loft conversion questions

[Jsmithy]

Hi everyone this is the first time i am asking a question on this site but have been reading for months
unfortunatly this is the second time of writing this question as i did a spell check and had to allow popups and lost all my text
So here i go again lol.
The question i have is:
I would like to do a loft conversion but the height of the ridge to the top of the ceiling joists is approx 6'5" and i would like to know if it would be alright to hang the new floor joists on hangers from wall plate to wall plate.
This would be at the same level as the top of the existing ceiling joists so i could keep the height in the loft.
The span between the wall plates is 18' and there is a stud wall inbetween at 9' which seperates two bedrooms (front and rear) i realise this wall isnt load bearing but could i make this load bearing so the floor joists could be smaller?.
I know this would mean lowering the ceiling height in the bedrooms but the height now is 8' so a loss of 6 to 8" would not be a problem.
Thanks for your help on this and i hope the questions make sense
Jsmith

 

[noseall]

I get where you are coming from. The chances of you being able to split the span of the loft joists by using a first floor stud wall are slim. Granted, if this were possible then they could be as small a section as maybe 125mm x 50mm.

Whatever the joist size, any increase in joist depth, to those that already exist, will decrease the wall-ceiling height so long as you are sitting them upon the existing wall plate.


Using hangers will create a lot of disruption to the exiting ceilings and subsequent electrics/lighting etc.

 

[Jsmithy]

Thanks noseall,
I realise that using joist hangers will cause me to redo the ceilings to the bedrooms but if this means i can have a usable space in the loft room then i am willing to have the disruption,
so long as the cost wouldnt outweight the gain,
do you know if there would be an issue with putting in a concealed beam under the stud wall to help support the loft floor??,
or if there would be an issue with placing any extra load on the wall plates as they are already taking the weight of the roof?.......thanks for your time.
jsmithy

 

[^woody^]

You will also lose about 3" under the rafters for insulation - even more if the rafters need up grading and purlins removed.

Even at 6' in the centre, this gives very little usable space unless for hobbits, as the ceiling line diminishes outwards into the room

 

[Jsmithy]

You will also lose about 3" under the rafters for insulation - even more if the rafters need up grading and purlins removed.

Even at 6' in the centre, this gives very little usable space unless for hobbits, as the ceiling line diminishes outwards into the room

lol No hobbits,
I would be putting a dorma on the rear which would be the length from the party wall to the slope at the hipped side(Allowing for regulations on distance etc) or does this idea sound like flogging a dead horse
surley there is a way

 

[^woody^]

Even a flat dormer roof is going to be minimum of 170mm thick (probably more like 240 thick though), so think about how this is going to work externally and internally

 

[Jsmithy]

I see your point,
ive been thinking of ways to get this to some kind of so;ution to this but keep on stumbling!
This is where this forum comes in to the equation
The exixting ridge is 6" by 2" and if the floor was at the height of the existing then with the insulation in the roof and plaster board would this allow for a minimum of 6 foot head room?,
also does the existing roof have to be of thicker timber at the sloping side(opposite the proposed dorma)
thanks for any ideas.

jsmithy

 

[^woody^]

By the sound of it your loft is not suitable for conversion.

Your 6'5 to the ridge, in context, is less than a standard door frame height. Deduct the allowance for insulation to the rafter underside and remember that the ceiling gets lower out from the ridge, and you wont even be able to stand upright in the loft, and will bang your head as soon as you step from under the ridge line. A dormer will not help either

You will have no usable room, and you may not even be able to get the minimum heights for the stairs

A 35 degree pitch and a roof span of 9m is often the minimum requirements for a feasible conversion

And even if you drop the ceiling to get the new floor in, you will end up with a cramped 1st floor and a cramped loft, and a seriously devalued property

 

[Jsmithy]

tried to put pic up but havnt got time at the mo
put a pic in my album but not sure how to let people view it?[/img][/list]

 

[Alastairreid]

View media item 15827

 

[^woody^]

That looks to scale - the loft ridge height is higher than the other two floors!

You need to draw it accurately or its meaningless.

You will also have a job getting a dormer of that design past planning. Its not a dormer its a 2nd storey extension

 

[Jsmithy]

Thanks for putting the pic up alastairreid
Woody that pic isnt my own work, i should have said what do you think of this idea?,
I would have to get a to scale plan up and get opinions but in principal with the measurements i have quoted in previous posts would the idea in the example plan be practical?
Thanks for help/opinions

 

[Jsmithy]

Also my loft would be to restrictions for a dorma to permitted distance from the eaves and not like the plan which comes of the house walls.

 

[Jsmithy]

Untitled

• Jsmithy
• 20 Oct 2009
• 1

does this help Woody?
figured out how to put pic up

 

[^woody^]

It does not seem to help your situation

What angle is the roof, and how wide is the house internally from front to back?

And is your 6'6" to the top or bottom of the ridgeboard?

Are the rafters and ceiling joists 3" deep?

Let me know and I'll do a scale section, and all will become clear