outdoor studio-pent roof-slope which way?

[Pepeluis]

Hello,

a lot of great info and help on this forum. I am a novice at studio design but have gained a greater understanding of the basic principles from experts on this forum

I am having a one room recording room built in my back garden, intended as a writing/recording room for myself alone most of the time. I am not intending to have band rehearsals or any live drums etc. loudest instrument would be occasional congas/percussion and acoustic guitar plus KRK RP5 monitors.. (don't currently have SPL resdings)

Structure will be (from outside to inside)

timber frame (floor area 4x5m)
OSB with 18 mm shiplap cladding
4x2in wooden studs
50mm RW3
2 layers of 15mm acoustic plasterboard.

External Dimensions-4mx5m
roof height-2.5m (maximum allowed subject to UK permitted development rules)
1m distance from adjacent boundaries (wooden fences at back and one side)

The builder is laying the base next week and we have discussed options regarding the roof and internal ceiling.

The roof will be a pent roof with a height difference for drainage of approx. 4 inches from high to lower side. Options for roof are

1) sloping from long side to opposite one or

2) from narrower side to opposite.



apologies for my rudimentary sketchup drawings, angles are not accurate but for illustration.

I can choose to have a horizontal internal ceiling at height of lowest roof side (loss of 4 inches ceiling height all round) or following the same slope angle as the external roof with ceiling remaining parallel to roof. (4 inch loss at shortest side)

. If I choose option 1) this gives me an asymetrical perspective from my listening position if facing down long side. The alternative isto sit facing a long wall which I have understood is not the best option acoustically.

I have many questions but one main one at this stage.

Is option 2) my very best one or are there other factors to consider?

any thoughts much appreciated.

[Soundman2020]

timber frame (floor area 4x5m)
OSB with 18 mm shiplap cladding
4x2in wooden studs
50mm RW3
2 layers of 15mm acoustic plasterboard.

Isolation will be about 35 dB. Is that good enough for what you need?

roof height-2.5m (maximum allowed subject to UK permitted development rules)

The roof can actually be higher than that. 2.5m is the maximum height at the eaves, but the roof can go up to 3.5m.

Is option 2) my very best one or are there other factors to consider?

Yes, option 2 is your best bet. That's the right way to do it. Have the ceiling lower over the speakers, and higher towards the back of the room.


- Stuart -

[tomugli]

2.5 is the maximum permitted height of a building to be exempt from planning permission in the U.K. (Considered permitted development) when building within 2 meters of a boundary.

[Soundman2020]

To clear up the confusion, here is what the regulation actually says, regarding class E additions to a property ("Permitted Development"):

Under Class E, the following limits and conditions apply:

E.1 Development is not permitted by Class E if

...

(e) the height of the building, enclosure or container would exceed
(i) 4 metres in the case of a building with a dual-pitched roof,
(ii) 2.5 metres in the case of a building, enclosure or container within 2 metres of the boundary of the curtilage of the dwellinghouse, or
(iii) 3 metres in any other case

The height of the building, enclosure or container should be measured from the highest ground level immediately adjacent to the building, enclosure, or container to its highest point.

If any part of the building, container or enclosure is within two metres of the boundary of the curtilage
of the house, then the height limit for the whole development is restricted to 2.5 metres if it is to be permitted development.

(f) the height of the eaves of the building would exceed 2.5 metres

The eaves of a building will be the point where the lowest point of a roof slope, or a flat roof, meets the outside wall of the building. ...

Under Class E the maximum height of the eaves on any part of the building (irrespective of total height) is 2.5 metres. For example, on a building with a single - pitched roof, the 2.5 metres eaves limit and three metres maximum height limit would be as shown below...

You can find the full Permitted development document here: https://www.gov.uk/government/uploads/s ... idance.pdf

- Stuart -

[tomugli]

Absolutely Soundman.

in your case Pepeluis stick to 2.5 m as you're only 1m from boundary.

Planning portal is a very helpful site, and contains some really helpful, easy to access info on these issues.

[Pepeluis]

thanks tomugli and Stuart for your responses, I did check the planning poeral and called the local planning department before building, as I was 60cm from boundaries I made sure no part of the building was higher than 2.5m to comply with the regs.
appreciate your help, thanks
Jose