Could you do a very slow, DIY loft extension

[KatyMac]

Doing each bit, as you can afford it and taking maybe years?

Did the rules change for planning permission a while back - would that make it easier?

TBH if we had a staircase to get into the loft space it would make our lives easier even if we did nothing else

Yes. It is allowed under permitted dev as long as younuse velux not dormer I think and it's not a conservation area. Your council will have details on it's website. Younwill need building regs

So could I do:
Staircase
Floor
Walls
Then apply for PP to put in the dorma windows last?

I am pretty sure you only need planning permission if you want to make it a habitable room - so if you want to just use it as a store room to begin with you can out all that in without and permissions. You will probably need to check permission of you want to put in windows.

You do need to adhere to building regs though - check with local building control - they will inspect what you do and certify it is safe.

You don't always need planning permission for dormer windows. Building regs are more tricky if you would intend the room to be used as habitable space (and to market it in the future as an additional bedroom).

Rules apply re fire escape/fire doors/ stair case treads and so on.

Insulation is something else tat building regs guys look at, and ventilation.

I'd want each stage to be done 'properly' so Building regs would be necessary

Speak to your local planning department and see what it is you are able to do with or without planning permission and also speak to the Building regs department. They are often more than happy to help. Although some planning departments now charge a small one off fee (ours is £25) for consultations, but you can speak with them as many times as you need to.

It would also be wise to have some drawings done.

I think there is no time limit to building control inspections (unlike planning permission which I think is 5 years). Ours took so long they had to keep getting the paperwork out of the archive !!

You only need planning for dormers if
i) it is on the pavement face of the roof (so the back or side is gen ok) or
ii) you are building above the current highest point of the roof

My dad is a structural engineer & worked as a building contractor; but he is too ill to do the work now

I think he would manage the drawings still (but in imperial - he would have to convert to metric; he hasn't done it in a while)

Just had an enormous loft conversion done - converted hipped roof to gable end and massive dormer across the back, put in big master bedroom, shared shower room and child's single room - no planning permission required as no work to front elevation, and no development above original roof height. Building regs obv. required tho. We had a builder to do the work though [thought of DIY taking years filling me with dread - was bad enough with it taking three months!]. FWIW the staircase is usually the last thing to be put in about two weeks before the finish (they did all the other work from the scaffolding on the outside, which was great as minimal disruption inside [three small DC!])

Might be worth getting quotes for 'part conversion' - our builder would have done all the structural work and let us do the insulation, plasterboarding, electrics, bathroom fitting etc if we'd have wanted that. Also, some builders can do their own drawings and do them for free as part of the quote, ours did.

Yep the scaffolding is the bit I want to minimise

If we did the staircase first with a door at the top and hung polythene/dustsheets that would be sort of OK I guess

DD is 14 so there isn't quite the issue as with smaller children

Most importantly, don't cut through the floor until you have done all the dusty crappy work! or you will need to replace most of your carpets in the rest of the house

Oh dear; the stairs (even just for storage) would make my life easier.....

This might actually happen

I think I need:
A new loft access hole cut with a new ladder
Old loft access plastered over
A window put in the gable
Paint the gable wall (or possibly insulate then paint)
To insulate the roof (can I do this with a staple gun, tape & loft insulation?)

My dad is calculating the supports the floor needs & I won't be able to work out the costs for that yet; but can anyone help me with costs for the other things?

& scaffolding - how much is scaffolding?

You would probably need planning permission for a gable window. Council should have guidance on their planning website.
You may be able to do the rest without PP as it's internal works, although not necessarily if you live in listed building or conservation area.
Planning permission is usually granted for 3 yrs however you usually only have to start building work (usually a significant start required) in this time not necessarily finish it.
BRegs will def be needed (new stairs, insulation, windows, electrics, structural calcs for beams, fire doors & alarms, plumbing etc) but I'd phone them and have a quick word about your plans and ask your local council BControl officer how they would suggest doing it.
You will probably need to upgrade the doors on all doors to your escape from the loft to gf exit to fire doors + install integral alarm before they will sign off in respect to fire escape.

I think as long as it isn't habitable space, I won't need BR approval & I'm fairly certain I won't need planning permission under the new rules

You will need BR approval for any new windows, structural support, stairs and electrics even if its not habitable.
Insulation, plumbing and fire stuff generally only if it's habitable.
However if window is installed by fensa approved person - they can self certify.
Some electricians can self certify too.

Getting building regs isn't as onerous as planning and generally is a process of checking that you've done work safely and to a minimum standard.

BR means it's a complete nonstarter

Oh poo!

I feel a shed coming on

Why does getting BR mean it's a complete non starter? It's honestly a lot less hassle than planning.
You only need signoff when each section of work is finished (although they may want to inspect things like steels before they are covered up) there is no reason why you couldn't do the work overtime as long as you get sign off at the end.
You will need to submit plans and then get an inspection once that bit of work is done.
Speak to your local Building control before dismissing the idea - they are usually a bit more friendly than planning and will usually give advice for free.

because by the time I have bought 6 fire doors, blocked up an arch, increased the depth of the rafters to put in extra insulation, put in a fixed staircase, isolated the electrics on a separate circuit in addition to the bits I want I will quadruple the cost

If you can't afford to do it to building regs standard then you shouldn't be doing it tbh. Go for the shed - you can get some lovely sheds.

Oh I agree
Most of the BR stuff is fine but 6 fire doors & insulating it more than the rest of the house is insulated seems a bit daft as does the separate electric tbh

You'll only need fire doors if it's going to be a habitable room. If you are going for accessible storage space then you won't. You may not need new doors depending on what you've already got. If they are solid timber doors in good condition they are acceptable as they already have half hour resistance, if you put closers on them. You can get chain hinge closers for about £2.50 each (most of ours came off when we moved in post BR approval because they are a bit of a pain)