Green Building Forum - service voids Thu, 25 Jun 2026 04:02:23 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219113#Comment_219113 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219113#Comment_219113 Tue, 10 Feb 2015 18:57:39 +0000 djh
The major purpose as far as I know is to create a cavity inside the vapour barrier for running services, especially electrics. What I've actually found though is that it's very difficult to route electric cables:

* every batten has to be cut, chiselled, routed etc to allow the cable past

* the battens don't allow much surface to secure the cables as required by regs

* dealing with the previous problems causes frequent penetrations of the vapour barrier. My wall looked like a poor shaver's face with toilet paper stuck all over it!

What am I missing?]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219116#Comment_219116 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219116#Comment_219116 Tue, 10 Feb 2015 19:06:08 +0000 tony
I hate tf and like a batten behind the skirting if you must.]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219129#Comment_219129 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219129#Comment_219129 Tue, 10 Feb 2015 21:47:20 +0000 bot de paille
Using metal studs is less green but easier to pass services through and come with pre made holes to pass cables etc.]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219450#Comment_219450 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219450#Comment_219450 Fri, 13 Feb 2015 15:19:57 +0000 djh Posted By: bot de paillepre plan the cable run and cut the battens before fixing them, leaving a gap so you dont need to cut them after wards.
Well, yes, pre-planning would have helped. I did some of that but wasn't actually standing over them when they put the battens up!

Using metal studs is less green but easier to pass services through and come with pre made holes to pass cables etc.

Hmm, I have a couple of bits of metal stud as well, which I haven't got around to wiring yet. But as I understand it, I have to fit grommets wherever I use a pass through hole. Regs don't really let me use the holes unless there happens to be an outlet at the same height as the hole anyway, I think. The heads don't have holes so you have to cut those out! I don't understand how I clip the cables to the studs - glue clips to the studs? Drill the studs and screw the clips to the studs? Oh, and then I can't really notch a stud in the same way as a timber one if I want to put a box in front of a stud. It all seems like a lot more faff!]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219465#Comment_219465 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219465#Comment_219465 Fri, 13 Feb 2015 16:32:26 +0000 an02ew Clipping could be cable tied groups of cables that are then fixed through the tab end of tie?]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219532#Comment_219532 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219532#Comment_219532 Sat, 14 Feb 2015 17:57:05 +0000 rhamdu Posted By: djhthe battens don't allow much surface to secure the cables as required by regsAs I understand the regs, there is no absolute requirement to secure cables in a service void. In my view it's better if they are loose, should anyone bang a nail in.
In my 2011 edition (sorry I don't have the latest yet), regs 522.8.4 and 522.8.5 are relevant. Basically you must provide enough support to ensure the cables won't be damaged by their own weight, and to prevent strain on terminations. The latter requirement can often be satisfied by clipping or tying the cable firmly close to each accessory, or by glanding it to the box.]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219538#Comment_219538 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219538#Comment_219538 Sat, 14 Feb 2015 18:40:29 +0000 bot de paille service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219544#Comment_219544 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219544#Comment_219544 Sat, 14 Feb 2015 21:22:13 +0000 tony service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219557#Comment_219557 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219557#Comment_219557 Sun, 15 Feb 2015 10:11:52 +0000 markocosic
(across them in safe zone ok)]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219573#Comment_219573 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219573#Comment_219573 Sun, 15 Feb 2015 12:24:21 +0000 bot de paille
In principle even if you screw into a tubing the individual wires inside will be pushed aside. If you do damage a wire and trip the circuit breaker, a new wire can be pulled through from the outlet.]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219574#Comment_219574 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219574#Comment_219574 Sun, 15 Feb 2015 12:37:14 +0000 Mike George
Where there are socket outlets, they are generally at low level with only short cable runs (600mm max?) running through the insulated zone. such cables easily clipped to studs in timber frame; or chased in where masonry.

Copper pipe runs also in the floor void and often hidden on the surface in bathrooms and kitchens anyway. For those who really want them hidden they can still be accommodated on the internal edge of the insulated zone (though I dislike heating pipes in any insulated zone).

So why lose internal space and build in the potential for air losses from a service void? Am I missing something?]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219575#Comment_219575 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219575#Comment_219575 Sun, 15 Feb 2015 12:57:49 +0000 tony service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219591#Comment_219591 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219591#Comment_219591 Sun, 15 Feb 2015 18:24:21 +0000 djh Posted By: bot de pailleHere in france they run the cables inside a flexible plastic tube. You install the tubing first and then pull the individual earth, neutral and phase wires through them afterwards as needed. Cables reserved for exterior or low voltage.
We can use conduits in the UK as well, but it's not so usual. More emphasis on keeping initial cost down at the expense of more difficult maintenance, I suppose.

Posted By: Mike GeorgeI'm struggling to see the advantage of service voids. In most of the scenarios I've worked with, most of the services, cables and pipe runs are easily accommodated within floor voids; this having the advantage of being more easily accessible should there ever be a problem.

Most of our cabling and plumbing is in the first floor void too, and we haven't found the lack of service voids to be a problem. But then I have forbidden any services in the external walls at all! So I don't care as much about air leaks through backboxes and suchlike.

cables easily clipped to studs in timber frame; or chased in where masonry.

It does seem like the wiring regs were written by people more familiar with masonry than timber frame, though. It's all very well saying the safe zone goes up, down or sideways from the socket or switch. But if you interpret that too literally, it means you have to notch out a stud or noggin for every backbox!]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219597#Comment_219597 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219597#Comment_219597 Sun, 15 Feb 2015 20:05:27 +0000 Timber
Run battens vertically with a horizontal batten at the top and bottom. Leave a gap at the top and bottom between the ends of the vert battens and the horizontal battens.

Service voids are a great idea for air tightness and ease of service installation.]]> service voids https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219599#Comment_219599 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13093&Focus=219599#Comment_219599 Sun, 15 Feb 2015 20:51:31 +0000 Mike George Posted By: TimberService voids are a great idea for air tightness

How so?]]>