We want to convert the loft on our Victorian end terrace house to add a master bedroom and ensuite. For some reason best known to the Victorians our original roof design is different from all other houses in the street and immediate neighbourhood. In addition to having a hip roof it also has an unusually low pitch, which means that the existing volume under the roof is really tiny for a house of this style and footprint. Based on a precedent in our neighbourhood we successfully applied for householder planning permission to raise the ridge. However, our architectural designer has not been able to come up with a satisfactory design for the extension that complies with the volume restrictions under PD. Whereas many neighbouring properties have been able to extend over both the main roof space and the rear outrigger, gaining sufficient space for two bedrooms or one bedroom and an ensuite, our low existing volume means we only have enough volume for a dormer over the main bit of the house, which would be insufficient for a bedroom plus ensuite. It's been suggested to us that there is no point applying for householder planning permission for a larger extension, as the volume increase under PD is the maximum we would ever get. Is this right? Ideally we would like to build an extension which would look indistinguishable from what many of our neighbours already have, it's just that because our existing roof volume is so low we would need to add more volume than the neighbours to achieve the same end result. Is there any point making this argument or would we simply be flogging a dead horse?
Planning approach for loft conversion with low existing roof volume
- Thread starter TrixC
- Start date
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Planning permission granted - tick.
Then you say....
So why did you not just apply for planning permission for the larger volume jobby?
If you have raised the roof ridge or have planning permission to raise the ridge you will not have any permitted development rights to enlarge the "new" roof. Any enlargement by way of a dormer etc. would need a new planning application. (unless I have completely misunderstood the question)
We were following the same approach as had been successfully used for a house in the next street - they got householder planning permission for a ridge raise only, and then separately applied for PD for the dormer loft conversion (but did the construction as a single project). However they were lucky enough to have an existing gable end so they had more volume than us to begin with. If it weren't for this precedent I guess we would have submitted a single application for the ridge raise plus loft conversion - I'm unclear whether such an application would have succeeded. Several people told us we wouldn’t get permission to raise the ridge until we pointed them to this neighbouring property. Basically everyone we talk to tells us something different and I’m not sure who to believe.
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Permitted development only applies to the original house not newer extensions, raising the ridge is a roof extension. Enlarging the new roof is an extension to an extension and not permitted development.
Having said that a lot of Planning Officers are incompetent muppets who do not understand their own rules so I would not be at all surprised if one of your neighbours managed to secure similar work under permitted development.
I have managed to get planning permission a few times for similar by arguing that the dormer would have been permitted development (the dormers were within the volume limits but not the entire roof additional volume) if the roof ridge had not been raised. Although it surprises me every time I get away with it, I hate big flat roof dormers but it does create a lot of space so clients love them.
Having said that a lot of Planning Officers are incompetent muppets who do not understand their own rules so I would not be at all surprised if one of your neighbours managed to secure similar work under permitted development.
I have managed to get planning permission a few times for similar by arguing that the dormer would have been permitted development (the dormers were within the volume limits but not the entire roof additional volume) if the roof ridge had not been raised. Although it surprises me every time I get away with it, I hate big flat roof dormers but it does create a lot of space so clients love them.
Our Council's approach seems to be that extension of the new roof can be treated as PD, but we need to include the additional volume associated with the ridge raise as part of the calculation. This is the bit which is creating issues for us - if we didn't have to include the volume associated with the ridge raise we would have plenty of volume to go ahead with the conversion. I guess what I'm trying to understand is whether it's true that the volume additions allowed under PD are considered the absolute upper limits of what would ever be allowed under PP, or if there are circumstances where larger extensions might be approved. In our case the finished result would appear entirely consistent in the context of the neighbourhood.
Can you post a screen shot of your house from the 3D satellite image off Google Maps? (without the address).
It's difficult to visualize what you are after and a pic might elicit more suggestions.
It's difficult to visualize what you are after and a pic might elicit more suggestions.
I’m not sure what you mean, do you mean the aerial satellite image?
Yes.
If you've raised the roof I don't see how you can add a dormer to the new roof under permitted development in any sensible way. I don't think your issue is the volume and whether the volume of the new part of the roof counts towards your 50m3 limit, because you created the new volume under a Planning approval.
The issue is that if the council applies the rules correctly, the dimensions of the dormer should be limited by the dimensions of the old roof. The standout there is that you can't go within 50cm of the old ridge, so Permitted Development limits you to a dormer that sounds like it'll be too short to be of any use. Where volume will come into it is that where that dormer is 'inside' the new roof space that volume will count against your 50m3, but I think you've hit a show-stopper before you get that far.
But there's not obvious reason why planning permission would be refused, certainly permitted development rules aren't defining maximum volumes for approvals. If you are building to match an existing precedent, that will help, if you're not in Conservation Area then that will help. I would get a local planning consultant with a good track record involved for advice and potentially to take it forward. It's worth investing in this upfront if you think it's high-risk of refusal.
For context, we have a detached victorian house that sounds similar to yours, though without a low ridge, we're in a Conservation Area. We have permission for three large skylights facing the highway, a dormer that's 2.5m high, 2m wide and within 200mm of the ridge, 300 of the eaves to one side of the roof to the rear. Where we have the 'outrigger' sticking off the back of the main house we have permission to take that to three stories with effectively a very large dormer extending from the main roof to cover all of the outrigger.
The issue is that if the council applies the rules correctly, the dimensions of the dormer should be limited by the dimensions of the old roof. The standout there is that you can't go within 50cm of the old ridge, so Permitted Development limits you to a dormer that sounds like it'll be too short to be of any use. Where volume will come into it is that where that dormer is 'inside' the new roof space that volume will count against your 50m3, but I think you've hit a show-stopper before you get that far.
But there's not obvious reason why planning permission would be refused, certainly permitted development rules aren't defining maximum volumes for approvals. If you are building to match an existing precedent, that will help, if you're not in Conservation Area then that will help. I would get a local planning consultant with a good track record involved for advice and potentially to take it forward. It's worth investing in this upfront if you think it's high-risk of refusal.
For context, we have a detached victorian house that sounds similar to yours, though without a low ridge, we're in a Conservation Area. We have permission for three large skylights facing the highway, a dormer that's 2.5m high, 2m wide and within 200mm of the ridge, 300 of the eaves to one side of the roof to the rear. Where we have the 'outrigger' sticking off the back of the main house we have permission to take that to three stories with effectively a very large dormer extending from the main roof to cover all of the outrigger.
Where does this rule come from? The PD rules simply say it must not go above the original ridge.
Very helpful thanks. The example in your last paragraph sounds similar to what we were hoping to do, although our house is end terrace, not detached. Basically the volume restriction under PD means we can’t extend the dormer out over the outrigger, even though that’s the standard approach to loft extensions in these parts and two of our immediate neighbours have recently done it. We’re not in a conservation area. Did the example you mention add more volume than would have been possible under PD?
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