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joist size

Postby sam.melton » Tue Nov 25, 2008 12:51 pm

Hi im Thinking of adding A room in my loft, but need to replace the joists. My house was built in 1901, and is 6.42 meters long by 4.9 meters wide, the head hight that i have is 1.89meters. I no that the head hight is a problem, so im thinking of lowing the floor in the loft, but i need to no how to best do this and what size the joists will need to be. On the top floor there is no surporting walls, so the joists will need to be able to take the span. The joists at the moment dont seam to be load bearing (for the foof), they rest on top of the wall and with only one nail in to the rafters. There is tho two full lengths of 3x9 running the with of the house (resting on the end walls), with brackets holding up the joists. Do i use these to surport my new floor, in the same way?
Or can i get a way with fitting battens to the two end walls, lower then the current joists are and hang the new joists off these with brackets?
I hope that i make sence, and that some one can help.
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Gorilla Glue heavy duty grab adhesive

Postby Tony Newbold » Thu Dec 18, 2008 8:19 am

What you are contemplating sounds very risky. You need to discuss with a qualified builder if you are planning to move modify existing joists, they are probably holding up your roof in an "A" frame design and should not be played about with. :
Hope this helps
Tony Newbold
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