fitting flush mounted CU

[Martin Carroll]

Anyone have any experience of installing a flush mounted CU?

I am about to start the wiring on the renovation project and have gone
for a flush mounted CU. The CU is in the downstairs cloaks and as it
has to be at an easily accessible height (<1200mm) I decided a standard
CU would look a little clumsy.

The wall it will fit on(in) is the inner (blockwork) leaf of the
extension and has the meter cupboard on the outside wall.

I had thought that I would remove one of the (lightweight) blocks and
fix the new CU into the gap. However all the cable entry points are
set back a couple of cms or so from the front of the case and I cannot
see how the cables will get into the consumer unit easily (at least
without having to remove more of the blockwork above the CU, and this
seems a little dodgy to me).

One option I am exploring is to dry line the wall where the CU sits and
make the batten size sufficient as to have the cable entry holes proud
of the rest of the wall. This has the added advantage of providing
plenty of space for the cables to run behind the plasterboard and on to
the rest of the house. The only disadvantage of this I guess is the
loss of a small amount of space in the room.

Any thoughts are welcome.

Cheers

Martin

 

[BigWallop]

Anyone have any experience of installing a flush mounted CU?

I am about to start the wiring on the renovation project and have gone
for a flush mounted CU. The CU is in the downstairs cloaks and as it
has to be at an easily accessible height (<1200mm) I decided a standard
CU would look a little clumsy.

The wall it will fit on(in) is the inner (blockwork) leaf of the
extension and has the meter cupboard on the outside wall.

I had thought that I would remove one of the (lightweight) blocks and
fix the new CU into the gap. However all the cable entry points are
set back a couple of cms or so from the front of the case and I cannot
see how the cables will get into the consumer unit easily (at least
without having to remove more of the blockwork above the CU, and this
seems a little dodgy to me).

One option I am exploring is to dry line the wall where the CU sits and
make the batten size sufficient as to have the cable entry holes proud
of the rest of the wall. This has the added advantage of providing
plenty of space for the cables to run behind the plasterboard and on to
the rest of the house. The only disadvantage of this I guess is the
loss of a small amount of space in the room.

Any thoughts are welcome.

Cheers

Martin

Or make the cable rear entry into the CU. Drill and cut, or use the rear
knock-outs, where you want the cables to enter. You can then use the one
block idea to fix the consumer unit.

 

[Martin Carroll]

Or make the cable rear entry into the CU. Drill and cut, or use the rear
knock-outs, where you want the cables to enter. You can then use the one
block idea to fix the consumer unit.

That would mean getting cables into the cavity though!

Cheers

Martin

 

[BigWallop]

That would mean getting cables into the cavity though!

Cheers
Martin

Even if you push the cabling over, under, to the sides of the consumer unit,
where the space is, in the surrounding blocks? How many fixings are holding
the CU? One at either side, near the top, and two through the bottom into
the blocks. You don't need any across the top. Leave the top as free space
to accept you cabling.

Just another little thought.

 

[Andy Wade]

I had thought that I would remove one of the (lightweight) blocks and
fix the new CU into the gap. However all the cable entry points are
set back a couple of cms or so from the front of the case and I cannot
see how the cables will get into the consumer unit easily (at least
without having to remove more of the blockwork above the CU, and this
seems a little dodgy to me).

I may be missing something obvious, but why can't the cables run in
vertical chases in the blockwork above and below the CU (using oval
conduit or capping)? You'd be cutting away some of the blockwork above,
but only relatively shallow chases. If it's to be plastered you can run
on the surface under capping and only chase the last few inches in to
the depth required to meet the knockouts.

Getting the tails in is usually more of a challenge since they won't be
RCD protected and need to be more than 50 mm deep from the surface.
There does seem to be some acceptance of running them in the cavity, but
you do need to consider the thermal insulation derating.

 

[Martin Carroll]

I may be missing something obvious, but why can't the cables run in
vertical chases in the blockwork above and below the CU (using oval
conduit or capping)? You'd be cutting away some of the blockwork above,
but only relatively shallow chases. If it's to be plastered you can run
on the surface under capping and only chase the last few inches in to
the depth required to meet the knockouts.

Certainly a possibility I will explore.

Getting the tails in is usually more of a challenge since they won't be
RCD protected and need to be more than 50 mm deep from the surface.
There does seem to be some acceptance of running them in the cavity, but
you do need to consider the thermal insulation derating.

I can probably run them into the back of the CU as the meter cupboard is
directly opposite on the outside wall.

Cheers

Martin