Architect or Structural Engineer

leinster93

Here's hoping someone can give me a bit of direction with whether I need an architect or a structural engineer.


I've been looking at converting the attic of our two story. Measurements are length - 10m, width - 6m and height - 2m.



First off, I don't see any benefit in looking for planning for dormers due to the existing height being less than 2m. Besides this, I have a row of neighbours which I would be overlooking to one side and I've no doubt at least one would object to any planning application. What I would be considering is velux windows to the rear which as I understand does not require planning.


My lack of understanding though is whether I need to get an Architect or a Structural Engineer given that the length and width of the house with stud walls in the upstairs. So how exactly an attic conversion can be achieved with RSJ's I am not sure how it can be done or if it will be economically viable.



Where funds are tight I am not sure if we need to get an Architect or a Structural Engineer. Would anyone have any guidance?


L

Wildly Boaring

Architect.
They will need an engineer's input on one item. The loading for RSJ and associated bearing.

leinster93

Sorry, are you saying I need both or that the Architect will refer to a structural Engineer?

Wildly Boaring

leinster93 wrote: »

Sorry, are you saying I need both or that the Architect will refer to a structural Engineer?

You employ the architect he/she will probably have to have an engineer do the calcs on the rsj and it's bearings.
(And any other structurally significant elements)

My view as engineer. Perhaps there are arcitects who can do the calcs and happy to stand over them

Gumbo

My opinion is you don’t need an architect here.
You have a triangle space in the attic. You cannot design anything different.

You basically need to create access, new structural floor and associated structural elements to support this floor and roof rafters.

I’d go straight to the engineer to design how the existing structure can be altered to create the space required.

You will of course have insulation and air tightness details to hammer out.

leinster93

Okay, so given the span is 10.1m x 6.1m, will an engineer provide details and drawings of the location of rsj's, type of rsj's to be used for which an attic conversion company to work off?

Gumbo

leinster93 wrote: »

Okay, so given the span is 10.1m x 6.1m, will an engineer provide details and drawings of the location of rsj's, type of rsj's to be used for which an attic conversion company to work off?

That’s what you’ll be engaging them For and paying them for. An architect cannot do this.

Wildly Boaring

leinster93 wrote: »

Okay, so given the span is 10.1m x 6.1m, will an engineer provide details and drawings of the location of rsj's, type of rsj's to be used for which an attic conversion company to work off?

Fair enough
And maybe the answers to these sort of questions are straight forward a lot of engineers will steer well clear....
Fire?
Access size? Stairs?
No planning for velux?
No planning at all?
Insulation?

I mean I know a lot of the answers just wouldn't put my name to them on a set of drawings.

Gumbo

Wildly Boaring wrote: »

Fair enough
And maybe the answers to these sort of questions are straight forward a lot of engineers will steer well clear....
Fire?
Access size? Stairs?
No planning for velux?
No planning at all?
Insulation?

I mean I know a lot of the answers just wouldn't put my name to them on a set of drawings.

Fire : straight forward Part B compliance. If 2 storey into 3 storey then more strict than single storey into 2 storey. DoE loft conversion leaflet can aid here also.

Access size : cannot be altered. It’s an attic and the space is dictated by the existing roof envelope.

Stairs : Part K gives a section for stairs into loft conversions. Not as strict as primary stairs.

Velux to rear : no planning required.

Insulation : I recommend the metac system and isover system from saint Gobain.

I know plenty of engineers that over see these works every day.

leinster93

Looked at the Building regs for stairs access, head height, non habitable height compliance etc. The stairs is the tricky bit in trying to avoid taking a chunk out of a room.

Thanks for the help.

Gumbo

leinster93 wrote: »

Looked at the Building regs for stairs access, head height, non habitable height compliance etc. The stairs is the tricky bit in trying to avoid taking a chunk out of a room.

Thanks for the help.

I assumed from the outset you would be non habitable as the height of 2m will rule this out.

leinster93

kceire wrote: »

I assumed from the outset you would be non habitable as the height of 2m will rule this out.

To keep with the existing stairs would require taking 400mm off an existing room based on compliance from the regs. Where the attic conversion is under 2m is it worth it is the question i need to answer for myself.
It is a lot of storage space in the attic/ play room for the kids...

Calahonda52

leinster93 wrote: »

Okay, so given the span is 10.1m x 6.1m, will an engineer provide details and drawings of the location of rsj's, type of rsj's to be used for which an attic conversion company to work off?

As i said before the engineer will need to sign off on this as the work progresses:
its not just enough to say use
a 1,016 by 305 by 457 (or smaller ) and walk away and let it all get covered up: do you understand the difference between the two approaches form a paperwork perspective?