Structural calculations

[mOskit]

Hi All
Newbie here.
I would like to convert my loft to a usable space. I`m not interested in dormer just what is seen on the pic. I want to remove the roof support and brace the floor to make it my new bedroom.
I`m in need of a structural engineer I believe that will tell me where to and what type support i need in order to create open space.

Can someone point me in the right direction please? Trying for few months now but i only see Architects wanted to sketch stuff where i`m not changing anything on the outside and i would like to do everything under permitted development due to my own workforce.

I`m in Reading Berkshire

Thank you
Kris

 

[^woody^]

An SE will design beams to take loads, but he won't tell you what loads, what type, nor where to put them, as that's part of the designers job. Otherwise you need to instruct an engineer to design the conversion too.

 

[Notch7]

It doesnt look big enough to me....but could be just the pic

loft conversions need a fair bit of insulation etc to be compliant, head room soon disappears.

 

[mOskit]

Thanks guys for the info. 2.20m is the highest point in here. I cannot afford to go bigger or put the dormer. also according to the regs you cannot go higher than existing height of the roof.? Do you guys know any SE in berkshire that I could get in touch to talk about the details? Thanks

 

[garyo]

I'd ask a loft conversion company around for an opinion. They'll eye up the floor structure and establish whether you're probably going to lose another 100mm beefing up the floor joists, and be able to talk about stair locations, head height, and general feasibility.

i would like to do everything under permitted development due to my own workforce.

Not sure what you mean by this?

 

[^woody^]

As a guide, the new floor will tend to reduce the headroom by at least 170mm and the new rafters and or insulation by at least 150mm - and that's in optional conditions.

You don't just want any old engineer either, as they need to be able to design lofts and know the other regulations - many engineers just know structural stuff, not design. Be explicit with any instruction and ask if they can do all that you require.

 

[tony1851]

From my experience, you don't need to sacrifice 150 in the roof for insulation. A lot of private inspectors will accept a lesser standard if it compromises headroom (which it would here). I've often just put 50 between the rafters and 25-50 below + plasterboard without issues.
Admittedly LABC bods will usually hold you to far greater thickness.
For the floor,you try to sink the new joists as low as you can between the existing ceiling joists, but much depends on spans and potential support points.

 

[^woody^]

I've often just put 50 between the rafters and 25-50 below + plasterboard without issues.

Why bother following any regulations at all then? Just do what's convenient, what's cheap, get some Joe to sign it off and all's well. A bit like Grenfell.

 

[tony1851]

You know that any thickness of nsulation in a conversion must be 'reasonable'.

 

[^woody^]

Ah-hah!