Floor requirements for building regulations

[Forkhandles]

Hi,
I am soon to start work on converting my basement in to dwelling rooms. fortunately it does not suffer from damp as basement only covers the rear portion of the house and has a door that opens on to the garden. However the landing area at the bottom of the stairs has a height 1.8 to meters the bottom of the ground floor joist so to meet building regulations I need to excavate the existing floor to bring it to the minimum 2 meter height requirements.

My question is what are the minimum requirements for hardcore (MOT1), sand, DPM, Concrete, Insulation, screed etc that meet current building requlations for a domestic dwelling. I tried various online searches to no avail and as this part of the forum has over 140 pages I am slowly begining to loose the will to live.

I am not looking for what you would recomend but the exact minimum specification as the current floor area of the basement is over 32 m2. The thought of digging out about 20 odd m3 by hand is not the most appealing.

Also I am not just gong to dig up the landing area and then have a step up in to the room.

 

[^woody^]

There is actually no minimum requirement for hardcore, sand or concrete to meet building regs. So you may have to ask for recommendations instead

The minimum spec would possibly be ... roll the ground flat, lay some polyphene, lay some insulation to meet 0.22 w/m2k, anf then drop some chipboard on top. That will satisfy Part C, A and L1a

I know I've posted a typical concrete floor spec a few times in the past couple of months.

 

[Forkhandles]

Ok, So it looks like I will now have to ask for your recomendations for a concrete floor spec.

I curently have to excavate down 220mm just to reach the minimum celing height for the landing area. As the total floor area is 32m2 reasonable recomendations are welcome. The floor will only be an internal domestic floor with no requirments to park a tank on it.

 

[noseall]

100mm compacted mot.

25-50mm sand blinding.

1200 guage dpm. (edited)

125mm polystyrene 'jablite' insulation with 25mm external perimeter upstand.

another layer of polythene.

100mm concrete slab. (trowelled if omitting the screed)

75mm screed. (optional)

 

[Shytalkz]

Why type 1 or 2? It's a basement, the ground is pobably well compacted as it is, so give it a light wack and construct off that. Saves having to overdig only to import sub base material as well.