I mainly use twin 13 Amp sockets for everything. My van stock of singles is generally used for replacement of faulty single sockets only. I am generally too lazy to do chasing these days, so it is surface work or a very big bill at the end. Years ago a single socket at the top of the stairs in a small modern house was only used for a vacuum cleaner as there was no room for a small table and table lamp. New 1970s houses often had only two single 13 Amp sockets in bedrooms. How did people cope?


Z.

Back in the 1960’s the local council Rating Officer surveyed houses and flats to determine the Rateable Value of the property’s and the tax the occupiers had to pay to the council.


There was a notional basic standard, anything extra was considered luxury items and increased the Rateable Value.


For example more than two rows of six inch tiles around the bath was considered a luxury and increased the tax that had to be paid by those who lived in the houses.


More than one single socket in bedrooms was a luxury as was additional sockets in kitchens and living rooms, I live in a road with 1960’s three and four bedroom houses, however when they were built the four bed houses they were actually sold as three bedroom houses with a box room that did not have a plug socket in the box room or on the landing. Quite a few of these houses still only have three single sockets upstairs with a small bedroom that does not have a plug socket.


 Generally I cannot imagine anyone would install a single socket these days, but back in the 1960’s the reverse was true as no one wanted the additional tax burden of having additional sockets.


The outcome was lots of DIY home improvements in the 1970’s and 80’s to improve the houses without telling the tax man, then Maggie introduced the Poll Tax, we had a few riots and it was changed to the Council Tax and estate agents were paid to drive along roads valuing houses without getting out of their cars and definitely without counting plug sockets.


Some politicians want to go back yo the old system and value homes individually with a council official going to every home to work out the tax bill, others want a general review of the bands that homes are currently in because there are now so many anomalies.


If USB sockets and LED down lights are counted individually to calculate the tax bills some people will go into meltdown ?


Andy Betteridge

Single sockets?

Handy for kitchen appliances when fed from 20A dp switches above w/top height - prevent more than one item being plugged into the same socket such as a washing m/c and spin dryer.

Handy for a 2A clock socket or 5A socket to feed items such as under-cupboard lights, also makes such items easy to isolate by the customer when fault finding.

Although permitted, I don't like 13A sockets supplied in 1.5mm cable. How feasible is it that a satisfactory Zs can be achieved every time by using such?

Nearly always doubles for me -  normally the only exception is where the bit of wall is too narrow for a double (or occasionally where a triple would be better).

   - Andy.

Triple sockets are an oddity as they have a built in fuse holder and are fused at 13-amps, so can be installed to replace a single socket when you should not install a new double socket next to an existing single on a spur.


Andy Betteridge

"when you should not install a new double socket next to an existing single on a spur "

Not sure I follow

For general use in a home or business, I would almost always install twin 13 amp sockets, they cost no more in labour or materials and in most circumstances are the default choice.

Exceptions include.

On a generator or UPS supply when it is desired to limit the loading.

When space only permits of a single.

When controlled by a remote switch, such as for under counter kitchen appliances.

For a single specific load, such as a water cooler or a vending machine in a public place, when it is desired to deter other uses.

When required by the client, to make provision for charging an electric wheelchair. (some obscure regulation ALLEGEDLY prohibits use of a twin socket this purpose. I doubt the existence of this regulation, but best to play it safe when dealing with the disability industry)


If BS 543 outlets are needed, these are virtually certain to be single as twin versions are not widely available. 

Ahh right I see. a spur

I was thinking of an existing single on say a riing not being used to supply a twin as a spur. Wheras a twin or single on a ring could feed a twin or single as.

Obviously I misunderstood your point Andy

I agree that there is little advantage in installing a single where a double will fit, but they are appropriate for a single kitchen appliance in a niche, or where a double will not fit.


As for rateable value, there is no mention of sockets when my house was surveyed for that purpose in 1929.