Victorian mid terrace property and loft construction

[Builder2011]

Good evening. My loft has been packed for years with heavy boxes on miscellaneous boards across the joists. I have now got a moment to strengthen the joists and put down some proper boards. The building is about 7m from front to back and about 4.6m across and is a Victorian mid terrace building on ground and first floor.

The existing loft joists are 3.6m from front to middle resting on a 4" x4" across joist from party wall to party wall, and then 4.2m from the middle to the rear. They are 4" x 2".

The across joist from party wall to party wall is a 4" x 4". It has two 1 1/4" inch round holes cut in towards the middle for wires. Through the holes I see that the wall below (first floor middle across wall) is not a solid wall (or that part of the wall that I can see).

So if the wall below is not load bearing, how is the 4" x 4" across joist holding up all the loft joists? And can a 4" x 4" joist from Victorian construction really span 4.6m, and if so how has it held up so many heavy boxes for so many years?

The middle across wall has one door way. On the upright side of the door nearest the middle of the building the wall does seem to be solid for about 4". Could there be a support there? Are there any drawings available for this type of Victorian construction?

 

[ajrobb]

The across joist from party wall to party wall is a 4" x 4". It has two 1 1/4" inch round holes cut in towards the middle for wires. Through the holes I see that the wall below (first floor middle across wall) is not a solid wall (or that part of the wall that I can see).

So if the wall below is not load bearing, how is the 4" x 4" across joist holding up all the loft joists? And can a 4" x 4" joist from Victorian construction really span 4.6m, and if so how has it held up so many heavy boxes for so many years?

A load bearing wall doesn't have to be solid, it can be timber frame. Maybe you have 4x4 pillars rather than studs.

Have a look at //www.diynot.com/forums/viewtopic.php?p=1704487#1704487

Untitled

• teracir
• 14 Aug 2010
• 2

 

[Builder2011]

Yes thanks. Having inspected between the walls with an inspection camera, the wall is as per the photograph. The 4"x4" pillars are at 380mm centres.

Is there anywhere where the load bearing capacity of this type of wall can be confirmed? Has anyone added pillars to this type of wall to allow for any additional loading instead of removing it all to make way for an RSJ?

 

[Static]

Check if it has a foundation

 

[ajrobb]

Is there anywhere where the load bearing capacity of this type of wall can be confirmed? Has anyone added pillars to this type of wall to allow for any additional loading instead of removing it all to make way for an RSJ?

It sounds like your plans are well on the way towards a loft conversion. You'll need an SE to assess not only the strength of the middle wall but also the front and back walls (e.g. wooden lintels).

The people you need to keep happy are your local Building Control. You can go and see them for free.

If you are thinking of an RSJ between party walls, you should be aware of the Party Wall etc. Act 1996.