the diameter of MR16 (16 eighths of an inch) lamps.

The depths vary.

 

[PrenticeBoyofDerry]

I only have the bulbs. They are 72mm deep including the pins

You really need to design around the depth you have in the ceiling void and the requirements of the manufacturer of the fittings regarding depth and the additional space/gap allowance.

 

[securespark]

What he said.

Imagine you have roofing felt or other material too close to the lamp (ie not enough clearance between the fitting/ lamp and the fabric of the building, this could well be a fire hazard.