What should an electrical circuit / layout design drawing look like? Any examples?

[Great_scot_selfbuild]

I'm looking to make sure we document our electrical design and detail of all the layout. I have a very useable and functional method I'm using at the moment, but would like to know what it 'should' look like. We have a principal designer and this detail is exactly what I expect to be provided, but I'll be honest - on some of the nitty gritty drawing detail like this, I think it may fall short of expectations. Hence, I'm interested in:

 

1. Is there a layout / standard style that an architect would produce (to be clear, our PD isn't an architect - we couldn't afford to use our architect from planning phase for the construction drawings).

2. Are there other methods that anyone has found to be preferable / useful / look good.

 

Thanks

[ProDave]

When I have been wiring a new house for the client, the first thing I do is go round with a tape measure, a big black marker pen and put a cross on the wall where all the sockets etc will be according to whatever drawings I have been provided with.

 

Then I walk round with the client and discuss their needs, wants and preferences.

 

Invariable most of the socket positions get changed as do lighting positions.

 

As to kitchens. I have yet to see a new house built with the kitchen layout shown on the plans, another thing that gets changes as things evolve so don't even start the wiring for that until the kitchen is on order.

 

What I am saying is don't get over excited about drawing plans.  Unless you are the unusual client where nothing changes when you see the building for real.

[Bramco]

Agree entirely - I could send ours through but everything changed - well not quite but a lot did, re position of lights and switches. Like @ProDave says, we went round with the contractor marking up the final position of switches sockets etc. Quite a lot stayed the same though, but this was mainly things like the position of the switches and controllers for the rooflights and external blinds and the kitchen electrics.

 

You do need something though to get trades to quote from. I wouldn't think that changes in position of switches, light fittings etc. should matter but adding or deleting them should increase/decrease the bill.  An electrician would need to know about appliances (ratings) and where they will be, so kitchen, as well as things like ASHP and MVHR. They need to spec a big enough CU with components.

 

Use your floor plan and mark the expected position of switches, light fittings and sockets and get the specs for all the equipment like MVHR, ASHP, etc. and also the kitchen appliances.

[joth]

7 hours ago, Great_scot_selfbuild said:

I'm looking to make sure we document our electrical design and detail of all the layout.

One question is your priority documenting if for quotation, construction, or post-completion maintenance purposes?

 

My experience so far is:

- For quotation a comprehensive schedule (Google Sheet) of fittings (type, room, wiring required) is sufficient, and indeed preferable to detailed drawings for the reason Dave lists.

- For construction, drawings with plans and where relevant elevation show location of each fitting is necessary, but often sockets and lights gets moved about during 1st and even 2nd fix.

- For maintenance, ideally one would also have drawings showing the hidden pipework and wire routing. Realistically this would HAVE to be done after 1st fix (but before walls closed) because I've never yet met a trade that will actually follow plans: often times unforeseen practicalities means they can't, but in all cases they will have their own habits and preference and just do it the way they think it should be done rather than how any plan says it is to be done. And in practice I've yet to see anyone actually create such plans: there's too much rush to get started on boarding. These days your best bet is some comprehensive photos (360degree camera is ideal) of every surface of every room.

 

The exception to all the above is if you're literally doing it all yourself in which case you can control a lot more! 

[Spinny]

Extract from a tender drawing attached. Not sure where the list of symbols comes from.

We marked up a drawing ourselves with what we thought we wanted having been told there would need to be an electrical plan to quote against. Our architect, and I guess many, did not offer any kind of lighting design service. Architect did put us in touch with an M&E specialist that I had a chat with but ultimately decided to do without. He seemed to cover the full monty of building M&E from a full life cycle perspective, i.e. considering maintenance as well as design and install. e.g. How are you going to clean your rooflights if you have a roof you cannot stand on, and no window to climb out onto the roof from ?

As said above the plan tends to change with first contact with the enemy, but as with the military only a fool has no plan and it is the planning process that counts and helps as you see the shell and make changes. We ended up with our own directly contracted sparky and his quote had a cost per switch/socket type breakdown, but in the end it got messy and we just paid him as we went on a time and materials basis.

 

BIG TIP - Make sure you marry up your lighting plan with the structural engineers beam and joist plan. I think almost no-one does this, we didn't. But you can't put a downlight into a steel beam, or a ceiling speaker into a joist etc. Can get bloody complicated staring up at the actual beam and joist layout and trying to work out how the hell you can distribute your lights sensibly. Got the chippy to modify some joist work to make room for lights over the worktop.

 

Had a LOT of seperate lighting circuits and switches and roughly twice as many downlights as attached. Made my own numbered list of lighting circuits and stuck a square or oblong of alu tape on the wall where we wanted them with circuit number for each switch.

 

I think lighting is difficult - lumens/sqm, beam angle, colour temperature, CRI, circuits, layout, dimming, CCT, baffles, plaster-in, led tape.

 

PS don't forget garden lighting.

 

 

 

Edited 9 hours ago by Spinny

[mjc55]

electrical symbols are a fairly standard set of symbols.

 

My  Architects Pocketbook lists them and they were what I used when I did my drawings as an Architectural Technologist.