Fire rated back box advice

[Mikey W]

Hi all,
I was wondering what some of you recommend with regards fire rated back boxes.
this is an install in my own home and want the best option available (cost not been an issue)
scenario : timber frame house semi detatched and currently no outlets on party wall (double boarded) I will be rewiring shortly and installing outlets on the party walls any advice on the best boxes to use?

many Tia Mike

 

[snowhead]

Maybe there's a clue with there not being any outlets there from new.

The above may help, from a timber frame manufacturer;
http://www.fforest.co.uk/files/Fforest Std details.pdf

See Also;
Switch Box Inserts - 2 Hour Fire Rated / Energy Saving - TENMAT - https://www.tenmat.com/passive-fire-protection/electrical-service-penetrations/switch-box-inserts/

 

[Mikey W]

hanks for the reply but not really an answer to my question I understand the procedure of fire rating and have worked on many new builds in which we would protect against fire via the method on your attached picture,but this is already constructed hence not taking that route.
also the reason there's non from new is that one there aren't many outlets for one and this would have meant unnecessary extra work and time at the time of install incurred extra cost etc.
I was simply asking who has used the different types and what would they recommend as the best in overall fitment qaulity etc.

 

[Silly Sausage]

Box liners appear to be a way to go:
Astroflame Fire and Acoustic Socket Box Insert - £2.99 ex VAT - https://www.safelincs.co.uk/astroflame-fire-and-acoustic-socket-box-insert/?fGB=true&gclid=Cj0KCQiAxZPgBRCmARIsAOrTHSawQRNSSVgk_u5OqPGHN03mHJziHDVHrjydp7gjRMyyng9p1SIrBskaAm1REALw_wcB

or ...

2 Gang 35mm Fire & Acoustic Metal Dry Lining Plasterboard Box - https://www.tlc-direct.co.uk/Products/FB4235.html?source=adwords&ad_position=&ad_id=315107931576&placement=&kw=&network=u&matchtype=&ad_type=&product_id=FB4235&product_partition_id=297072075353&version=finalurl_v3&gclid=Cj0KCQiAxZPgBRCmARIsAOrTHSYx7tDdtxGoPAdxYAA96Zn1UwqkLqs63gYB0mc6oI7VfJqndshZDuYaAvy-EALw_wcB

Never heard or used of them before, maybe worth checking out.

http://www.nhbc.co.uk/Builders/Prod...uidanceDocuments/81/filedownload,71729,en.pdf

 

[Mikey W]

Archy thanks for the reply particularly the guidance note from nhbc I have something similar in the depths of my document files.
And yeah the liners I think are the way forward I'm going to hold of a few different types to see which are best.
Fire protection is way too often overlooked but is a very important part of installing.
in my experience as a sparky I have seen so many installs that do not adhere to fire protection at all which is quite worrying.

 

[Strima]

I’ve used the boxes from TLC and there feel to be decent quality.

Only downside I’ve found the can be difficult to install in double board due to the layout of the tangs on the sides.

 

[Wilko]

Hi Mike - if I've understood correctly you're thinking to treat the party wall like a normal partition wall, plus a fire rated box? Of course I could be wrong, but I think your cables shouldn't be in that void without permission (?) - as it's a party wall. If so, you might need a false wall, which is in effect what the top diagram is doing, keeping all your stuff in your wall.

 

[Toneyz]

I would batten the wall out with thin wooden or metal batten as it is an existing wall.

 

[Deleted member 26818]

You can get intumescent sheets, which you then cut to size and squish into the back box.
It’s a bit like sheets of plastecene.

 

[Mikey W]

Thankyou Strima and yes I see what you say about the tabs.

Hi Mike - if I've understood correctly you're thinking to treat the party wall like a normal partition wall, plus a fire rated box? Of course I could be wrong, but I think your cables shouldn't be in that void without permission (?) - as it's a party wall. If so, you might need a false wall, which is in effect what the top diagram is doing, keeping all your stuff in your wall.

it's actually a party wall but the actual cavity is shared by both houses and cables can be run in that wall. there are properties on the estate dependant on orientation have outlets on and cables run in.

I would batten the wall out with thin wooden or metal batten as it is an existing wall.

just sat here looking at the wall and that exact thought plus it's an additional acoustic defence and I don't have to mess around getting cables in that void sounds like the best option.

Thankyou all for all the input!!!