Where to start?! Dormer Window behind bedroom.

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I'm struggling to get a good start with a project I'd like completing.

I've spoken with a builder who looked at the project and gave a few ideas but suggested that I get an architect / structural engineer to work out the best solution first then they could quote properly.

I contacted a few companies but have had what I consider to be very high quotes (perhaps that is just me!).

Anyway - what I'm after is as follows:

Our bedroom is 4m x 4m and sits above our garage which is 7m x 4m. Our bedroom was added as an extension about 25 years ago. Our bedroom sits level with the garage at the front and has a short roof at the front, then a long sloping roof at the back which goes all the way down to the single storey rear.

We therefore have a bit of a sloped ceiling on the back edge of our bedroom and then a wall. The wall has a short door in it to access the space behind which we use for storage.

We want to put a dormer window in this space to create an extra small room of about 2m x 2m to give us an en-suite. The floor in this space is identical to the rest of the bedroom with the same joists running at the same gap (400mm)

So I'm a bit confused as to where to start, I thought a builder was the correct place but as I would like quotes from a few, the builder pointed out they need to know what to quote for. So I need to sort out the planning side.

I'm 99% sure from reading the planning website that it won't require planning permission. I take it, that it would be just adding a dormer and wouldn't be counted as a loft conversion?

I realise that I would need building regs - what sort of cost should this be?

I need a structural engineer to work out how to move a roof beam which will be in my way.

And I think I need an architect to draw up plans for the builder to work from which will comply with building regs.

I know it varies a little from area to area, but how much should this kind of work cost? I've had a variety of quotes which all seem high and to be honest they aren't clear if they cover everything I need or not. Is the above everything I should need before I get the builders to quote?

I wanted to fit the bathroom myself - so really just want the dormer itself building (including having the beam removed or altered), the window fitting, major plumbing works done, electrics done and then left for me to fit a shower, toilet, sink, flooring and to tile the walls.
 
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Although it may seem like a roof enlargement which would not need planning permission, it is in fact enlarging a 1st floor room on a side extension and so would need planning permission.
 
You don't need an architect, look for a one man band architectural technician who will (should) be significantly cheaper.
 
Although it may seem like a roof enlargement which would not need planning permission, it is in fact enlarging a 1st floor room on a side extension and so would need planning permission.

I will contact planning just to check but I had sort of satisfied myself that it wouldn't need permission.

I read the permitted development and it talks about roof space not being increased by more than 50 cubic meters, it includes dormer windows in references that it talks about.

One such quote is:
The effect of this is that dormer windows as part of a loft conversion, or any other enlargement of the roof space, are not permitted development on a principal elevation that fronts a highway and will therefore require an application for planning permission.

It doesn't front a highway as it is at the rear. Surely the area is classed as roof space? It wouldn't extend out any further, the floor space for the dormer is already there, it would just be reworking the roof to create the dormer. This wouldn't increase the volume by more than the permitted space and wouldn't be higher than the ridge of the house. It would have obscured glass so, with any openings above 1.7m.

As I say I will contact planning to double check but how else would you class what it is now other than roof space? It is uninsulated currently, just like any other loft. It just happens to be on the first floor above the single storey part of the garage.
 
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You don't need an architect, look for a one man band architectural technician who will (should) be significantly cheaper.

Will they be able to do the structural calculations, or would they get that done, or would I need to get that done first?
 
Will they be able to do the structural calculations, or would they get that done, or would I need to get that done first?
Unless they were suitably qualified and had the necessary insurance they would use an engineer, as would any designer. An engineer will need a design first.
 
You misunderstand the application of the permitted development rules.
At first glance, your project appears to come under class B ('enlargement...consisting of an addition/alteration of a roof'). However, any development must satisfy all classes of the p.d. rules, and yours must also be judged against class A ('enlargement... of a dwelling' etc).
Presumably, your garage is on the side of the house? If so, the bedroom on top would have needed planning permission because any two-storey side extension needs planning permission. Because your proposed enlargement is on the side of the house and is an extension of an existing 1st-floor extension, the whole lot (ie existing bedroom extension plus proposed rear dormer) would be regarded by the council as one unit for Planning purposes, and would therefore need planning permisssion.
 
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Right looking at planning permission, it looks like I need to pay £67 just to enquire to see if I need planning permission.

The garage is to the side of the house. I have dug out the original architect plans for the extension from the 80's. The garage was extended out to the side my about 1.2m, then the bedroom was built above. Planning permission was obviously granted for this development.

I don't want to extend the building as such any further and the floorspace is already there, but I want to make a small dorma, this will add at most 8m3 of roofspace.

Given that the fee to even enquire is £67, and you sound certain that I would need planning permission, would I be better just to apply for planning permission from the outset and save the £67?

I'm also really struggling to find any information about extending an extension that previously had planning permission.

Thanks
 
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Get some fee quotes from local architectural designers, should be around £750 to £1000 for Planning and Building Regulations drawings and applications (excluding Council's application fees). If you need a Structural Engineer anything from £200 to £500 extra. The chosen designer should be able to advise you on Planning so don't waste your money paying the Council for confirmation.
 
