Knock down detached garage to build a self contained annex

Section62

mrsmsebastian said:

FreeBear said:

mrsmsebastian said: Why can't I use the existing base, I dont see any cracks to it and seems quite thick. I will only go for a self-contained cabin.

If the slab is large enough, no reason why you couldn't put a cabin on it. Comments about planning, building regs, and council tax still stand if this is going to be self contained - Even if it isn't a self contained unit, any electrical work needs to be certified, and a connection to the foul sewer for the toilet will need building regulation approval.

As for the opinions of a mortgage lender, you will need to talk to them directly. Some may be happy, others, possibly not.

Do I need to approach the builder first, are they going to supply the drawings needed to obtain for PP and BR?
Or Do I need to pay for an architect to draw the cabin first then builder to build it? 
Sorry for being stupid

Architect first. Then planning. Then building regs.  Then find a builder.

Otherwise you risk finding yourself a builder who (falsely) tells you not to worry about the other stuff and just build whatever you want.

mrsmsebastian

Section62 said:

mrsmsebastian said:

FreeBear said:

mrsmsebastian said: Why can't I use the existing base, I dont see any cracks to it and seems quite thick. I will only go for a self-contained cabin.

If the slab is large enough, no reason why you couldn't put a cabin on it. Comments about planning, building regs, and council tax still stand if this is going to be self contained - Even if it isn't a self contained unit, any electrical work needs to be certified, and a connection to the foul sewer for the toilet will need building regulation approval.

As for the opinions of a mortgage lender, you will need to talk to them directly. Some may be happy, others, possibly not.

Do I need to approach the builder first, are they going to supply the drawings needed to obtain for PP and BR?
Or Do I need to pay for an architect to draw the cabin first then builder to build it? 
Sorry for being stupid

Architect first. Then planning. Then building regs.  Then find a builder.

Otherwise you risk finding yourself a builder who (falsely) tells you not to worry about the other stuff and just build whatever you want.

I still need an architect for a self-contained cabin? Seems I need to spend a fortune for it. Do you have a rough idea for the cost with all these requirements with the type of cabin I want? Its okay if none, still grateful for your advise

Section62

mrsmsebastian said:

Section62 said:

Architect first. Then planning. Then building regs.  Then find a builder.

Otherwise you risk finding yourself a builder who (falsely) tells you not to worry about the other stuff and just build whatever you want.

I still need an architect for a self-contained cabin?

Unless you feel confident doing technical drawings yourself?  Or could persuade the building manufacturer to draw up all the plans for you free of charge?

mrsmsebastian said:

Seems I need to spend a fortune for it.

Building habitable space is not cheap.

mrsmsebastian said:

Do you have a rough idea for the cost with all these requirements with the type of cabin I want? Its okay if none, still grateful for your advise

I would budget around £3k to £5k for the plans/approvals process, if it costs less you'll have some spare cash for any overruns in the construction budget (final construction cost is rarely the same as the estimated cost).

FreeBear

Section62 said:

mrsmsebastian said:

Section62 said:

Architect first. Then planning. Then building regs.  Then find a builder.

Otherwise you risk finding yourself a builder who (falsely) tells you not to worry about the other stuff and just build whatever you want.

I still need an architect for a self-contained cabin?

Unless you feel confident doing technical drawings yourself?  Or could persuade the building manufacturer to draw up all the plans for you free of charge?

There are companies out there that will do a turnkey package that includes design, planning, and construction. But it isn't going to be cheap, and planning may well be refused for a self contained unit.

GDB2222

mrsmsebastian said:

FreeBear said:

Your average up * over garage door is roughly 2.1m wide and 2.1m high - It looks like you might have something a bit narrower (maybe 2m). For a practical habitable space, you need a floor to ceiling height of around 2.4m - You are not going to achieve this once sufficient insulation has been incorporated. The same problem applies to the width - There is no way you are going to get a 2.6m wide room out of a structure that is only 2.1m in width.

Simply put, it needs demolishing (including the base), proper foundations put in along with well insulated walls & roof. You will need planning permission from start to finish. You could use a prefabricated shed cabin, but it will need planning & building control sign off if you are thinking of having it as self contained unit. In addition, it would be subject to its own council tax banding.

Why can't I use the existing base, I dont see any cracks to it and seems quite thick. I will only go for a self-contained cabin. And if I build the cabin I want, will that annex put off lenders if I remortgage 10 years from now as I heard they dont like annex?

One snag is the connection to the drains. You need a trench dug through the concrete base. It can be done, but it’s a bit of work. 

in_my_wellies

GDB2222 said:

mrsmsebastian said:

FreeBear said:

Your average up * over garage door is roughly 2.1m wide and 2.1m high - It looks like you might have something a bit narrower (maybe 2m). For a practical habitable space, you need a floor to ceiling height of around 2.4m - You are not going to achieve this once sufficient insulation has been incorporated. The same problem applies to the width - There is no way you are going to get a 2.6m wide room out of a structure that is only 2.1m in width.

Simply put, it needs demolishing (including the base), proper foundations put in along with well insulated walls & roof. You will need planning permission from start to finish. You could use a prefabricated shed cabin, but it will need planning & building control sign off if you are thinking of having it as self contained unit. In addition, it would be subject to its own council tax banding.

Why can't I use the existing base, I dont see any cracks to it and seems quite thick. I will only go for a self-contained cabin. And if I build the cabin I want, will that annex put off lenders if I remortgage 10 years from now as I heard they dont like annex?

One snag is the connection to the drains. You need a trench dug through the concrete base. It can be done, but it’s a bit of work. 

Exactly this ^^^
We had a concrete slab in good condition and as the workshop/cabin was larger we initially thought we could build round it, however, by the time surround was dug to extend the area and trenches dug across it we decided to clear the lot. One skip and a hard day but this enabled the ground to be lowered so there is very little step into the workshop making access easier