loft flooring question

Hi I'm flooring part of my loft with tongue and groove chipboard sheet 2400x600. The house is about 6 years old with concrete block wall and wooden ceiling joists.
There is a place where a conc wall protrudes above the level of the ceiling of the joists. It runs in line with the joists and the bottom of the blocks is just above the ceiling/plasterboard level, so it doesn't seem to serve any purpose.
There is also a place where a short steel beam bridges a corridor underneath. There is a row of conc blocks mortared on top of it which are already loose and seem to serve no purpose either.
Can I just remove them, so I can run the flooring right across the top or are they important for some reason?
(I noticed a place where a few have been removed for an expansion tank platform )
Thanks for any advice.
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Oh, sorry, forgot to mention house is in UK so maybe I'm asking in the wrong place for this kind of construction?
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This groups is rather USA orientated.
Try...
http://www.ebuild.co.uk/cgi-bin/forums/discus.pl
Register on the forum, drill down far enough and you will see a "start new thread" link appear at the bottom of the page.
It does sound like these blocks are redundant but sometimes there is a reason. For example certain types of joist hangers need a minimium height of wall above where they are inserted.
Is this new floor just for storage or are you converting the loft to a play room etc? If it's being converted then take care. If the loft insulation is at loft floor level you may have a problem with condensation. It's common for the loft floor to act as a vapour barrier. This prevents warm humid air from the house getting into the cold loft causing condensation on the rafters and then rot. Leaving the loft hatch open or opening it regularly is not a good idea. In addition to the vapour barrier lofts also need cross ventilation to remove any water vapour that does get in - so this type of loft will be cold in winter. If not then the ventilation might be inadequate. These vents are (should be) in the eaves and are frequently blocked when people board or add extra insulation to the loft.
If the loft is insulated at rafter level (or you plan to do so) then the correct proceedure is to allow a 50mm ventilation space between roof felt and insulation. Install vent tiles at the ridge so air can go in at the eaves, up this 50mm gap and out the ridge vents. A vapour barrier is added below the insulation before plasterboarding. Confusingly this type of construction is called a "cold roof" but the loft itself is made warm.
Technically if converting the loft for other than storage you need Building Control Approval and that might be a lot of work. For example it can involve upgrading the fire resistance of doors on the ground floor to comply with the regs for a three story house (self closing doors a no longer required though).
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The concrete block might be part of a demising partition/wall (aka a party wall) that is there to prevent the spread of fire between adjacent units. Your local code might require the block to extend to a certain height above the ceiling.
Your local code and local building official will have the definitive answer.
R
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Thanks for help. I'm just flooring about 1/4 of the total loft space for some extra storage. It's not tall enough for a conversion. I'll find out more about the fire aspect. Al
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