Get some fee quotes from local architectural designers, should be around £750 to £1000 for Planning and Building Regulations drawings and applications (excluding Council's application fees). If you need a Structural Engineer anything from £200 to £500 extra. The chosen designer should be able to advise you on Planning so don't waste your money paying the Council for confirmation.

Thanks, that was my original plan. The quotes I've had however have been around £2500, which I thought was too much. I've had a builder come out and have a proper look now. He said the CAD drawings I've done would be sufficient for both planning (if necessary) and building control. So I now don't know if I even need an architect! He said building control would tell them if they needed structural calcs and they could sort them with a local company for a couple of hundred pounds.

I've read the guidance a couple of times now, and it really isn't clear about extensions to existing extensions. It talks about taking into account the additional roof space that was added last time, which is difficult to calculate exactly. Does the bedroom in the extension count as roof space?? When the bedroom was added the actual cubic 'loft' space above and behind the bedroom became less than it was before. If it does count the bedroom then I'm sure it is less than 40m3 added. The dorma will add less the 10m3 so the whole lot will be less than 50m3. I can't find anything that says anything else.
 
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At first glance, your project appears to come under class B ('enlargement...consisting of an addition/alteration of a roof'). However, any development must satisfy all classes of the p.d. rules, and yours must also be judged against class A ('enlargement... of a dwelling' etc).

I'm in the middle of a 2 storey extension to a chalet bungalow (ie one where the entire first floor is in the roof space). It complies with class a (at a scrape) but if I was to apply for an ldc would they also assess it under the loft conversion class-b rules or is that a silly interpretation of application of the rules?
 
I've read the guidance a couple of times now, and it really isn't clear about extensions to existing extensions. It talks about taking into account the additional roof space that was added last time, which is difficult to calculate exactly. Does the bedroom in the extension count as roof space?? When the bedroom was added the actual cubic 'loft' space above and behind the bedroom became less than it was before. If it does count the bedroom then I'm sure it is less than 40m3 added. The dorma will add less the 10m3 so the whole lot will be less than 50m3. I can't find anything that says anything else.

There's no permitted development for extensions to extensions. It all falls under the same permitted development rights for the original extension. Just consider whatever your attaching the extension to isn't there - then judge whether or not permission is required for the original extension including your extension.

E.g. If you build a 15m deep conservatory (thus requiring permission) with a flat roof and a few years after completion you want a pitched roof on it, even though the pitched roof may comply with the height restrictions under Class A, it will require consent as all of the extension including the new proposed pitched roof will be greater than the permitted development allowances.

In general, if you want to make any amendments to anything that originally required planning permission, you are going to require permission again (as per Freddie and Tony above)

I'm in the middle of a 2 storey extension to a chalet bungalow (ie one where the entire first floor is in the roof space). It complies with class a (at a scrape) but if I was to apply for an ldc would they also assess it under the loft conversion class-b rules or is that a silly interpretation of application of the rules?

As long as it complies with the Class A, I think its pretty unreasonable to apply Class B, however 'roof space' is defined as 'the roof space as enlarged, taking into account any enlargement to the original roof space, whether permitted by this Class or not.' So it depends on what the planning officer who picks it up. I reckon you would have a good chance of them not even twigging that Class B could apply in any case.
 
There's no permitted development for extensions to extensions. It all falls under the same permitted development rights for the original extension. Just consider whatever your attaching the extension to isn't there - then judge whether or not permission is required for the original extension including your extension.

E.g. If you build a 15m deep conservatory (thus requiring permission) with a flat roof and a few years after completion you want a pitched roof on it, even though the pitched roof may comply with the height restrictions under Class A, it will require consent as all of the extension including the new proposed pitched roof will be greater than the permitted development allowances.

In general, if you want to make any amendments to anything that originally required planning permission, you are going to require permission again (as per Freddie and Tony above)



As long as it complies with the Class A, I think its pretty unreasonable to apply Class B, however 'roof space' is defined as 'the roof space as enlarged, taking into account any enlargement to the original roof space, whether permitted by this Class or not.' So it depends on what the planning officer who picks it up. I reckon you would have a good chance of them not even twigging that Class B could apply in any case.


Yes depends on the Planning Officer / LPA but there is a reasonable chance they have read Government's Technical Guidance which clarifies this point:

In order to be permitted development, a proposal must meet all the limitations and conditions under each Class relevant to the proposal. It is therefore essential that any proposed household development is considered in the context of the permitted development rules as a whole in order to determine whether it benefits from permitted development rights and therefore does not require an application for planning permission.

For example, where a proposed two storey extension at the rear
[or side] of a house has a roof that joins onto the main roof of the original house, the works will need to meet the requirements of both Class A (which covers the enlargement of the house) and Class C (which covers any alterations to the roof) in order to be permitted development. If the works also include the creation of a dormer window to enlarge the roof space, either in the extension or the original roof space, then they would also need to meet the requirements of Class B.

Just to keep this one simple- Class A does not permit two storey side extensions so this 100% needs permission regardless of whether you apply Class B (which you have to).
 

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