When and where to retro fit fire clips if at all

I follow the late Michel Roux to the letter, but generally feel free to modify recipes.

The point is that a guide is never more than an expert opinion, even a committee of experts. It may be persuasive in a court, but you still need your expert witness(es).

But, none the less the  use of advice in a guide or standard, without the application  of any associated thought, does not guarantee a good job, nor does in confer immunity from all liability.
By all means refer to the advice, but part of that process is to understand when it does (and also does not) apply. There is an important difference between BS7671 and a cookery book.

Mike

The relevant regulation was introduced in BS 7671:2011+A3:2015 (IET Wiring Regulations Seventeenth Edition), which was published In January 2015 and came into effect on 1 July 2015.

It is now ten years since fire clips in escape routes became a BS7671 requirement, at that time I was preparing EICRs for a housing association contractor with instructions to carry out repairs and upgrades as required when preparing an EICR as part of void maintenance, so the housing association always received a satisfactory EICR, allowing them to move new tenants in immediately, as is common practice.

When the housing association houses and flats I worked in were built they had electric ducted warm air heating from a central unit, these had been  replaced with storage heaters supplied using cables in plastic minitrunking run along the tops of the walls over doorways, including the front doors.

I have just checked my emails and I had this discussion about fire clips with the HA contractor ten years ago and started retrofitting the fire clips during void maintenance immediately, in September 2015 the housing association asked the question should the lack of fire clips be a C2 or C3 for cables run in plastic trunking within the houses and flats, after a discussion it was agreed that it would be a C2 and we continued to install the fire clips.

electrical.theiet.org/.../escape-routes.pdf

I concur

The phrase “only a guide” would relate to many documents including BS7671, however Electricity at Work Regulations 4,6 and potentially others would be applicable. Guidance serves as a way to comply with law and should be treated as such. Best Practices Guides are industry standard guidance and a consensus of experts and recognised in legal cases, therefore would be the applicable information to help comply. Without guidance, the industry would be a Wild West of people’s uncoordinated opinion. 

for retrofit over odd shaped trunking etc. 
https://www.tlc-direct.co.uk/Products/FXBAND12W.html

No need to paint this builders band, it is already made painted white like that.
A bit of practice with tin snips and bending it round a bit of wood the right size means you can prefabricate a few top hat shapes while at ground level, then when installed they all look the same size and profile.
A pair of white screw caps either side complete the look.
https://www.screwfix.com/p/essentials-6-8ga-100-pack-white-polypropylene-screw-caps/88327

The fact that the cap softens in a fire, like the trunking it holds up, is not a structural matter so long as the screw head will not pass through the holes in the band.  Been seeing this sort of thing for quite a while now...

Mike

Hi Chris you raise a good point around the brittle trunking, maybe we need to replace it any way.

I am surprised that there aren't products on the market than can't be retrofitted over trunking

I have in a couple of situations, used BuildersBand (spray painted white) to put around existing 50x50 trunking. IMO it's preferable to have metal supports outside the trunking when it contains unsheathed singles, as then you're not by-passing the insulating properties of the trunking itself. Having only basic insulation between live conductors and the clips, which are then in contact via the screws with whatever the substrate might be - in these days of foil backed plasterboard, resilient bar and steel studs etc. isn't really in the spirit of chapter 41.

As for plastic wall plugs, I reckon they're OK if the screw would likely stay in place if only gravity was pulling on it and the plug had been omitted - e.g. a horizontal hole (in a wall say) and a decent length of screw I reckon it would normally be fine. Underneath a ceiling, I'd have my doubts.

   - Andy.

Daniel S Robinson said:

Following the release of the new best practice guide 4 in March 2025, I see the C3 option has been removed for cables not supported against premature collapse, now there is only a C2 option.

It is only a guide.

Daniel S Robinson said:

but some of the trunking is that old and brittle it would break if you remove the lid.

So past its sell-by date in any event.

I am surprised that there aren't products on the market than can't be retrofitted over trunking without having to remove the lid. I know not suitable for all situations but very useful in areas where it doesn't matter too much what it looks like such as industrial areas or corridors and passages. 

Gary