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Garage conversion. No official plans. Builders reluctant to quote...

65 replies

LittenTree · 15/07/2012 14:40

If this were a bigger job, I imagine you'd call a builder in, you'd rough out what you wanted, he'd tell you stuff you didn't know, such as what size the 'units' are, i.e. it'll cost less, in the long run, to make that wall 3 units long not 2 3/4 units as it'll cost labour to cut a unit down by a quarter, etc etc. That certain sorts of lighting/heating ventilation are far cheaper to be built in, not retro-added. Like a window there wouldn't get past the council, but one here would, that this sort of flooring is way more economical than that, that this will need to be a fire door, that putting the WC there would make the soil pipe far cheaper to dig because we could attach it to that spur (that I wouldn't have even recognised as such!). And so forth.

BUT all the blokes I called have asked 'have you got yer plans drawn up, love?'

Well, no, if only because it might all come in at way more than we are willing to pay so the £500 spent out on plans would be money down the pan- and what we come up with might be rubbish (see above for all the sort of stuff that would occur to me)! A couple have said, well, if you're handy with a pencil, you can do your own plans but how much detail do they need? Wiring diagrams etc? DO any of the walls need to be fire proof? (yes, in fact). I wouldn't have a clue. BUT I don't seem to be able to get a quote, just 'ball park', without plans!

Any suggestions as to how we can proceed?

I am praying our 'odd job' bloke, who's just boarded the loft in preparation for a garage conversion can talk to his mate etc etc and that he'll effectively 'project manage' it all. But a local builder with local planning rules knowledge would be way better, if one would quote!

OP posts:
ecuse · 16/07/2012 18:39

Hey, OP. In completely unrelated googling I stumbled across this. Wonder whether it would help?

OliviaLMumsnet · 16/07/2012 18:50

@LittenTree

I'd really prefer not to have to come up with £500 before an experienced builder can give me 'a ball park'
Arf, but as my brother said to me, you don't want a ball park figure from the builder, as you're not building a ball park. Hmm Grinbadumtish
tricot39 · 16/07/2012 18:56

I agree with pigletjohn. You are expecting a lot and think you got lucky last time.

However it is possible to broadly price a job for budget purposes on a square metre rate. As someone else said up thread it can be anything upward of £500 per sq metre.

So sticking a finger in the air.....From the sound of it you will not be coming in at the gold tap end of the market over £3000 but you don't have to pay for walls/slab etc. so let's be optimistic and go for the 500 rate.

What are your garage dimensions? Say 6m by 3.5m? On that basis your budget price might be about 10.5k.......or maybe not and that excludes vat and fees. Your 6k sounds too little but the only way to know for sure is to get specific plans done.

LittenTree · 16/07/2012 20:47

Argh.

So I called 3 (three!) architectural technicians today, picking ones in my borough council (which I live at the edge of).

First said 'Sorry, too far to travel' (12 miles)
Next said his minimum fee was £620 (which was oddly precise!)
The third said he'd do it for £350 if I then use his 'recommended builder', or 'considerably more' if I didn't Confused. How does that work?!

I confess I wasn't expecting those responses!

I will have to get my graph paper out, I have no choice. Guess I'll have to wing it when (and if I can get a builder around!) asks ' what sort of rating does this have to be?' ..of say my fire wall. I'll say 'lilac'! And it'd be handy to know whether the linings of the walls will add 2 or 6" to the overall thickness of the internal walls; the minimum/maximum height a window has to be- I cannot make sense of the Planning Portal at all!- but hey ho.

The existing (as in 'unclad') internal walls give us a room 3m x 2.75m.

Thanks, ecuse for 'getting it'!

OP posts:
LittenTree · 16/07/2012 20:49

3.6m x 2.75 actually

OP posts:
PorkyandBess · 16/07/2012 21:02

Do you need planning permission? If you do, get plans drawn up. If no pp required, I wouldn't bother.

I'm a bco and look at garage conversions all the time. They are almost all done on building notices with no plans.

