Loft joists advice

[rjsnipe]

Hi,

I would like to raise the level of my joists so that I can lay flooring and retain the extra insulation. It is just for storage.

I have read about loft stilts and they seem like an overly expensive option.

I have read as many posts as i can find on raising the level of the existing rafters but need some advice on my specific situation.

Some people advise laying new joists perpendicular to the existing joists and a few have suggested it is better to lay them on top of the exiting ones but with a few braces to add lateral strength.

What all the advice has in common is to consider where the load if being placed. ideally it should run between load bearing walls. Similarly it also seems that for light storage it doesn't really matter if the load is just on the existing rafters as it will all be spread out anyway. I know there was a water tank up there before and if it could take that then there is nothing i will store up there that will come close in one location

The issue I have is its not clear to me where the current joists are getting their structural support on one side of the house. The house is 1930's and it is an end terrace of 4. On the party wall you can see the joists are embedded into the wall. On the other side the angle of the eaves makes it look like they must only be nailed into the rafters. If i was to lay the new joists on top of the existing ones then the best i could do it bolt them into the rafters on one side and I am not sure what I would do on the other side with the ones going into the wall as there would be nothing to fix onto.

Here are some pictures, first few are just to give a sense of the place. I move the camera round to my left

Then some of the eaves

And finally the party wall side this is one of two large beams, not sure what they are called

and this just shows how the joists when getting to the chimney go around it.

The joist either side of the chimney are embedded in the wall as mentioned before, but the ones that are in the middle, the ones closest to the loft hatch just go up to this cross section shown, and on the other side it looks like they are just nailed into the rafters. I can't see any sections of wall where its resting if it is, all the insulation i have pulled up you can see the ceiling, lots of thin strips of wood with plaster coming up through

Any advise appreciated

 

[rjsnipe]

Here is the rough floor plan

Left is ground floor, middle first, right roof. The are not 100% accurate but close.

Left side is party wall, right side is the one where the angle of the eaves cut across the first floor ceiling and thats the part I have the issue with.

Here is an image from the landing looking at the eaves that cross that side of the house. So the joist don't make it all the way to that wall.