Fire rated downlights and building regs

I was always under the impression that a typical 2 storey house had no fire compartments.  They aren't required to have fire doors at the top or bottom of the stairs.  In which case, fire coming up through the floors is the least of your worries if downstairs is on fire and you're upstairs.

Once you go to 3 storeys, including loft conversions, then fire regulations are more strict.

Building Regulations here in NI require the first floor in a 2 storey dwelling house to have an REI of 30mins. R being load bearing capacity, E integrity and I insulation in accordance with a European classification. popping in fire-rated downlights is unlikely to be questioned on the domestic side but one must remember that fire resistance of elements of structure should be tested as a composite. 

Don’t get advice from wholesalers, follow this advice in the link and watch out for NHBC on new builds as they only permit certain downlighters on eco joists.

Also that video is 5 years old now, there’s plenty of good robust downlighters available now that are fire rated and are ok to be covered with insulation. 

However, there are some aluminium lamps that direct heat through the lens of the lamp and so need a smaller pocket of insulation to safely accommodate the fitting. Unfortunately there is no way of ensuring that bulbs are not interchanged and so cause potential future heat build-up problems if changed from one type to the other.

I thought that Dichroic lamps (the 230V versions at least) has  GZ10 cap rather than a GU10 - the difference being the lack of a chamfer around the plastic base - so should only fit into holders that are intended to accept them.

  - Andy.

Colin Haggett: 
 

Also that video is 5 years old now, there’s plenty of good robust downlighters available now that are fire rated and are ok to be covered with insulation. 

Thanks. 

I‘m aware of insulation contact products, however this is separate to the fire rating integrity. 

The video from JW suggests that for buildings of 2 levels (ground and first floor), creates a single fire compartment (unless you have a garage). 

The general “trend” and belief if you like between contractors is to install FRDs in ceilings on the ground floor, but it appears (according to JW) this isn’t required by regulation? 

AJJewsbury: 
 

However, there are some aluminium lamps that direct heat through the lens of the lamp and so need a smaller pocket of insulation to safely accommodate the fitting. Unfortunately there is no way of ensuring that bulbs are not interchanged and so cause potential future heat build-up problems if changed from one type to the other.

I thought that Dichroic lamps (the 230V versions at least) has  GZ10 cap rather than a GU10 - the difference being the lack of a chamfer around the plastic base - so should only fit into holders that are intended to accept them.

  - Andy.

This is correct, one is 230v the other 12v. 

You can however very easily swap the lamp holder by removing the transformer, maybe this is what they mean (as in, it’s very easy to change the lamp holder type). 

Looks like AD B (dwelling) only requires 30min R For 2-storey houses. The E and I are not requirements as they are here in NI.

 We are rarely involved in domestic projects. On the commercial side BC officers often request evidence to demonstrate that elements of structure are appropriately fire-protected. So, for example, in a recent hotel refurbishment, the ceilings were required to be 90min REI. The ceilings were installed to British Gypsums White Book. For whatever reason, the electrical contractor installed downlights directly in that ceiling where, in fact, there should have been another ceiling below to accommodate such penetrations. 
Even though the downlights were 90min, the assembly was rejected as there was no test data to support any claim that the floor above was adequately protecte.

Indeed when the downlights were removed, it wasn’t a simple matter of repairing the ceilings. Large areas of plasterboard had to be removed before the repair was deemed appropriate.

This applied to 40 rooms!