We usually meet the builders on site and run through the requirements of the regs in terms of insulation, ventilation, flooring and if a footing is needed at the front. Sometimes the slab is thick enough to build off, or it's possible to lintel from either side.

I would find some builders that maybe your neighbours have used for garage conversions and get a quote from them.

SoupDragon · 17/07/2012 07:42

Guess I'll have to wing it when (and if I can get a builder around!) asks ' what sort of rating does this have to be?' ..of say my fire wall. I'll say 'lilac'! And it'd be handy to know whether the linings of the walls will add 2 or 6" to the overall thickness of the internal walls; the minimum/maximum height a window has to be

Or you could ask those specific questions on MN. I bet PigletJohn knows the answers :o

LittenTree · 17/07/2012 09:08

It appears I'll need planning permission. I think it's because of the window! And to convert your garage you need to have 2 off road parking spaces (which we have, but they're not an oblong shape- that'd need verifying).

soupdragon- yes (re PigletJohn) but.... wouldn't someone need to actually come and see what we already have before being able to tell me what my flooring options are? Whether one could attach plasterboard straight onto the brickwork or whether we need to erect a frame to nail it on to?

Surely if I (or anyone else for that matter- they'll only draw what I ask them to!), a 'quoting' builder's first question would be 'what do you want doing with the floor? Floating?', 'How many ventilation points do you want?', 'What are your footings like?' etc.

And doesn't that bring me back to my OP?!

OP posts:
tricot39 · 17/07/2012 09:16

Is that the size of the proposed room? Or the existing garage?

PorkyandBess · 17/07/2012 10:08

The floor you create depends on the level of the garage floor now.

If it's level with the house you will make a step if you add insulation. Most people don't want this so you might be able to paint with bitumen.

If it's lower than the house, you could make a floating floor.

You are also going to have to upgrade insulation to the walls and roof to meet the required U values and provide sound proofing on the shared wall.

I would advise you to dig a trial hole to expose the front. There may be a foundation or a reinforced slab that may be suitable to build off.

The wall separating the old part of the garage from the converted bit needs to be fire rated (30 mins). If the door from the garage does not lead directly to a hall with a door to outside air, or have its own door to outside, then a means of escape window is required.

Any reputable builder that is experienced in garage conversions should be able to come round and tell you exactly what is required to meet the requirements of the regs. The electrical work has to be certified, so I'd check that the builder uses a registered for Part P electrician, otherwise your b regs will cost more.

tricot39 · 17/07/2012 11:51

I found this pdf guide from LABC when I was looking for something else today. It might help you with spec notes:
{{http://www.labc.uk.com/Media/Default/library/HO0050112_Conversion_of_Attached_Garages_to_Living_Space.pdf]]

tricot39 · 17/07/2012 11:51

doh!

SoupDragon · 17/07/2012 12:25

Q: "what do you want doing with the floor? Floating?',
A: What are my options?

Q: 'How many ventilation points do you want?'
A: What do you recommend? What is the minimum I need?

WRT the walls, even I can tell that one side of my garage is the original external house wall and thus single brick and the other walls are all breeze block and I would expect someone to be able to tell me from that what the options re insulation/plasterboard etc are.

LittenTree · 17/07/2012 15:01

Thanks for the helpful thoughts, am reading the link right now... (though, porky "Any reputable builder that is experienced in garage conversions should be able to come round and tell you exactly what is required to meet the requirements of the regs.."- hereby lies the problem. I can't get a builder to come round Grin).

Currently you have to step down into the garage which is good as that means we can build up the flooring to the house level with the required insulation- whatever that might be! The door opens into the hall but I'd have a window that met fire escape regs, too.

The house is a 12 year old 4 br 'estate' house so it would be my thought that the external wall of the (integral) garage is the house external wall.

