Broken and bolted purlin, dip in roof, what to do

[compact]

The photos below show the purlin in my attic, which looks like it has snapped a long time ago, snapping or splitting most of the rafters on that side, but has been repaired and doesn't look like it has moved in many many years.

The Purlin has been bolted together and looks pretty secure (Why then never square cut the ends I don't know.
The rafters have been spliced and bolted where ever there is a split or crack.

The small triangle or bricks definitely look dodgy, but they also look like they've been sitting there for many, many years.
I've taken a few bricks out of the bottom to fit in the steel for joists (turning the attic into an extra guest/child bedroom) and am going to replace them.

There is a small dip in the roof from the outside, I'm not worried about it falling down, however I do want to repoint/rebuild supporting triangle of bricks

So what do you think to this?
1) Lay wood across the new joists, build up with wood, then using a jack take weight off the triangle of bricks and rebuild it

2) I'd like to use the jack to take some sag out of the roof. Is this possible?
Can i cut/grind the original bolts, knock them through, raise up the roof (and inch or so) drill and new bolts?
I'm concerned about upsetting the tiles.
Also as the roof as been settled in the sag for so long, will it pop back into it's original flat (no dip) state?

3) Finally I'm looking to add extra wood against any of the rafters that has spilt and repaired, as a just in case.

Thanks for replies in advance. My thoughts are it's been like this for decades, so what ever I do I don't want to mess things up, but then I don't want to go to the whole cost of stripping the tiles off.

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• compact
• 20 Oct 2014
• 1

Untitled

• compact
• 20 Oct 2014
• 1

Untitled

• compact
• 20 Oct 2014
• 1

Untitled

• compact
• 20 Oct 2014
• 1

 

[Infoelec]

Your best bet would be to secure the beam using metal plates either to strength it, or replace it entirely.

Jacking up will be difficult as it is a heavy load, however you could achieve this if you use steel plates on each side, or remove the beam and use a steel.

 

[Brigadier]

I had the same, and agree with Infoelec. Heavy steel plates either side, plentiful fixings, and leave it.
(When we bought the house, the surveyor commented on the dip in the roof and cracked purlin, but also observed that there were no signs of movement).

Everything moves, rots, degrades, etc, and everything will end up falling down eventually (without ongoing watchfulness and perhaps maintenance or replacement); it is just a case of the rate or speed of the "decay". If measured in years or decades, probably not to worry above ongoing scheduled work.

 

[ree]

compact,

are you still there?
there are a number of things ref your roof that you should know.

 

[tony1851]

there are a number of things ref your roof that you should know.

Which are......?

 

[compact]

Hi thanks for the replies, apologies for late reply myself.
After looking at the neighbours, the brick support is standard building practice round here, for this type of house.
They use a double purlin at the front for the whole width as there are no supporting walls up to the attic (brick on grd, cinder on 2nd).
For the rear, there is a brick wall between the small kitchen and rear room (that most people take out) and the same runs up between bathroom and bedroom.
My plan is to prop either side of the triangle and re build it.
Then put a joist in behind running from gable wall to the triangle (basically replacing the small broken purlin for strength)

I'll leave in the small broken purlin, as it's doing no harm.