Rooflight Loft Conversion, floor support ?

[NavSG]

Right im gonna be putting in a Full Plans Application for Building Regulations for a velux loft conversion (no rear dormer), so i wont need planning permission but work needs to comply with the Building Regs. In terms of supporting the floor i know the convention is to insert steels across the party walls supported on concrete padstones and floor joists to run from one steel to the other. But i was thinking i have a spine wall all the way down to the ground floor (no through lounge). Would it be possible to span floor joists parallel to the party walls, from the front wall to spine wall and from the back wall to the spine wall thus eliminating the need for steels and structual calculations ?

TIA

:confused:

[caj]

I would advise you check with your local building control office, most surveyors will be happy to visit and advise if structural calculations, and indeed steelwork, are required for this work. If you don't know the contact enter your postcode on the following website.

http://www.labc.uk.com/site/index.php

[jeffrey]

Right im gonna be putting in a Full Plans Application for Building Regulations for a velux loft conversion (no rear dormer), so i wont need planning permission but work needs to comply with the Building Regs. In terms of supporting the floor i know the convention is to insert steels across the party walls supported on concrete padstones and floor joists to run from one steel to the other. But i was thinking i have a spine wall all the way down to the ground floor (no through lounge). Would it be possible to span floor joists parallel to the party walls, from the front wall to spine wall and from the back wall to the spine wall thus eliminating the need for steels and structual calculations ?

TIA

:confused:

You may also need neighbour's consent and/or Party Wall Act Notices. Consult a specialist surveyor re this.

[NavSG]

You may also need neighbour's consent and/or Party Wall Act Notices. Consult a specialist surveyor re this.

Yeah both neighbours are cool, is it 2 months notice i have to give them ?



I was told by a BCO friend that the floor joists can in principal load directly on to the existing spine wall but i will need to justify the wall's adequacy.

I will need to excavate a trial hole to expose the wall's foundation. Once the walls foundation is exposed to call a Building Control Officer out to inspect. The result of the inspection will depend on depth and width of foundation and the subsoil it is sitting on.

In general he said that a foundation with a depth of at least 400mm (Floor level to bottom of concrete), and a projection of 150mm (Wall to edge of concrete), sitting on virgin (unmade) ground would be acceptable.

I've just completed my BSc Building Surveying so will be drafting the drawings myself on AutoCAD. If i can do without steels it would be great, even with steels i know some structual engineers who said they'll do the calcs and beam design for £120.