OP posts:
Fakeblondie · 17/07/2012 16:12

well I'm prob going to get slated for this but here goes.
Conceived dd 4 3 years ago and living in 3 bed semi.
BIL a builder came and removed garage door levelled floor with lots of concrete and more insulation I think insulated Walls and ceiling plaster boarded painted and fitted. Double glazed windows front and back. friend an electrician put electric in . BIl put fake wallmin middle which gave dd, s a small 8 x 8 room each. Plugged in oil filled radiators which means we've not made it a permanent dwelling. Put in carbon oxide and smoke detectors. trip t ikea to decorate. Fire door anyway to what was garage. Loft hatch and loft boarded and insulated. beautifully warm as rest of house is single glazed ! Whole lot cost less than 3 thousand and we had no permission of any sort.Was very worked at one point but apparently now it's been done 2 years we can't get into trouble . girls have lovely rooms.Wrong I know but that's what we've done.

Fakeblondie · 17/07/2012 16:13

Sorry re grammar it's my iPad honest !

LittenTree · 17/07/2012 16:49

Is it really only 2 years before it becomes 'legal'? Or is that Council dependent?

I will be doing it through the proper channels, but it's interesting to hear what you've done, fake.

Just discovered that yes, I will need Full Planning Permission for our Council Sad.

OP posts:
Pendeen · 17/07/2012 16:57

"... and we had no permission of any sort. ..."

I would keep very quiet about that Fakeblondie because it's really rather naughty.

tricot39 · 17/07/2012 19:05

It is rather naughty but highly unlikely that the "building police" will be around. However the problem normally comes whenwhen you want to sell. Unauthorized building works will put lots of buyers off and/or reduce the value of your property.

I am also sceptical about the 2 years. It is 4 years min for planning in England assuming no complaints.

Erebus · 17/07/2012 19:10

I recall having to go to the Council (this was in Oz) regarding PP for a swimming pool on the property we were selling, put in before we bought (but much appreciated afterwards!). Getting 'the paperwork' from the council would've cost us £75-odd, BUT I was very lucky. After queuing at the Council offices, the lady behind the counter asked me what it was for, I told her 'selling the house', and she said, 'Well, off the record I can tell you that PP was applied for and granted, is that sufficient?'

Yes, yes, yes! But if it hadn't had PP, we would have had to have applied for it retrospectively .

Fizzylemonade · 17/07/2012 20:03

The issue with doing it without permission is indeed when you go to sell, personally I viewed a property where they had illegally converted the garage and it made me wonder what other corners were cut.

You can't sell it as X number of bedrooms if one of them is illegal, to get retrospective building regs they will most probably want to take up part of your floor and pop a hole in the wall to see what is underneath and behind (my friend had this done to her)

Moral of tale is planning permission here is about £150, building regs £350 IIRC so for the sake of £500 is it worth not having the paperwork?

Planning isn't the issue, it's the building regs and personally I wouldn't want any house without the building regs.

For my own garage conversion the building officer came out 3 times, once to see the relocation of the soil pipe, the builders had to leave the hole in the floor and only cover it once inspected, once in the middle of the build to check insulation/flooring etc and again at the end when it was finished to sign off on it. Hardly a hassle if your builder is legit and knows what they are doing.

ecuse · 17/07/2012 20:04

It's 4 years for planning, 1 year for buildings regs before it's legal. But you should probably expect it to give future purchasers a wobble and to have to buy an indemnity policy for them. They're usually £150 or less though.

ecuse · 17/07/2012 20:05

Sorry - to clarify - br not 'legal' after a year but council only have a year to do inspections.

Pendeen · 18/07/2012 11:17

If the work is very sub-standard then there is no time limit.

fossil97 · 18/07/2012 15:05

I think architects or arch. technicians will normally come round and give you a half hour consultation for free. If they are any good they should be able to give you an idea of what similar jobs they've designed, have costed and help you to decide whether to go ahead. I would think about £10k but it might be a bit less if the house is modern and garage already had decent walls etc, and you are economical with your specification. Does your budget include finishes - some people can spend £3000 on flooring alone...