PD - another question I'm afraid!

[JudeA]

We are considering a loft conversion to our house in order to create 2 extra bedroooms. (The place felt nice and big when we bought it nineteen years ago with one toddler, but has shrunk considerably now we have three teenagers!).
I am trying to understand the rules as set out by our local council planning department, and clearly I'm a bit thick.
The house is a 1946 end terrace (run of 4 houses) and we have no immediate neighbours on one side, just an Eon sub station thing.
The floor space in the existing loft is roughly 6 x 6 metres and it is maybe just over 2m high at the highest point. I'd very roughly calculate this at just over 50 cubic metres, as it is a triangular prism shape. Does that sound about right?
We are thinking about extending the existing roof a little (over the garage - about 2m) and gabling the end (existing has a hip end). This would also create a bit of a first floor extension where the stairs to the loft could go to avoid losing most of the existing 'boxroom' to a staircase.
Anyway, I have read the planning guidance and it says...

Does this mean that the existing roof space can be increased by up to 40 cubic metres, or have I misunderstood? Because it surely can't mean 40 cubic metres in total, can it?

The loft will hopefully be only a part of the job that we'd like to do, so we will probably end up going for planning permission anyway, but I'm just trying to work out if we would actually have to. It's all so confusing!

Many thanks, and congratulations to anyone who has persevered to the end of this post!
Would be grateful for any thoughts.

 

[RandomGrinch]

Does this mean that the existing roof space can be increased by up to 40 cubic metres

Yes!

 

[JudeA]

Hurray!! I'd hoped so...

 

[RandomGrinch]

...and your current loft would be about 36 cubic meters!

 

[RonnyRaygun]

We are thinking about extending the existing roof a little (over the garage - about 2m) and gabling the end (existing has a hip end).

Hip to gable is permitted development but I'm sure you'd need planning permission to actually extend the roof over the garage. Happy to be corrected if wrong.

If you apply for PP then none of the other rules apply.

 

[RonnyRaygun]

This would also create a bit of a first floor extension where the stairs to the loft could go to avoid losing most of the existing 'boxroom' to a staircase.

In fact yes, you'll definitely need PP for a first floor extension...

 

[JudeA]

Thank you.
We will be submitting it for planning permission anyway - in fact we have already applied with a different plan which was promptly blanked so we're rethinking now. If they turn it down again then we might look at just doing a straightforward loft conversion so I'm trying to understand.
My next question is this...in building/planning terms are square metres and cubic metres the same?
My GCSE maths tells me that square metres is a measure of area (2 dimensional) and cubic metres is a measure of volume (3 dimensional) but our 'plan drawing friend' and 'Random Grinch' seem to imply that they are the same. I assumed that the height of the roof space would need to be included in the measurements, so our current loft would have a floor space of 6 x 6 m = 36 square metres, but would be 6 x 6 x the height in cubic metres.
Please explain if you can!
Many thanks.

 

[RandomGrinch]

36m3!

 

[JudeA]

Gotcha! Half base X height.
It's all coming back to me now.
Random Grinch are you a teacher? If not, then maybe you should be!! I won't tell you what my day job is , just that it's not GCSE maths! That was very helpful. Thank you so much for taking the time.
I will no doubt be back with more random queries later!
Happy Monday!

 

[tony1851]

Welcome to the RandomGrinch Appreciation Society!

 

[JudeA]

I am absolutely in the Random Grinch appreciation society. Very grateful for the help so far!
Not to push my luck, but...
re. the work I mentioned above. We have been trying for over a year to get things moving and worked with an architect/designer chap (at significant expense) to get plans submitted. After very many wasted months we realised that this man was not the person to help us. We've pretty much cut our losses and tried not to think about the wasted money and how many bricks/roof tiles we could have bought with it!
The planning officer from our local council has been quite generous with her time and has spoken to us directly to explain why our original plans were rejected. (We now know that they were never in a million years going to be accepted and we should have been advised of this prior). We currently have someone else discussing plans with us. He has done a couple of rough pictures on his computer software which we have sent to the planning officer who has indicated that this looks more likely and that she would like to see elevational plans for this option. What she did point out is that :

"The rear dormer is concerning due to the size. We have a policy (Policy 17 of the Part 2 Local Plan) which states that dormers should not dominate the roof slope and this would contravene this. It could be reduced (but significantly) and could be broken into two to reduce its size but if you think this would not give you the floor space required then I wouldn’t recommend exploring this option."
​

These are the pictures she saw:

Top is a front view (just the bit with the black roof is ours) and bottom is a back view where you can see the dormer clearly. It is pretty big, I can see that and it could be divided into 2 as there will hopefully be 2 bedrooms up there. My question is, will there be any kind of 'formula' or measure of size that will determine what constitutes "domination" of the roof slope? I'd rather make changes now before paying for elevational plans.
I have spent a number of happy hours simply googling images of Dormer loft conversions, and this kind of size looks fairly usual. In some of them the Dormers are just massive! And isn't it likely to dominate the roof slope anyway? Hope someone can make some sense of this!
Any thoughts welcome.
Thank you x

 

[RandomGrinch]

No need for any appreciation.
Just happy to help if I can, but I'm also just a DIY'er - so could be very wrong

I know our local authority has a planning portal, that allows searching for developments in the locality.
If you can find plans for a build similar to yours, you may get:

A). A better idea of what may be passed.
Or B). A prior example that you can take to planning and ask 'if this passed, why won't ours!'

...other than that, you could use Google maps satellite view to find any dormers around you and have a wander over, to see what they look like!

I hope that helps, a little

 

[JudeA]

Another question...if anyone has time.
Our local planning officer has indicated that the rear dormer on our proposed loft conversion would need to be reduced in size 'significantly' in order to get planning permission following the guidance in the Borough Council 'Local Plan'.
Is it the case, that if we were to do a more 'standard' loft conversion under permitted development, we could have whatever sized dormer we liked? I have been to view a friend's loft that was completed December 2019/ January 2020 in the same local area as us. The Dormer is similar in size to our proposal and this wasn't any problem. Do building control make recommendations around deign, or just about quality and safety compliance?
I'm really confused. Still.

 

[RonnyRaygun]

If you can comply with the rules and restrictions of permitted development, the planning department will not get involved.

Building Control will only be interested in compliance with the building regulations.

Why does your dormer contravene the local plan?

 

[JudeA]

RonnyRaygun, thanks.
See my post on this thread from 1st December. It's just a few messages up.
Just seems so stupid that we could keep the Dormer as per the drawings if we don't involve the planning dept. but they won't allow it if they are involved. Pointless legislation, and so completely subjective.
There are dormers similar to our proposed one all over the area. And it is rear facing anyway, so won't even be visible from the street.
Thank you for clearing that up - it is as I suspected.
Think we'll reduce the size of the Dormer and split it into two, and submit it. See what happens.
We probably stand to gain more room by extending to the side before converting the loft than we would lose by reducing the Dormer. Maybe. It's hard to tell until we get plans drawn. And I'm reluctant to pay to get plans drawn for something that won't be accepted for planning. Grrr!
Thank you for your time.
I'll be back musing about something else soon, no doubt.